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Engines => From Kits/Castings => Topic started by: Alyn Foundry on September 12, 2017, 05:08:04 PM

Title: A Robinson from rejects.
Post by: Alyn Foundry on September 12, 2017, 05:08:04 PM
As time went by I amassed quite a few " rejected " castings probably due to the fact that both Rhuddlan and Buckley foundries " final assessment " areas were pretty dimly lit!!

Before I sent a kit on its way all castings were thoroughly checked for the usual imperfections that the model engineer would also be looking for.

With the recent upheaval and dispersement of Vincent's workshop I managed to find a near complete set of castings for the half scale Robinson " X " type or " Chippie " engine.

Over the next few months, as time permits I will present a build log of a Robinson from rejects.

The flywheel has always been my favourite item to machine first..... More to come.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Jo on September 12, 2017, 05:09:24 PM
 :( That one was on my build list but I could never find any castings  :'(

Jo
Title: Re: A Robinson from rejects.
Post by: Jasonb on September 12, 2017, 05:42:32 PM
I like that one too and had been looking at how the cylinder could be fabricated or more likely machined from a lump of iron, main bed casting is not too bad to do as it is quite boxy.

Look forward to following along with your build.

Out of interest what sort of numbers were sold?

J
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on September 12, 2017, 05:59:54 PM
Hello Both.

Well....

I have nearly 15 rejected cylinder castings due to metal " shrink " within the inlet/exhaust tract area. This was eliminated by using an internal " Nob " , foundry parlance for an internal mass of Iron close to, on the runner where the shrink would occur. Because this mass was deep in the sand it kept its heat, feeding the casting as it cooled.

I basically kept a whole batch of possibly suspect castings rather than send them out.

The rather pretty number plates were photo etched by a firm down South, I bought 200 of them and the box is almost empty, 180 or so??

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Nick_G on September 12, 2017, 07:12:14 PM
.
That is a really interesting engine.  :ThumbsUp:

I do however confess I had to google to find out what exactly they were.!

To save others who are also not aware here is a video (of a full size one)

http://www.youtube.com/watch?v=kXyPqcM_yPI

Nick
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on September 12, 2017, 08:39:31 PM
Hello Nick.

Many thanks for the video link, I was working from my ancient tablet earlier.

The video shows a later patent engine with the conventional 2:1 in line gear reduction running on hot tube ignition. My replica was based upon the 1894 patent epicyclic gearbox version.

Here's a link to number 103, the first model built by me.

THLPKtyxVdc
My website is still open at.... http://www.alynfoundry.co.uk/  Lots of nice photos to look at.   :)

Oh these engines are from the same manufacturer as the hot air engines. Mr Horace Robinson was a very clever man IMHO.

Cheers Graham.

In case anyone was wondering where the " Chippie " term originates?   English slang for a Fish and Chip shop. Picture shows engine and potato chipper.   ;)
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on September 13, 2017, 03:20:59 PM
The Robinson was my first attempt at " true " scale modelling, an iconic design in my opinion.

Known as the " oblique " range they were made in various sizes up to, according to literature 10 HP !! The base doubling as a water tank. I haven't seen a larger one than the type " Z " circa 3 HP.

As with all early British Gas engines the Robinson has a rather chunky flywheel weighing 80+ Pounds at full scale with a diameter of 17 inches. They began production around 1890 with an engine that used the
" ratchet " wheel to get around Otto's four cycle patent stranglehold. My version dates from 1894 or thereabouts.

All foundries have their " ways " of doing things, Rhuddlan used to like pouring directly into the hub and have a large funnel shaped " sprue " to feed the casting with the hottest metal. Buckley on the other hand preferred the " Nob " on runner system, feeding the metal towards the hub via a couple of the spokes.
The casting I chose to machine was a Rhuddlan one with a whacking great shrink into the hub, definitely one not to be sent to a customer!

My workshop companion of over 30 years is a Le Blonde RP of wartime era. She's big and powerful but with a feel so good that even small precise parts can be made on the same machine. No leadscrew no topslide just power feed to " X " and " Y " with reverse facility and a monster four way toolpost. I got so used to her that I could put a single thou on with a rock of the handwheel.

For flywheels my preferred method is to use my 8" diameter " monoblock " 3 jaw chuck and grip the inner rim by expanding the jaws. You can now see visually any " runout " and correct it by packing. The inner rim is un machinable, best to get that running true isn't it? I first tackle the hub and face off the front followed by a centre spot to carry a rotating centre, belt and braces!!

With this method all faces of the wheel will end up being concentric to the bore, not a wobble, ever!

Once faced I move onto the bore, in this case 1/2" diameter. As previously mentioned this wheel had quite a shrink cavity so I opted to use an over centre cutter rather than a drill bit to reduce any " whip " or wobble. It turned out to be only shallow so I re spotted and finished with a twist drill.

I hate to see wobbly flywheels the usual cause is a poorly machined hole. I always drill undersize and use a tiny boring bar to get to the required size. Tedious, yes but well worth the extra effort. Drill bits can start to wobble and a reamer just follows. By boring all wobble is eliminated and the use of a floating reamer to take out the last few thou makes for a perfect ending.

The final stage is to remove the wheel from the chuck fit your reverse jaws and machine the back face and hub. The chuck jaws providing the datum.

A well earned " cuppa " completes this exercise. Pictures to follow.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Ye-Ole Steam Dude on September 13, 2017, 03:36:50 PM

I like the unique design of the Robinson.

Thomas
Title: Re: A Robinson from rejects.
Post by: Jasonb on September 13, 2017, 04:33:09 PM
Thanks for enlightenment on the "Chippie" name, I did not know that was how the engine got its name. I assume Robinson's also made the chipper and stand as it all looks to be made to suit. That would be a busy chip shop to need a 10HP engine!

I also prefer to use a boring bar on flywheels, infact any hole that matters. With a casting there is even more risk of the drill wandering due to a bubble or hard spot and as you say a reamer will just follow the drills path.

J
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on September 14, 2017, 04:02:34 PM
Hello Jason.

It seems AE&H Robinson manufactured a range of catering equipment the engines providing the power.

I had a copy of a booklet listing the sizes of engines they made, the 10 HP engine stood at a height of 4 feet!!

Regarding the flywheel, are pictures necessary? I mean it's the same old,same old. You could do them on a faceplate too, the trick is to get some packing behind to allow the cutting tool to finish right off the top face.

The keyway on the half scale engine is 1/8" with a 1:100 taper Gib head key securing wheel to shaft. I have a few left over keys from my building days.  ;)

I have for many years used push broaches for bore keyways, no they're not cheap but they do a great job quickly. Two to three passes is all that's needed. The only downside is the bushes supplied are far too short
I had to make my own. Dead easy under a fly press or arbour press. I used my medium fly press to finish the job. The flywheel now just needs cosmetic attention before painting.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on September 17, 2017, 02:09:33 PM
Perhaps the most interesting part of the engine is H Robinson's 1894 Epicyclic reduction gearbox.

I made inquiries to various gear manufacturers about this rather special internal gear with its eccentric outside diameter to be met with almost telephone number prices! Something had to be done as I couldn't see prospective customers paying a " Kings ransom " for such a small part.

Remembering that some UK agricultural engine makers had used " cast " gears rather than machine cut ones led me to thinking along the lines of gravity " Die castings " using a Zinc alloy. I chose a large tooth form to help with the non standard mesh that would occur by using an external gear as a die to form the internal casting. The final result actually beat all of my expectations, I was very pleased indeed.

The attached photo shows the 3 piece die, a casting and a gearbox I made a few years ago. Alongside is a gear I cast and machined yesterday.

I shall go into more detail on the making of this small but vital part next.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Jasonb on September 17, 2017, 07:13:11 PM
You had better get your finger out if you are going to use up all those keys :LittleDevil: Do you cut your keyway in the flywheel to a matching taper? I have made a few bushes with the taper and as you say longer ones are often needed to support the broach through a long hub. I did buy a set of far eastern broaches - 1/16, 3/32 and 1/8 with bushes for a reasonable amount which are OK for the smaller models but 5/32 and 3/16 are also needed.

I had thought of doing the internal gear in much the same way as I did keyways before I had the broaches by using a profile tool in a bar held in the toolpost and plane out the teeth with the carrage, I did have a quick try and it looks like it should work.

(http://www.model-engineer.co.uk/sites/7/images/member_albums/44290/434999.jpg)

I suppose now an option would be to laser or water jet cut the part, either offset in a disc that could be soldered into the arm or with the whole are that could then be further machined and then dressed to look like a casting. Look forward to the detailed description.

J

PS I think we have all seen flywheels being machined so can let you off that one ;)
Title: Re: A Robinson from rejects.
Post by: Chipmaster on September 17, 2017, 07:40:50 PM
Hi Graham,
This will be an interesting build and I'm looking forward to seeing how you tackle rejected castings which we talked about recently. I've had my fill of reject wheel castings lately!

Regards
Andy
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on September 17, 2017, 08:57:29 PM
Hello Jason.

Well.... This might not be the " correct " way to use the Broach, but as they are made with a 1:100 taper I stop pushing the Broach on the last pass before pulling it out. This leaves me with the required taper in the flywheel boss. The correct way, of course is the taper in the bushing approach.

I like the indexed idea shown in the photo but you will have to secure an eccentric outer shell to drive the outer strap back and forth.

Hello Andy.

Thanks for looking in.

The castings I rejected were mostly of a cosmetic nature, pitting, slipped, over fettled etc. Nothing that couldn't be sorted with a little ingenuity. But shouldn't be sent off to a customer expecting them to deal with !!

Pictures of the start of the gearbox in the next post.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on September 17, 2017, 09:17:00 PM
First picture.

Getting ready to bring the chucking stub to size.

Second picture.

Facing off with a C 15 radius Carbide tipped tool.

Third picture.

Casting reversed and chucking stub made to exactly the same diameter as the other one.... There's a good reason!

Fourth picture.

Squaring the parting off tool.

Fifth picture.

Steady as she goes!

Sixth picture.

Phew, thank goodness that's over with.

Seventh picture.

All faced and ready for the next operation.

Cheers Graham.



Title: Re: A Robinson from rejects.
Post by: Jasonb on September 18, 2017, 07:31:00 AM
Graham asked if I could add some of the drawings to give people a better idea of what he is doing, this is the one that covers the gearbox.

The idea of this design is that the epicyclic gear means that the eccentric will rotate at half the speed of the crank. This gives a more compact arrangement than teh usual 1:2 gears found on most hit open crank engines and the cam driven off the larger gear is done away with. Also everything is enclosed so you won't get more grease on your chips that you should.
 
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on September 18, 2017, 11:24:57 AM
Good morning Jason.

Many thanks for posting the above, it took me way back!

I spent hours, nay days doing those drawings, there'll be youngsters reading this thread that could probably have the whole set done in a matter of minutes. In 3D to boot!

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on September 18, 2017, 08:51:24 PM
Gearbox continued....

Picture 1.

Nice and snug.

Picture 2.

What'll do a lot 'L do a little!

Picture 3.

Aren't Thou's confusing? 11 mm offset found.

Picture 4.

Boring the crank pinion rear support.

Picture 5.

Ah, perfect. Go in before things change!

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Ye-Ole Steam Dude on September 18, 2017, 09:53:55 PM
 Looks like it is coming right along and I am enjoying following the progress.

Thomas
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on September 19, 2017, 08:56:11 PM
Thanks Thomas.   :ThumbsUp:

Gearbox almost concluded....

Picture 1.

Is it a lathe, is it a mill? Roughing out with an end mill.

Picture 2.

Gear pocket finished to size.

Picture 3.

The reason for making both chucking stubs the same diameter. Gearbox cover being drilled, no need for marking out just slacken and tighten the same two chuck jaws!

Picture 4.

Hole bored to clearance for crank pinion.

Picture 5.

Back to the 3 jaw to clean gearbox cover plate.

Picture 6.

After careful removal of the chucking stub final light cuts and an emery.

Picture 7.

Not much to look at now, is there?   :)
Title: Re: A Robinson from rejects.
Post by: Jo on September 20, 2017, 02:35:35 PM
Graham asked if I could attach the full set of pdf drawings for this engine and the build notes. (I have also attached a copy of his broadsheet).

 :thinking: I seem to have found a space that is crying out for a set of these castings  :)

Jo
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on September 20, 2017, 06:14:20 PM


 :thinking: I seem to have found a space that is crying out for a set of these castings  :)

Jo

Thanks Jo.  :ThumbsUp:

I hope that space has a reinforced base?   ;)

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Jo on September 20, 2017, 06:43:32 PM
I hope that space has a reinforced base?   ;)

At 14Kg it will be one of the heaver set of castings but I can cope  ;D

Castings   :cartwheel: castings   :pinkelephant:

Jo

P.S. As you can see Surus my Elephant also has a passion for castings  ;)
Title: Re: A Robinson from rejects.
Post by: Jo on September 21, 2017, 04:43:40 PM
:naughty:

I've been told one of these sets has my name on it  :whoohoo:

Graham I know someone is allergic to that special brown coating that you have been using to protect these castings so for his sake it is probably best that he avoids these  ;) After all we know he doesn't like castings and especially bits of metal with that special protective coating... be careful if he tries to talk you out of one you will never hear the end of it  :disappointed: ... by far the worst one is the cylinder casting: look at it the protective coating, the casting is so nicely aged that it is almost falling off  :facepalm:

Jo
Title: Re: A Robinson from rejects.
Post by: Jasonb on September 21, 2017, 05:06:32 PM
Too Late Jo there is something on its way to me shortly from Graham :LittleDevil:
Title: Re: A Robinson from rejects.
Post by: Nick_G on September 21, 2017, 05:37:16 PM
:naughty:

I've been told one of these sets has my name on it  :whoohoo:


.
You will be making a nice trio of door stops Jo as this one will keep the started but never finished R&B and Centaur company.  ;) ;) >:D



Nick  ;)
Title: Re: A Robinson from rejects.
Post by: Roger B on September 21, 2017, 05:42:48 PM
The R&B was finished but never started  :)  :)  :)  :wine1:
Title: Re: A Robinson from rejects.
Post by: Jo on September 21, 2017, 05:45:57 PM
The R&B was finished but never started  :)  :)  :)  :wine1:

Very true Roger  :( like over 50% of R&B's, as there is a flaw in the drawings. the problem is that no one has yet documented what is wrong

Jo
Title: Re: A Robinson from rejects.
Post by: Nick_G on September 21, 2017, 05:48:38 PM
The R&B was finished but never started  :)  :)  :)  :wine1:
.
Has anybody ever tried to start it.?  :) :) :) :wine1:

Because unless it has run it ain't finished is it.  ;)

Nick
Title: Re: A Robinson from rejects.
Post by: Jasonb on September 21, 2017, 05:53:44 PM
The R&B was finished but never started  :)  :)  :)  :wine1:

Very true Roger  :( like over 50% of R&B's, as there is a flaw in the drawings. the problem is that no one has yet documented what is wrong

Jo

But that does mean 50% have been made to run, can't you work out whats wrong rather than waiting for someone else to tell you what it is?

Nick, I did have a bit of a go to get it running but when it drew blood I did not offer again. :ThumbsDown:
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on September 21, 2017, 05:58:03 PM
I would be very happy to look into the non starting issue.

There hasn't been an engine I haven't managed to get going, even the most stubborn.

The offers open.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Jo on September 21, 2017, 05:59:59 PM

But that does mean 50% have been made to run, can't you work out whats wrong rather than waiting for someone else to tell you what it is?

Nick, I did have a bit of a go to get it running but when it drew blood I did not offer again. :ThumbsDown:

As I cannot move the thing on my own I have not bothered to do anything more with it. I have put it in a warm dry place to keep it safe.

I also have a rule that I do not try running engine on my own... it is all about safety. If it does go wrong then you need someone to either admister first Aid or to run you to the hospital. Surus is no good at that yet  :-\

Jo

Title: Re: A Robinson from rejects.
Post by: Jasonb on September 21, 2017, 06:04:27 PM
You could just pop the flywheels off then it could be carried to the workshop and the flywheels put back on.

I do that with all the big hit & miss engines - leave the flywheels loose as I bring the engine that I am working on in from the workshop and up stairs to my study at the end of the day - saves having anything getting nicked or going rusty.

J
Title: Re: A Robinson from rejects.
Post by: Jasonb on September 21, 2017, 06:06:25 PM
Quote
P.S. We all have engines that don't run, don't we Jason

But some of us have far more non running and unfinished engines than others, don't you Jo, I could list yours but would need to take my shoes and socks off :LittleDevil:
Title: Re: A Robinson from rejects.
Post by: Nick_G on September 21, 2017, 06:10:57 PM
.
Suck-squish-bang-blow.  :ThumbsUp:

Or am I confusing engines with something I 'may' have read in the Kamasutra.?????  :D  :-[ ;) ;)

Nick
Title: Re: A Robinson from rejects.
Post by: b.lindsey on September 21, 2017, 08:05:47 PM
Graham, I have been looking in on this project from time to time and find it a most interesting engine. Not to intrude on the positive comments made about the build so far and the useful information provided, but please folks, let's keep the personal stuff off thread. I know we all like to poke fun at each other and that goes for this side of the pond as well, but please....lets keep in mind that we have added over 100 members this month alone so far, many of them new to this hobby and forum, and we all need to continue upholding and promoting the friendly, welcoming,  and positive atmosphere that all of us as forum members have worked so hard to build and maintain. Sometimes it good to read a reply before hitting the send button in the context of how it might read to guests and especially new members. I have done the same so I am not guiltless either, but we all need to strive to keep MEM the best of the model engine forums.

Bill
Title: Re: A Robinson from rejects.
Post by: Vixen on September 21, 2017, 08:14:05 PM
+1 behind Bill,

Lets keep it nice folks
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on September 21, 2017, 08:27:18 PM
Ok. Back on topic.

The internal gear at first seemed to be a real obstacle.....

A little over an hours work in the foundry area.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: crueby on September 21, 2017, 09:23:35 PM
Ok. Back on topic.

The internal gear at first seemed to be a real obstacle.....

A little over an hours work in the foundry area.

Cheers Graham.
Those look great, but I got a bit lost on how you made the internal gears - did you use a normal outside gear as part of the mould? How was the master made if it started as an internal tooth gear?   :headscratch:
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on September 22, 2017, 11:43:10 AM
Hello crueby.

The gears in the photograph are " in the rough " so to speak. I send them with the bulk that provided the pressure to form good tooth definition at the bottom of the die.

The die consists of 3 parts, the base ( first part ) that locates both outer ring ( second part ) and the tooth form ( third part ) in correct alignment to create the eccentric.

The base and ring both being made of Cast Iron. The tooth form was/is a standard 1.75 MOD spur gear attached to a shaft with a taper given to it above the gear. This taper makes it easier to remove it from the Zinc casting as it's cooling. I also carefully ground minute grooves under the gear to allow the trapped air to escape. This " sharpens " the edge of the casting.

I usually end up scrapping/re melting the first couple as the die seems to work better as the temperature increases, after that it's akin to " shelling peas " ... Melt, clean, pour, remove and repeat. You need really good quality foundry gloves though!

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Jasonb on September 22, 2017, 01:26:33 PM
Mould shown on the top right of this photo, just pour in the metal and it forms around the offset gear and above it.

(http://www.modelenginemaker.com/index.php?action=dlattach;topic=7440.0;attach=71652;image)

I may be wrong but a true internal gear should have a slightly different profile to just the negative image of a spur gear but for the loads and speeds this engine will see I doubt it makes any difference.
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on September 22, 2017, 02:40:20 PM
Hello Jason.

Not wrong at all....

It's one of the reasons for the choice of a larger tooth form. And as you wrote the load is little more than compressing the spring of a ball point pen !!

Cheers Graham.

Title: Re: A Robinson from rejects.
Post by: crueby on September 22, 2017, 03:14:31 PM
Slick setup, thanks for the explanation on the mould!
Title: Re: A Robinson from rejects.
Post by: Jo on October 03, 2017, 09:39:49 AM
Hi Graham, I've been redrawing up the X Type drawings in Alibre..... There are a few what we term "features" in the drawings  ::)

Just finished drawing up the Ignition tube and Chimney but still not sure how it works  :headscratch:

Jo
Title: Re: A Robinson from rejects.
Post by: Jasonb on October 03, 2017, 10:10:25 AM
You will need to add a small burner to the 11mm hole Jo otherwise your hot tube will stay a cold tube. Apart from that it works like a hot tube, think of the tube like a glow plug, when it is heated by the burner stays hot just like a glow plug on an aero engine. Fuel/air mix when compressed in the cylinder and up into the hollow tube will ignite.
Title: Re: A Robinson from rejects.
Post by: Zephyrin on October 03, 2017, 10:39:10 AM
Thanks for documenting the die and the moulding process, lot to learn.
A nice and interesting engine, even if the gears are not visible while running !
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on October 03, 2017, 11:37:26 AM
Hi Graham, I've been redrawing up the X Type drawings in Alibre..... There are a few what we term "features" in the drawings  ::)

Just finished drawing up the Ignition tube and Chimney but still not sure how it works  :headscratch:

Jo

Hi Jo.

Hmmm... Alibra.... Nothing to do with Tee and Set squares then?   :) How easy it is these days!

" Features " ? Could you elaborate please?

Hot tube ignition was considered to be the most reliable form during the early years of engine manufacture, particularly with engines that used a gaseous fuel.

Jason has pretty much summed up the MO.

As time progressed and manufacturers began increasing compression pressures to increase power output it soon became apparent that " preignition " was a real issue. Some makers employed mechanically actuated valves to open the ignition tube at the right time. By this time " electric " ignition had become far more reliable and began to replace the heated tube method.

Thought of the day....

" Chauffeur " ?? Goes right back to the early IC engine era.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on October 03, 2017, 11:55:52 AM
Hi Zephyrin.

You're welcome.

After the success of the cast gear for the Robinson engine I started to look at other " gravity cast " items.

I made many Steel moulds for both the big end and main bearings for my Gardner model, the original, later engines used " Babbit " metal, the Zinc looking very authentic indeed! The real beauty is that by factoring the shrinkage the outside of your part will fit without any further machining.

Being such a low melting point metal it's easy to create intricate castings with fantastic detail.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Jo on October 03, 2017, 01:10:15 PM
" Features " ? Could you elaborate please?

A couple of measurements that when drawn to dimension don't look like your original drawing  ::).... Measurements crossed out and not replaced and the use of 1/6th as an imperial measurement fraction :Lol:

When I have finished putting the bits together I will lay them out in 2D and attach them to the thread, in nice modern measurements  ;D. Yes I know I have invented unique measurements for all those "as cast" dimensions which may be wrong  ;)

Jo
Title: Re: A Robinson from rejects.
Post by: Jasonb on October 03, 2017, 01:19:42 PM
Why not wait until you have the castings in your hand then you can take sizes off of the actual part rather than make things up?
Title: Re: A Robinson from rejects.
Post by: Jo on October 03, 2017, 01:24:25 PM
Why not wait until you have the castings in your hand then you can take sizes off of the actual part rather than make things up?

That would mean waiting until a week before I may have to return to work  :facepalm: :hellno:

Jo
Title: Re: A Robinson from rejects.
Post by: Jasonb on October 03, 2017, 01:27:03 PM
You could fill in the time completing the Otto drawings that you were going to do while off sick :LittleDevil:
Title: Re: A Robinson from rejects.
Post by: Jo on October 03, 2017, 01:29:04 PM
You could fill in the time completing the Otto drawings that you were going to do while off sick :LittleDevil:

There are four more items left to finish those and there is also the Scorpion drawings underway.

Jo
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on October 03, 2017, 02:23:58 PM
Hi Jo.

I'm looking forward to seeing the fruit of your labours.

I'll be going back to the workshop in a few days to continue my build but I'm beginning to think I should have used a couple of plurals in the title of this thread!   ;) I have a feeling that there will be a few more contributors joining us come November.

The Robinson is really quite a simple engine to build, in fact one of my former customers built his with just a Drummond roundbed lathe and a pillar drill!

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Jo on October 05, 2017, 05:04:30 PM
Look what I just found  :naughty:

Now this Sphinx seems to have my name on it  :mischief:

Jo
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on October 05, 2017, 05:47:01 PM
 :lolb:

Look at the highly professional date change and price increase !

My goodness, the year our youngest was born.

I hope you're joking Jo? But I might just have the last laugh.... >:D

Need any help in the garden?? Perhaps a Gardner....  :naughty:

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Jo on October 05, 2017, 06:32:17 PM
I am looking to employ a gardener due to :old:

But I still think there are not enough Sphinx's in the world  ;)

Jo
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on October 05, 2017, 08:11:28 PM
Well....

Here's the very first one, slightly modded over time.

0pxNlFMT24I
Cheers Graham.

Title: Re: A Robinson from rejects.
Post by: Jasonb on October 05, 2017, 08:31:34 PM
Graham, is that a burner "ring" at the bottom of the hot tube?

On the valve I assume the exhaust seat is machined into the right hand end and the inlet valve seats on the end of the screw in brass part to the left.
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on October 05, 2017, 09:13:47 PM
Hi Jason.

Right on the nose !!   :)

Over the years I learned a few tricks.... The gas ring is quite simple, a hollowed out " doughnut " with a press fitted Brass disc with lots of holes. The trick is the gas/air mix...
Into the side of the burner ring is a passageway that connects to a proprietary made gas burner like Sievert etc. This ensures a perfect mix to burn from the ring !!

The side mounted exhaust valve chest is loosely based on the Robinson, but with twist, I decided to put the air/gas valve into the other end instead of a separate/different location.
This was my second freelance design so simplicity of build was still paramount. As we learned so we grew.

Cheers Graham. 
Title: Re: A Robinson from rejects.
Post by: Jo on October 08, 2017, 05:08:56 PM
Ok Graham how do you drill for the little end pinch bolt  :noidea:

I think I might be tempted to Loctite the bush in  ;)

Jo
Title: Re: A Robinson from rejects.
Post by: Jasonb on October 08, 2017, 05:20:08 PM
Simples you use a necked bolt, I've done them on a couple of engines :)

Drill and tap right through from the cylinder head end of the rod. Then make a bolt with the upper part of the shank just below minor dia of the thread
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on October 08, 2017, 05:58:19 PM
Ok Graham how do you drill for the little end pinch bolt  :noidea:

I think I might be tempted to Loctite the bush in  ;)

Jo

Hi Jo.

Are you making some " Robinson " swarf?  :)

I used to " dummy " that!

Do as Jason has suggested by all means but I just press fitted the small end bush and then re reamed for the gudeon pin. Or " wrist " pin in olde worlde speak.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Jo on October 08, 2017, 07:00:51 PM
Are you making some " Robinson " swarf?  :)

:hellno:

Who have you been talking to  ::)

Jo
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on October 12, 2017, 06:03:28 PM
Hi Jo.

I've PM'd you.

I thought you and other members/readers might like to see a photo of the Rhuddlan foundry where your castings were made a little over 17 years ago. We had a little trip to the seaside.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: crueby on October 12, 2017, 09:12:22 PM
Looks like the foundry itself took a trip INTO the seaside....   :(
Title: Re: A Robinson from rejects.
Post by: Jasonb on October 13, 2017, 07:32:32 AM
Returned the casting sand to it's place of origin ;)
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on October 13, 2017, 11:25:31 AM
Sorry Jason, nowhere near Mansfield!

Aye, ''twas lovely stuff to work with, I have a quarter Ton tucked away in my foundry area.

There's an irony in the above photograph, the foundry closed in 2000 and lay idle until a deal was struck with the neighbouring land owner. The princely sum of £1.00 was paid, the site had a new owner.

Some years back I approached the owner with a proposal to re open the foundry but with a twist. Steeped in history the site had been running since 1850 as a producer of agricultural equipment. Corbett Williams was their name.

The idea was to open as a tourist attraction with practical demonstrations of the dying art of foundry work.

The owners were greedy wanting a £40,000 a year rental! No jobbing foundry would cover that cost.

The site was flattened and proposed as a housing estate, here's the irony. Tests were made of the ground only to find that the substrate was toxic. Rhuddlan foundry had been used during the Great War to make munitions. Instead of a thriving tourist attraction on the North Wales coast the site will remain just as you see it in the photograph.

Sad.
Title: Re: A Robinson from rejects.
Post by: Jo on October 18, 2017, 06:42:51 PM
Hi Graham,

How's your X Type coming on?

I've just finished my first one, ready for tomorrow   :mischief:

Jo
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on October 18, 2017, 07:23:00 PM
Lovely Jo.

Kinda reminds me of Kryten from " Red Dwarf "  missing the curvy " iney outey " bits !!   ;)

The Phoenix is stirring in the ashes....   ;)    Sneak preview.... 

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Jo on October 18, 2017, 07:32:01 PM
I prefer to be thought of as Cat..... Think episode 1: scent can and casting sets  ::)

 :embarassed:

Jo
Title: Re: A Robinson from rejects.
Post by: Jasonb on October 18, 2017, 07:33:00 PM
You have made that faster than me Jo
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on October 18, 2017, 07:48:59 PM
Hi Jason.

Is it that easy these days?

Slight correction, if you'll allow me? The 1895 engine I scaled had the writing on the reverse side and on the later engines only H R was seen on the side you have projected.

In the early years what we call the front ie. mechanicals seen was termed the rear. The front was where the power came from. I'm basing this statement on early literature from R.A. Lister's manuals.

I assume these " electronic " renditions actually run as well?

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Jasonb on October 18, 2017, 08:19:50 PM
Yes it is that easy once you get the hang of things. Alterations are just a click away so no need for scratching out the ink, also the alteration done on the base casting is automatically done on the assembly drawing and anywhere else it may appear such as the 2D drawings.

You know my engines run ;) once it is all drawn it will be possible to hold the mouse down on the flywheel and see all the parts move as you drag the flywheel round or click the piston and see the parts turn as you slide it up and down. It is quite handy when designing an engine as you can see things that may hit
Title: Re: A Robinson from rejects.
Post by: Jo on October 31, 2017, 12:25:39 PM
It seems Surus has a new friend who sends him castings and Drawings ::)

Jo
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on October 31, 2017, 03:20:44 PM
Hi Jo.

The system worked then?

You must let me know what you think of the drawings?

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Jo on October 31, 2017, 04:09:16 PM
The drawings look like they have been stored in the same place as your castings  ::) I won't be studying them in any depth until I go back into the office and they make friends with the scanner  ;)

Surus tells me he is hoping to swop his latest 4 castings for a set of Ploughing engine cylinder castings tomorrow  :noidea:

Jo
Title: Re: A Robinson from rejects.
Post by: Jasonb on October 31, 2017, 04:19:51 PM
Is that your BB1 cylinder that did not come back with the OL ones?
Title: Re: A Robinson from rejects.
Post by: Jo on October 31, 2017, 04:44:55 PM
 :ShakeHead: I have that.

Jo
Title: Re: A Robinson from rejects.
Post by: Jasonb on October 31, 2017, 05:05:49 PM
I thought it did not come back with the first lot of castings, maybe you got it with the recast cylinders

So what you going to do with another one?
Title: Re: A Robinson from rejects.
Post by: Jo on November 01, 2017, 02:07:50 PM
So what you going to do with another one?

 :headscratch: Its a casting. What do I normally do with castings  :naughty:

Jo
Title: Re: A Robinson from rejects.
Post by: Jasonb on November 01, 2017, 02:22:00 PM
That top cover looks a bit angular for a Fowler and it has round bosses for the regulator not oval, you have also hidden the side of the cylinder that may have the valve rod gland bosses and all in nasty gum metal :(

Back to the main subject matter, this one popped up on Youtube, it has a handy extra part that you may want to add to your Robinson :ThumbsUp:

7qTcZoLuVmc
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on November 01, 2017, 06:41:08 PM
Now, now Jason....

However, my Robinson is the only one that ever bit me hard.... my fault really as one should never, ever clean an engine whilst itís running. Took the end of my forefinger clean off without a miss!

Actually most Robinson related maiming has been caused by getting ones thumb caught between the flywheel rim and top of the water base.... whilst starting.

The crank guard, a heavy casting was only fitted, at least as far as Iím aware to the suffix ď P ď engines. P being a Petrol version that used Magneto ignition, the Magneto sitting above the crankshaft.

The engine in the video belongs to Geoff the curator of the Anson Engine museum.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: RayW on November 04, 2017, 10:05:30 AM
Well, it just had to happen. Following my visit to the Anson Museum and meeting with Graham, I have now joined the "Robinson from Rejects" gang!
I have already been following this thread with interest and will be adding my own contribution as my build progresses.
Looking forward to seeing Jo's drawings once they are finished.
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on November 04, 2017, 11:53:58 AM
Hi Ray.

Welcome aboard.

I too am eagerly waiting to see the new, improved drawings, since the originals have been misplaced. :-[

I must get back into the workshop and finish the epicyclic gearbox, just the commercially made gear to modify and fit, left to do.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Ian j on November 17, 2017, 06:46:24 PM
Hi everybody.
On one of my visits to the Anson Engine Museum they had the Robinson Engine in Jasonís video running & I was really taken by it (maybe because it was related to chip shops! ) It soon became obvious the castings were no longer available but on studying the examples at the museum & the plans I thought it was possible to fabricate the engine from bar stock, but the stumbling block would be the internal gear for the gear box.
I made contact with Graham via this web site who said the gears were cast in house & he was prepared to cast one for me & would be at the Anson Museum at the end of October, so I made a start .
  The engine bed is fabricated from Aluminium plate, the two sideís milled to shape & then using 6BA screws & JB weld assembled to the internal stretchers, back & bottom. The crank shaft runs in bronze bearings. While I was building this Graham contacted me to say he had a number of ď reject " castings and would bring them along to the museum. This made me re think my build but I decided to carry on with mine using the casting for the basic details & then build a second engine from the castings.
 The cylinder is milled/turned/bored from a block of HE30 aluminium still to do the piston and liner. Graham you say to use Araldite or Loctite 638 to secure the liner   would JB weld original be suitable as I find Loctite is a bit to fast for me!
 Thatís it for now, a big thank you to you Graham for the gears and castings.

Ian
Title: Re: A Robinson from rejects.
Post by: Jasonb on November 17, 2017, 07:49:46 PM
You're off to a cracking start.

I think it would be a bit harder to ensure an even thin coat of JBWeld to get a good seal around the liner, the good thing with Loctite is that it will wick around the joint and completely fill it. If you don't make the liner too tight then you will have a bit more working time before it goes off, I tend to use 648 myself.
Title: Re: A Robinson from rejects.
Post by: Ian j on November 17, 2017, 08:36:21 PM
Thanks for that advice Jason.
Title: Re: A Robinson from rejects.
Post by: Jasonb on November 26, 2017, 06:05:25 PM
I finally got my grubby little mitts on a reject cylinder casting so thought I had better see what was hiding beneath the "patina". All I can say is if this was  a reject then the ones that went out to customers must have been very good.

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02290_zps9jqk7glw.jpg)

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02291_zpspbvkh5p8.jpg)

J
Title: Re: A Robinson from rejects.
Post by: Jo on November 26, 2017, 06:10:21 PM
I thought you already had three other engines on the go yesterday....  :noidea:

I see you like Graham's brown protective "red oxide" coating so much you have decided to keep it :naughty:

Jo
Title: Re: A Robinson from rejects.
Post by: RayW on November 28, 2017, 05:38:45 PM
Finally made a start on the Robinson this week. The photos show the main casting and cylinder block loosely assembled. Both are part machined at this stage and the next big job is to figure out how best to bore out the cylinder block for the liner. I am undecided at the moment as to whether lathe or mill would be the best way to go. I suspect that it will have to be the lathe as I doubt if there is sufficient headroom on my little mill to accomodate the casting and the boring head. Either way, centering the casting and holding it securely will be crucial.
The other main job left to do on the cylinder casting is to mill out the big rectangular hole in the base as illustrated by Jason.
Title: Re: A Robinson from rejects.
Post by: Jo on November 28, 2017, 06:51:58 PM
I see Graham let you have a batch of castings with his trademark protective coating too Ray.

I am pleased to say mine has worn off  ;)

Jo
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on November 29, 2017, 11:56:18 AM


I am pleased to say mine has worn off  ;)

Jo

Waaaaay tooooo much fondling Jo!  ;)

I must apologise to all, the forum moves so fast I'd completely missed Ian's contribution and progress, it's looking great.

I'm currently working on an unusual project at the moment....

PmjGtZM21YM
This may be featured in a BBC Radio 4 presentation in the near future.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: RayW on November 29, 2017, 05:39:58 PM
As Graham says Jo, definitely too much fondling has worn off all that lovely patina!
Spent today working out the set-up for boring the cylinder. As I suspected, there was just not enough headroom on the mill for the casting and a boring head and boring bar, so switched my thoughts to lathe set-up. Finally came up with the method as shown in the photos. I machined an aluminium plug to fit the cast main bore with a reduced diameter at one end to locate in the cast hole at the front end of the cylinder casting. I then bored through to accomodate a bar which was of the correct diameter to fit the bore of the lathe spindle with the other end being held in the tailstock chuck.
With the casting thus located centrally, it was just a case of bolting it to the faceplate. To attach the casting to the angle plate I drilled and tapped a hole in the base, in the area which will be milled out later. Because I could only use one bolt, two other bolts were located through the angle plate either side of the casting to prevent any possibility of the casting swivelling while being bored.
Title: Re: A Robinson from rejects.
Post by: Jasonb on November 29, 2017, 08:26:22 PM
You beat me to it, I was going to post that it may be better to do the bottom recess after boring as you could tap into the metal.

I opted to drill and tap for a couple of M6 studs either side of the opening so I could mount it to an angle plate

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02292_zpsddd4cqns.jpg)

I glued a scrap of ali to the front of the opening and punched that so I had something to locate, As the outside of the bottom of the casting had been skimmed that gave me square faces to line up to the faceplate. It's now bored out to 1.5" ready to open up for the liner

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02293_zpsqstmrb8n.jpg)

J
Title: Re: A Robinson from rejects.
Post by: Ian j on November 30, 2017, 05:35:47 PM
Latest progress on my engine built from bar stock.
The hot tube chimney is a piece of thick walled stainless with a plate and burner tube mountings silver soldered on, hope it doesn't all falls apart from the gas burner heat!
 The piston is machined from cast iron bar as is the liner. I took your advice Jason regarding using loctite, I also reduced the o/s diam. of it for the length of the cut out in the cylinder casting which made it easier to apply the loctite and insert the liner. I let it cure for 24hrs and when assembled on the bed with a gasket it all seemed to be water tight. Whats the purpose of the 1/16" deep part on the bottom of the cylinder?
 When I machined the the cylinder I used a keates angle plate on a face plate, but it was just a block of ali.at that point so no awkward shapes to consider. When I do the "real" one using the castings both Ray's and Jason's methods will be a great help.
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on November 30, 2017, 05:55:58 PM
Hello Ian.

Amazing progress, well done!

Ray PM'd me yesterday with the very same question, what's the idea of the step underneath? Well we thought, at the time that getting water closer to the glued joint might be advantageous. It is the hot end after all!

I'm smiling, as I used to just put the cylinder casting into the mouth of my 4 jaw and bore away. I guess having the space for a large machine has its advantages.

I had a recurring customer that worked for GEC in their massive machine shop. I once asked how he bored his cylinders, his reply, oh, I just bolt them down on the table and stick an end mill in!!

Cheers Graham.

Title: Re: A Robinson from rejects.
Post by: Jasonb on December 02, 2017, 08:10:10 PM
I'm not sure that this special coating that some people keep going on about is all it's cracked up to be, seems to have worn off my casting already :-\

Just a couple of holes left to do but they will have to wait until the liner is in place as they pass through both the liner and cylinder casting.

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02299_zps5xhvmjfm.jpg)
Title: Re: A Robinson from rejects.
Post by: RayW on December 02, 2017, 08:57:18 PM
You are making good progress Jason.
I am on hold with boring the cylinder at the minute as none of my boring bars was doing a very good job so have ordered an indexable carbide tipped one as I want a really good finish where the liner has to fit.

Ray

P.S. Don't forget the vertical exhaust slot and the hot tube holes. They don't go through the liner!
Title: Re: A Robinson from rejects.
Post by: Jasonb on December 02, 2017, 09:01:55 PM
You are right Ray they go into the 1.5" bit at the end, could have done them :embarassed:
Title: Re: A Robinson from rejects.
Post by: Jo on December 03, 2017, 11:26:00 AM
I'm not sure that this special coating that some people keep going on about is all it's cracked up to be, seems to have worn off my casting already :-\

Too much fondling  ::)

I hope the other three engines are still moving forward.

Jo
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on December 03, 2017, 11:39:27 AM
Hi Jason.

Oooh, is that a bit of shrink I can see in your photo?

This was a major problem with the earlier Rhuddlan castings, I hope it doesn't extend into an area that can't be mended?

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Jasonb on December 03, 2017, 12:01:04 PM
Yes as it was right where the remains of the riser could be seen so I had assumed that was the problem, about to go and mill it out so will report back later but I can't see it on the inside so fingers crossed.

Jo it was only a few mins of fondling that caused it to ware off, do you think I should be using silk gloves rather than a grinding bit in the Dremel?  Yes the others are moving a lot faster than some of yours :LittleDevil: This one will probably get put away now as I did not want to spend the time and effort drawing and fabricating the other parts if the cylinder was not going to be upto the job, infact had the cylinders not become available this was going to be quite a way down the list of engines to do.

J
Title: Re: A Robinson from rejects.
Post by: Jasonb on December 03, 2017, 04:57:52 PM
Exhaust passage machined up OK, also did the hole for the hot tube while I was at it.

Then I thought what use is a hole without something to put in it so made the hot tube and plate that retains it.

J
Title: Re: A Robinson from rejects.
Post by: RayW on December 09, 2017, 03:28:47 PM
As Graham knows, I had a bit of a traumatic time machining the exhaust valve chest due to several senior moments on my part.
I had some difficulty reading the bore dimensions on the scanned copy plans, so messaged Graham and confirmed that my readings were correct. I then, for some reason, proceeded to bore out to completely the wrong size ( 7/16" instead of 5/16")!
Fortunately, I was able to rectify the situation with a press fitted cast iron plug held in with Loctite, then re-bore to the correct dimensions.
The exhaust valve assembly is now almost complete. I just need to cut the valve seat and grind in the valve, and machine a couple of flats on the spring collet.
I have also finished boring the cylinder ready for the liner, which will be the next job.


Title: Re: A Robinson from rejects.
Post by: Jasonb on December 09, 2017, 05:02:04 PM
I got the cylinder liner roughed out in the week and finished it off last night followed by honing and then stuck in in today with 648.

Thought I might as well do all the bits on that page of the drawing so made the chimney and cap too. Burner spigot is still overlength and under bore until I get the burner sorted.

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02315_zpsnfvwydwj.jpg)

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02317_zpsjamutkdw.jpg)
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on December 09, 2017, 05:28:22 PM
Very nice work, both!

The Robinson is a fairly simple engine with few components, I'm wondering if we'll be seeing a runner before the year is out?   :)

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Jasonb on December 10, 2017, 04:56:11 PM
I remembered that I had a spare iron piston casting that was in the box for another set of engine castings that had been through several peoples hands so someone must be missing a piston. It also happened to have "RO" cast on the outside so I thought it rather fitting that it would get used on a Robinson engine. While I was at it I also did the wrist pin and sq headed screws to retain it.

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02319_zpsmjlmaciv.jpg)

And just so Jo won't moan that I have been neglecting my other engine projects I made a start on the little between ctrs boring bar that I will need for the Otto's cylinder :)

YwxXUqaWLlM
J
Title: Re: A Robinson from rejects.
Post by: Jo on December 10, 2017, 05:21:45 PM
:headscratch: That's less than 40mm diameter why not put it through the nose of the lathe.

Looks like its quality steel by the haze coming off the tip. Have you thought about how easy it will be to machine for the tip?

Jo
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on December 10, 2017, 05:25:00 PM
 :lolb:

You lucky, lucky  :censored:  " Life of Brian " quote.

That WAS a genuine Robinson piston casting, in fact the part number was RO 4 but the number fell off years ago.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Jasonb on December 10, 2017, 05:44:49 PM
:lolb:

You lucky, lucky  :censored:  " Life of Brian " quote.

Always seem to come up smelling of roses :LittleDevil: There was another casting in teh same box that look like it came from the same foundry as the piston, I'll take a photo and maybe you can identify that too.

Jo I can only pass 1" through my spindle, yes quality stuff with the green paint still on the end and none of that rusty brown coating as it came from a reputable steel stockists. It machines very nicely as I also used a bit for the X-types chimney top as 35mm is near to 1.375 as makes no difference and all the EN1A I have had from Ringwood Metals (http://ringwoodmetal.com/steel/bright-steel-bar/round.html) in the past has been easily worked. Smoke was more likely down to the crappy Bangood tip I was trying out though the finish was not too bad for the finish cut when I reduced the depth of cut

(http://img.photobucket.com/albums/v156/jasonballamy/Engineering/Otto%20Langen/DSC02320_zpsj23n7lqe.jpg)
Title: Re: A Robinson from rejects.
Post by: Jasonb on December 10, 2017, 06:03:32 PM
just looked at the photos Jo posted of the castings and the other one I have is the disc of material for the gearbox but less rusty Double Lucky  :censored:
Title: Re: A Robinson from rejects.
Post by: RayW on December 13, 2017, 09:18:57 AM
Still following on Jason! Got the hot tube and burner assembly finished yesterday. Have left the bore for the burner undersize for the time being until I get the burner itself, then will bore to suit.
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on December 13, 2017, 12:08:47 PM
Good morning Ray.

She's coming along nicely!

With regard to the burner for the hot tube ignition it seems that Primus has become Sievert since I last purchased bulk orders. The 8842 is readily available at nearly £20.00 ( found on eBay) a far cry from the good old days!

The downside to this method is that it requires a high pressure gas supply wheras the engine only needs a few PSI at the inlet valve. A dual fuel line is the obvious approach but, to my mind, looks wrong.
My method was to bring a single line from an adjustable HP Propane regulator then split off just before the fuel control valve/tap.

Wade did a range of Brass compression fitting needle valves, I used the 3/16" version with the rather awful looking plastic knob removed. The beauty of this was the fact that the compression nuts and olives were at 1/8" BSP. My trick was to soft solder over the end of the Copper pipe that fed the fuel control and then with a sharp needle pierce through the solder to make a tiny hole so that a limited amount of gas was allowed to get to the control tap.

Here's some advice for all owners of " small power " LPG gas engines. The air/gas ratio is pretty narrow for the fuel wheras the old " Town gas " was far more forgiving. Having the control tap as close to the intake as possible makes getting that mix easier to achieve. If you have distance between the two the gas can build pressure between cycles and become too rich then a misfire occurs. Using this practice I always had a reliable engine start.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: RayW on December 13, 2017, 08:24:08 PM
Hi Graham,

Thanks for that advice. I know from experience both with my Otto and my Stuart half horsepower just how critical gas pressure is. Your trick with the soldered pipe end and needle piercing sounds a really neat way round the problem of the two different gas pressures that the engine needs. I have some minute drill bits which would probably serve the same purpose.
I have seen some videos of these engines with a dual fuel line set-up and it is definitely messy looking with pipes and valves everywhere. The single feed pipe will definitely look neater.

Regards

Ray
Title: Re: A Robinson from rejects.
Post by: RayW on December 17, 2017, 04:12:50 PM
The liner and piston are now finished and I am really pleased with the fit. Even with no piston rings, there is quite a bit of compression if you hold the liner upright with the bottom end sealed against a flat surface and force the piston down. I have not yet fitted the liner into the cylinder casting as I want to grind out a bit of metal from inside the casting at the top as there only seems to be the thinnest of gaps, if any, for water to get round the top of the liner, and there is plenty of thickness of material there.

I also machined the main bearing caps today and fitted them to the main body casting, ready for line boring in due course.

P.S. The grooves seen at one end of the liner in the attached photos are for the Loctite adhesive with which the liner is held in place.
Title: Re: A Robinson from rejects.
Post by: Jasonb on December 17, 2017, 04:18:05 PM
I was actually wondering how much water the top of the cylinder liner is likely to see. Looks like it will just be an air pocket to me as there is no way to bleed off the trapped air when the base if filled with water.

J
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on December 18, 2017, 06:17:12 PM
Hello All.

I'm quietly following along, been a little unwell recently and now have vertigo. Typical as the Christmas season is nearly upon us.

Regarding the air pocket, it's not too important as that's the cold end of the cylinder. However if you're worried about it my trick was to upend the engine before running, you'd hear a glug as the water displaces the trapped air.

Some lovely workmanship being presented, makes me proud to have been instrumental.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Jo on December 18, 2017, 06:27:28 PM
I'm quietly following along, been a little unwell recently and now have vertigo. Typical as the Christmas season is nearly upon us.

I find trying to pretend I am the fairy standing on the top of the Xmas tree after the second bottle of slurp does that to me too.. now I have learnt that it is safer not to have Xmas trees in the house  ::)

Jo

P.S. Hope you feel better soon Graham. Maybe a quick fondle of a set of Sphinx castings would make you feel better, I know it would me  :naughty:
Title: Re: A Robinson from rejects.
Post by: Jasonb on December 18, 2017, 06:37:37 PM


I find trying to pretend I am the fairy standing on the top of the Xmas tree after the second bottle of slurp does that to me too.. now I have learnt that it is safer not to have Xmas trees in the house  ::)

Does that mean to say you start shinning up the trees in the garden once the bottle of port is empty :LittleDevil:
Title: Re: A Robinson from rejects.
Post by: Jo on December 18, 2017, 06:57:35 PM
Does that mean to say you start shinning up the trees in the garden once the bottle of port is empty :LittleDevil:

I haven't brought any port   :facepalm:

Jo
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on December 18, 2017, 07:10:04 PM
I'm quietly following along, been a little unwell recently and now have vertigo. Typical as the Christmas season is nearly upon us.

Jo

P.S. Hope you feel better soon Graham. Maybe a quick fondle of a set of Sphinx castings would make you feel better, I know it would me  :naughty:

Well Jo.

If you can promise to be good and not become a lumberjack Father Christmas might just make arrangements with that special place he's recently found!

One thing for certain there won't be any " special " coatings to remove!! :)

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: RayW on December 18, 2017, 07:34:15 PM
Hi Graham,

Sorry to hear that you have been under the weather lately and hope you will be fit for the festive season.
Good point you make about the upper part of the cylinder being the cooler part. Perhaps I am worrying unduly about needing to open out the water space above the liner.

Best wishes

Ray

Title: Re: A Robinson from rejects.
Post by: Jasonb on December 22, 2017, 10:16:45 AM
A question for Graham.

The drawing for the inlet valve chest shows 7No 1/8" holes which I have shown on my drawing. These seem larger than on your drawing where they look to be nearer to 1/16" dia, could you shed any light on what will be best please.

J
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on December 22, 2017, 11:06:33 AM
A question for Graham.

The drawing for the inlet valve chest shows 7No 1/8" holes which I have shown on my drawing. These seem larger than on your drawing where they look to be nearer to 1/16" dia, could you shed any light on what will be best please.

J

Hi Jason.

I probably used a stencil for those, but yes 1/8Ē is correct.

Being a flat valve it takes  a little care and time to grind in as this valve also controls gas admission. I will stress that this valve will almost certainly weep no matter how careful you have been!

Cheers Graham.                                                           
Title: Re: A Robinson from rejects.
Post by: Jasonb on December 22, 2017, 11:19:49 AM
Thank you Sir
Title: Re: A Robinson from rejects.
Post by: Jasonb on January 07, 2018, 03:42:40 PM
Got the valve and valve chest done. I opted for a ring of 3.0mm holes as 1/8" looked a bit close for comfort.

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02443_zpsx62s1wy8.jpg)

And also made a start on the gearbox as I had that casting. Parted off quite nicely, I used the ctr for support until the last 5mm or so.

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02442_zpsaftetwkl.jpg)

Graham, if you are looking in could you clarify a dimension on the gearbox drawing. As I read it the peg hole to stop the gearbox rotating should be 7/16 from vertical and where a 3/4" radius arc swung from the crankshaft ctr line meet.

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/507_zpsrn99pcb1.jpg)

J



Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on January 07, 2018, 06:02:48 PM
Hello Jason.

That reads about right.

The way I used to do the final fixing of the gearbox was to drill the retaining peg hole and then offer the whole assembly to the engine. Slide the crank gear onto the crankshaft right up against the bearing then screw in the slide into the exhaust valve chest. You can now rotate the gearbox assembly till it looks right.
Using a transfer punch dot the base for the peg position.

The crank gear is drilled and tapped to 4 BA and a dome head screw is used to fix the position in the 1/8Ē keyway. Once youíve set the valve timing by removing the eccentric halftime gear and repositioning until satisfactory that assembly will always be in time because of the crank gear locking screw.

The inlet valve chest looks superb, almost identical to the casting!

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Jasonb on January 12, 2018, 05:59:17 PM
So this weekends homework is going to be having a go at cutting a test internal gear. I managed to find a 12T spur gear and 24T internal gear on Grabcad and imported the STL and Solidworks files into Alibre and then scaled the two so they were the right size for 1.75MOD

I'm going to take a leaf out of Willy's book and do a test one in perspex using a single point tool in the mill and will use the quill to feed it like a slotting head. gera will be on teh rotary table, having a 72:1 table to play with from ARC will make the 24 divisions an easy 3 turns of the handwheel. I can then slip the spur gear onto a 1/2" bar held in a coller and rotate the table to check the mesh of the two gears. Well that's the plan anyway.

may also make teh eccentric strap which will be in steel so I can silver solder it up from a couple of bits

Title: Re: A Robinson from rejects.
Post by: Ian j on January 13, 2018, 02:36:34 PM
A bit more progress on my engine built from bar stock/scrap!

Eccentric strap:-
I bored the centre of the rectangular lump of brass for the gear to be a close fit and then made a jig ( or is that a fixture?) to mount it on the rotary table on the milling machine table, it then only took a short time to mill the outside profile.
 The brass blank wasn't wide enough to include the oil quill so I used one of the scrap pieces produced after milling the outside profile which had the correct radius and silver soldered it on ( not exactly an invisible joint)
 I think I'm quite pleased with the end result.
Title: Re: A Robinson from rejects.
Post by: RayW on January 13, 2018, 04:18:28 PM
Very nice work Ian.
I am currently working on the connecting rod, but at a standstill at the moment as the awful plastic gears in my milling machine have just stripped for the umpteenth time, so I have ordered various replacement gears and sundry other parts from ArcEurotrade to keep me going.
I have also bitten the bullet and ordered a very professional looking belt drive conversion kit from a guy in Turkey. The kit is not cheap but looks very well made and will not only solve the stripped gear problem, but also enable the mill to run a lot quieter and faster than with the current gearbox.
Title: Re: A Robinson from rejects.
Post by: Jasonb on January 13, 2018, 08:16:35 PM
That's looking nice Ian, good to see how parts can be made in different ways if we opt out of using castings.

Well I had a go at the internal gear today, only cut half the teeth in the plastic one as that was enough to see if my methods would work

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02455_zpszjc04a7w.jpg)

So I decided to commit to some bronze. I had some 2.5" hollow bronze so the end of that was turned down to 2.308", faced and then parted off and finally the other side was tidied up to bring it to the required 5/16" thickness. As there was no middle to the bar I hot glued a bit of scrap in place so the position of the gear ctr could be marked and then picked up on the mill when clamping to the rotary table.

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02456_zpsaxzcjpgd.jpg)

To reduce the amount of metal that needed cutting out I had worked out the PCD of a ring of 4mm and 2mm holes so these were drilled every 15degrees, you can see how the gear will be eccentric by the way the drilled holes are set about the cored hole.

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02457_zpsh60bxbof.jpg)

I then milled out to the required internal diameter

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02458_zpsctfghrvz.jpg)

The cutting tool was ground freehand from some 3/16 HSS using the Alibre drawing as a template and mounted into a 1/2" bar

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02461_zpsszrlf5ui.jpg)

It was then just a case of setting the rotary table to position which was easy as the 72:1 ratio on the ARC table meant I just had to turn the handwheel 3 turns, feed the tool down using the quill lever with my right hand while feeding in the work with my left hand on the Y axis handwheel, the early cuts could be done 5thou at a time but once the end and most of the sides started to contact that came down to 2.5 and finally 1 thou cuts for the last 15thou or so. You can also see that I have slipped the pinion gear onto the tool holder and kept it out the way with a bit of tape.

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02459_zps77si4daf.jpg)

With the quill locked so the tool was below the work the masking tape could then be removed to allow the gear to drop into place and test the mesh without loosing the position of the cutting tool, it was a little tight in one spot so I lightly stoned the cutter and went round again doing a couple of spring passes in each position which did the job.

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02460_zpskxsmpo2q.jpg)

And what do you know, it even goes round and round :)

LZMHKc-3xEc
Title: Re: A Robinson from rejects.
Post by: Ian j on January 13, 2018, 08:29:58 PM
That's excellent Jason. How do you lock the quill to stop it rotating?
Title: Re: A Robinson from rejects.
Post by: Jasonb on January 13, 2018, 08:38:55 PM
I thought I took a picture of that but obviously did not :-[ I took the top cover off the mill head and clamped the gear on the quill with a couple of tool makers clamps
Title: Re: A Robinson from rejects.
Post by: Chipmaster on January 13, 2018, 08:55:19 PM
Clever stuff Jason. :ThumbsUp:

Andy
Title: Re: A Robinson from rejects.
Post by: Ian j on January 13, 2018, 09:19:47 PM
"That's looking nice Ian, good to see how parts can be made in different ways if we opt out of using castings"

It may take longer to machine a part from bar stock but  I think that out weighs the time taken in holding and positioning awkward shaped castings. Plus it's very satisfying turning "scrap" into machined engine parts.
Title: Re: A Robinson from rejects.
Post by: Jasonb on January 14, 2018, 07:29:12 AM


It may take longer to machine a part from bar stock but  I think that out weighs the time taken in holding and positioning awkward shaped castings. Plus it's very satisfying turning "scrap" into machined engine parts.

I was thinking just the same while making that gear, had I used the casting I would just have had to face off each side but the amount of work in cutting the gear from solid far out weighs that, gave me some new challenges and at the end of the day was 100 times more satisfyin.

My eccentric strap will be coming out of this disc that went into the scrap box with the "rod" from a bit of bar.

(http://img.photobucket.com/albums/v156/jasonballamy/Engineering/Otto%20Langen/DSC02015_zpscua8s8wj.jpg)

Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on January 14, 2018, 11:29:24 AM
You guys are amazing!

It just shows that with both time and patience the near impossible becomes reality.

Very well done.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Jasonb on January 14, 2018, 06:51:01 PM
I found that photo of how I locked the spindle on my X3 mill

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02463_zpsyrw6njtg.jpg)

So with the gear made I thought I may as well do the rest of the gearbox. The simple iron casting for this was one I was given by mistake so thought I may as well make use of it so cleaned up the spigots and turned to finished OD and finally parted off a 1/16" slice to form the cover.

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02442_zpsaftetwkl.jpg)

I opted for a different machining sequence to Graham and started by drilling and tapping the two holes and also spotted the position of the crankshaft hole with the two parts clamped together

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02464_zpsgwyt0ntg.jpg)

The remaining part was then turned down until the gear would just slip on with minimal play.

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02465_zpsivoiew6y.jpg)

The cover was then screwed on and the spot mark set to run true in the 4-jaw before drilling and then boring the hole to a running fit on the spigots either side of the spur gear.

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02466_zpsewphltgr.jpg)

With that done the cover was removed and the central boss opened up around the hole so the gear could slip inside

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02467_zpsjubkpsvp.jpg)

And this is how it fits together under the cover

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02468_zpshncqi0ul.jpg)

Works too :)

bKVMaQw4DVA
Title: Re: A Robinson from rejects.
Post by: RayW on January 16, 2018, 07:22:10 PM
While waiting for the new gears for my milling machine ( which arrived today), I have been getting on with the gearbox, which is now complete apart from the hole for the locating pin. Next job is the eccentric strap, but I am trying to decide how best to machine this casting, as it is a pretty awkward shape to hold. I am not sure whether to do it on the lathe in the four jaw chuck or on the milling machine with a boring head.I would be interested to hear what others have done.
I also made the little oil cups for the main bearing caps today.
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on January 16, 2018, 07:45:57 PM
Hi Ray.

Nice progress, that's the gearbox virtually finished.

As you remark the eccentric strap is an odd shape but all I used to do was hold it in the 3 jaw using a parallel behind it as a datum, gently remove parallel and proceed to bore out the casting to size. I never tried to bulk remove the metal but I wonder how a good quality hole saw might fare?

As a warning I had a couple that because of being a little heavy on the chuck key ended up 3 pointed, I learned to remove the bulk then slacken the grip on the last couple of light finishing cuts.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: RayW on January 19, 2018, 07:05:52 PM
Thanks for that advice Graham. I am pleased to say that the eccentric strap is now fully machined and assembled with the gearbox (see photos). Having taken the pictures, I have just realised that I have still not drilled the locating pin hole!
Title: Re: A Robinson from rejects.
Post by: crueby on January 19, 2018, 07:54:20 PM
That's quite a mechanism, very well done!
Title: Re: A Robinson from rejects.
Post by: Jasonb on January 21, 2018, 01:31:27 PM
Just like a Russian doll another part was stitch drilled out of the a disc of 10mm steel

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02469_zps87zre7oy.jpg)

Quick tap with a hammer and out drops the middle

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02470_zpscwiokbq4.jpg)

The rod and a block for the oiler were silver soldered on and job done. I will leave the pin hole and tappet untol I can assemble the engine to get the position/size correct

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02484_zpskjz9kln4.jpg)

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02485_zpsphyde41m.jpg)
Title: Re: A Robinson from rejects.
Post by: Ian j on January 21, 2018, 03:48:23 PM
Looking good Jason. I had difficulty holding the oiler block in position for silver soldering on mine, I had it clamped but that fell off when the blow torch heated it all up. I think if I had drilled it through to the eccentric and pinned it I would have a neater joint Still learning by my mistakes :)
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on January 21, 2018, 05:35:17 PM
Hi Jason.

Nice bit of fabrication!

Are they ď soft ď soldered? In fact I would approve as a ď good ď joint can be achieved without the necessity of using harder solders.

Ian, thereís an old saying.... the person that never made a mistake, never did anything.... The important thing is to learn from them, Iíve spent my whole life doing just that!

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Jasonb on January 21, 2018, 05:42:26 PM
Thanks Graham, They are silver soldered but there is a little JBWeld to tidy up the joint between rod & ring which may be the colour you are seeing. One of the problems with fabricating "on the fly" you don't always foresee the consequences of your actions.
Title: Re: A Robinson from rejects.
Post by: RayW on January 25, 2018, 04:24:27 PM
Finished the connecting rod today. When first assembled with the piston, I found that the end of the little end block was fouling on the unmachined area inside the piston. so ground away some of the excess metal with my trusty Dremel to give adequate clearance to allow full movement of the connecting rod.
I opted to press fit the little end bearing with Loctite 648 for extra security. This was rather than the pinch bolt arrangement as shown on the plans. As drawn, there is a small oil hole in the bronze bearing which is intended to line up with the slit in the block, but as I was not using that method of holding the bearing, I drilled a hole through the block and bearing to provide a method of getting oil to the bearing.
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on January 25, 2018, 05:31:03 PM
Hi Ray.

One less piece to make eh?   ;)

I used to hack them out of the solid, used to buy 6 foot lengths of BDMS bar. Go to use Alexís chop saw to make several big end caps and rod blanks. Then back home to the Harrison L 5 thatís fitted with a very handy taper turning attachment. Tedious but necessary when youíre building for a customer!

The pinch bolt was ď always ď dummied however.

Great progress, not much more to go!

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: RayW on January 26, 2018, 03:31:21 PM
Tackled a job today that I had not been looking forward to - line boring the main bearings. Don't know why I was so worried as it was a relatively straightforward process once I had the main engine casting clamped securely and positioned correctly on the milling machine table. I set it up first using my smallest centre drill as a guide, and without the bearing caps fitted, ensuring that my scribed centre line was exactly vertical and that the centre drill was in line with the mating face between the main casting and the bearing caps.
I then fitted the caps securely and centre drilled, then used progressively bigger drill bits until there was just a small amount left to remove with a reamer for the final fit.
Title: Re: A Robinson from rejects.
Post by: crueby on January 26, 2018, 03:36:23 PM
Nice! No matter how good the setup appears, it is always a nervous time to do that drilling.

 :ThumbsUp:
Title: Re: A Robinson from rejects.
Post by: Ian j on January 28, 2018, 12:24:58 PM
A bit more progress on my engine built from bar stock/scrap!
Exhaust valve chest:-
Milled/drilled/filed out of a lump of cast iron. I messed up the valve seat so ended up drilling out to 1/2" and turned  a bronze insert to be a close fit, drilled this 3/16" and 5/16" and formed the valve seat then pressed in with loctite. After about 30mins with grinding paste seem to have a good seal between the valve and valve seat.Silencer made from stainless steel , there's no baffles in it, was thinking of putting a piece of the steel type dish scourers.
Title: Re: A Robinson from rejects.
Post by: Jasonb on January 28, 2018, 01:33:25 PM
Thats looking good.

I'm hoping to get the reject of the rejects for this part and maybe a couple of others.
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on January 28, 2018, 03:08:19 PM
Thats looking good.

I'm hoping to get the reject of the rejects for this part and maybe a couple of others.

You shall Jason, you shall !

 :)
Title: Re: A Robinson from rejects.
Post by: RayW on January 28, 2018, 04:00:30 PM
I was making good progress with the inlet valve block until it came to drilling the 1/32" gas inlet hole. At my first attempt, the drill broke off in the hole after about 1/8" deep but fortunately, the broken part came out OK. I have since broken several more bits without progressing any further and I am at a loss to know what to try next.
I have been running the milling machine at its maximum of about 2000 rpm, but I suspect that I may need much higher speeds than that for such a small drill bit. I have also been using plenty of cutting oil.
I have a Dremel which runs at something like 30,000 rpm, but no way of holding it in a steady vertical position, and I am reluctant to invest in a special drill stand just for this one hole.
I would appreciate any advice as to the best way to proceed.

One thought I had was to drill out the hole to, say, 3mm to match the other holes, then fit a brass plug, which I feel would be easier to drill than the mild steel of the block.
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on January 28, 2018, 04:10:53 PM
Hi Ray.

What's the material you have used for the valve chest? I know its not a casting as I didn't have any of those.

My own thought is to try annealing the metal by a little heat and very slow cooling. Then try to re drill the hole.

A plug of Brass " press fitted " might be a suitable alternative.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Jasonb on January 28, 2018, 04:27:34 PM
Have you drilled the 1/16" hole yet as it may be catching as it breaks into that particularly if a bit out of line. Could try a bit of rod to fill the hole while you drill the small one.

I don't find the theoretical high speed is needed, I drill quite a lot of 1/32 Well 0.8mm split pin holes to retain pins and don't run the mill at it's max revs just somewhere near so maybe 1800rpm.

Maybe just a nasty bit of iron you have? Mine was from an old weight from a York multigym and quite nice to machine

J
Title: Re: A Robinson from rejects.
Post by: RayW on January 28, 2018, 04:39:28 PM
Thanks Graham and Jason. The block is mild steel and has been machining very nicely except for this hole. I am nowhere near deep enough to break into the 1/16" hole yet Jason. As I said, I had only managed to get about 1/8" deep before the bit broke.
I have been using some bits that came to me with a lot of other workshop tools and I am wondering now just how sharp they were.
I think I will order some new bits first to see if that solves the problem then look at other options like annealing or drilling out and plugging with brass. 
Title: Re: A Robinson from rejects.
Post by: Jo on January 28, 2018, 04:43:17 PM
I'm hoping to get the reject of the rejects for this part and maybe a couple of others.

It sounds like someone has given up on the idea of making his engine solely out of bar stock and is having to resort to more castings  :LittleDevil:


Ray - Yes you are drilling a "deep" hole (relative to the diameter of the drill) a good quality drill and careful pecking & cleaning out of the swarf will be called for. A sensitive drilling machine will also help  ;)

Jo
Title: Re: A Robinson from rejects.
Post by: Jasonb on January 28, 2018, 05:16:24 PM
Well as the first part I machined was the Cylinder casting it was never going to be an all barstock engine, then I went and found two other Robinson castings which sealed it's fate. Thought I would ask Graham if he had any flywheel castings and as he was making a trip to the post office what else may be knocking about in a dark damp corner of his shed, saves it all turning to iron oxide ;)

Having to wait a week or two for the castings forced me to start another engine, this one won't have any castings, not even the flywheel and at least I know there won't be any nasty holes hiding inside the parts :ThumbsUp:

I just used a 0.8mm bit from one of those cheap sets of 20 "micro drills" with all the sensitivity that a far eastern mill gives :LittleDevil:

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02443_zpsx62s1wy8.jpg)
Title: Re: A Robinson from rejects.
Post by: Jo on January 28, 2018, 06:42:51 PM
We know the truth you only pretend to not find castings desirable  ::)

I just used a 0.8mm bit from one of those cheap sets of 20 "micro drills" with all the sensitivity that a far eastern mill gives :LittleDevil:

Yes I also brought some of those Blue boxes of ex industrial micro drills from Tony at the Guildford show for £3 a box ;) He normally brings a few more along to each show if anyone else wants some.

Jo
Title: Re: A Robinson from rejects.
Post by: Jasonb on January 28, 2018, 06:49:06 PM
No these type of drill sets

(https://uk.brammer.biz/asset/small/40/8_/c6966bdc8580a50cca5a96c817af9813.png)
Title: Re: A Robinson from rejects.
Post by: RayW on February 01, 2018, 05:00:09 PM
Another milestone reached today with completion of the crankshaft. Last big job left to do now is to machine the flywheel casting, then it will be a matter of assembling all the various parts and checking for fit and alignment.
I still have the troublesome 1/32" gas inlet hole to drill, but I have received some new drill bits in the post which will hopefully do the job.
Title: Re: A Robinson from rejects.
Post by: Ian j on February 01, 2018, 05:36:13 PM
Looks good Ray. Is it fabricated or turned from one piece of flat bar stock ?
Ive just finished the inlet valve chest, I too was concerned about the 1/32" drill breaking so I opted to drill this first and then the 1/16" hole working on the theory that this was less likely to break on reaching the 1/32" hole . All went well . The only problem was I was thinking about this when marking out and machining the main part that it ended up narrower than shown on the drawing, but only we know that :)
 How are you and Jason making the valves, in one piece or silver soldering the valve and stem together, I've tapped the stem and fixed the valve with a small BA screw is this ok do you think?

Like you I have just the fly wheel to do on my Myford !!!
Ian
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on February 01, 2018, 06:15:17 PM
Good evening Ray and Ian.

My favourite casting to machine was always the flywheel, it came first every time.

Your crankshaft is looking good Ray, Silver soldered and pinned?

Ian, when you write ď fixed the valve ď are you suggesting that the stem is attached to the head with a small screw? I donít see a problem other than minute leakage without a suitable sealant.

I can understand the reluctance to machining one from the solid but back in the day engine valves were machined from forgingís, I know this to be true because I have several unmachined Barker ď B ď type valve forgingís in my workshop.

Iím beginning to get a little excited as the first run day is rapidly approaching!

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Ian j on February 01, 2018, 06:25:09 PM
Yes Graham the valve head is secured to the valve stem with a 7Ba screw.
As for getting it running I may be a coward and wait for Ray or Jason to sort out the plumbing for the gas :)
Ian

PS. Graham I only noticed today that you had written my engine number on the back of the name plate,thank you.
Title: Re: A Robinson from rejects.
Post by: Jasonb on February 01, 2018, 06:39:35 PM
I cut my inlet valve from a piece of 16mm Stainless and will also make the exhaust from solid.

Crank will be silver soldered and pinned, got to get a bit of 1/2" PGMS first though.
Title: Re: A Robinson from rejects.
Post by: RayW on February 01, 2018, 06:49:11 PM
I usually either make valves in one piece from stainless or silver solder a disc to a suitable sized stem, then machine head to shape while holding the stem in a collect.
The crank is silver soldered and pinned.
Title: Re: A Robinson from rejects.
Post by: RayW on February 05, 2018, 02:39:41 PM
Following a timely reminder from Graham about the problems of getting paint to stick to cast iron that has got impregnated with oil, I gave the base a protective first coat of acid etch primer today, after first wire brushing off most of Grahams special protective coating. I just hope that by doing so, I have not seriously devalued it by destroying the patina!
Seriously, though, Graham has a valid point. With cast iron being porous, it will soak up oil like a sponge and you will then have real problems when in comes to painting, so get some sort of protective coating on before the castings have a chance of being contaminated with oil or grease.

I will be doing more work in due course filling and rubbing down the castings and dealing with any flaws before giving them more primer and top coats.
Title: Re: A Robinson from rejects.
Post by: Jasonb on February 05, 2018, 03:28:23 PM
I've been quite tempted to make a model with a weathered look at some time, Grahams castings would give me a head start ;)

Not sure of I would go with the matt dusty barn fresh look or the wiped over with diesel wet look?

Here is an example of an Economy with the no bling look.

http://www.homemodelenginemachinist.com/showpost.php?p=162489&postcount=47

And a Galloway

http://www.homemodelenginemachinist.com/showpost.php?p=299205&postcount=70
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on February 05, 2018, 04:21:24 PM
Good afternoon everyone.

A few will know that my passion from late teens was the preservation of vintage machinery. My second engine was a half Ton Lister ď P ď type of 1919. This engine had been robbed of every last bit of Brass by the scavenging scrappers.

Its preservation back to near original condition meant a lot of parts had to be found, it never happened. The engine being so rare that I was forced into learning how to make patterns and then castings in my backyard. The rest is history....

As I grew older I realised that sometimes an engine looked better in the ď as found ď condition, in fact they sold better as a prospective buyer wanted to do the restoration themselves. A friend of mine used to create the as found look regularly by sullying the paint with old engine oil!

Itís a fact that these full size engines were bought to do work and their condition reflects it.

Attached is a picture of my unrestored Robinson type " XP " the " P " suffix is for Petrol, a very rare engine that was converted to Gas as the special inlet and carburettor were missing. The crank guard doubled as the Magneto bracket.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: RayW on February 05, 2018, 04:55:41 PM
I like the finish on the Economy model, but the Galloway looks a bit too "patchwork quilt" to be realistic.
I have always restored engines to show condition but can also see the attraction of leaving them in their working clothes. A dear late friend of mine was very much of the "conserve" rather than "restore" brigade and we had many amusing discussions on the subject. The irony was that he bought a beautifully restored Petter Handyman as a present for his wife and it lived for many years on display in their sitting room without ever being run.

As regards the Robinson, I suppose the correct authentic finish should include a wipe over with a rag soaked in chip fat!
Title: Re: A Robinson from rejects.
Post by: Jasonb on February 05, 2018, 05:12:19 PM
As regards the Robinson, I suppose the correct authentic finish should include a wipe over with a rag soaked in chip fat!

It would give it that authentic Chippy smell ;)
Title: Re: A Robinson from rejects.
Post by: Ian j on February 07, 2018, 01:17:23 PM
A bit more progress on my engine built from bar stock/scrap!/casting

Flywheel ('s):-

The gap on my Myford ML7RB only allows 1 1/2" width in it so I  bolted the flywheel to the table of the milling machine and milled a little off the face of one of the bosses and the face of the rim on the other side this allowed it to fit in the gap and finish just under the 1 1/2" total thickness.
The flywheel on the left is yours Graham and the one on the engine is the one I had cast using yours as the pattern.Key way was cut using my home constructed slotter, just takes a few minutes.
Also remade the valves , turned from SS bar as advised earlier.
Title: Re: A Robinson from rejects.
Post by: crueby on February 07, 2018, 03:07:20 PM
Thats looking great! That flywheel fits the style very nicely.
Title: Re: A Robinson from rejects.
Post by: RayW on February 07, 2018, 03:28:07 PM
Looking really good Ian. I still have the flywheel to do. Is the keyway in the flywheel parallel or tapered?

Ray
Title: Re: A Robinson from rejects.
Post by: Ian j on February 07, 2018, 04:56:56 PM
Ray. The drawing shows the key way to be 1 in 100 taper ( written on the right hand side just above the 1/2" diam bore dimension on the fly wheel drawing.)
 The weight of the flywheel certainly sorts out any tight spots on the engine :)
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on February 07, 2018, 05:07:12 PM

 The weight of the flywheel certainly sorts out any tight spots on the engine :)


Hi Ian.

Very nice! The full scale flywheel weighs over 80 Lbs believe it or not. So you had another made from mine eh? Cunning!!  ;)

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on February 07, 2018, 07:10:17 PM
A good apprentice anticipates his bosses needs....

I felt that an introduction to the gas plumbing might be useful at this juncture.

I have attached a picture of my Robinson number 103.

As most will know the original engines ran on " Town gas " lighter than air with a much larger volume needed than what we're going to use with Propane. I learned a little over the years....  ;)

With town gas the mixture for combustion can be very wide but Propane isn't so forgiving it's quite a narrow window.

These engines employ " hot tube " ignition, this means an externally heated hollow tube sealed at one end with the other open to the combustion chamber. In the old days using town gas the tube didn't need to be ridiculously hot so a simple low pressure gas air mixer made a flame that surrounded the ignition tube.

We discovered very early that for the Propane air mix a bright Orange tube was essential to successful ignition. Back in the day Primus were offering a range of beautifully made burners, we opted for the 8842 because it produced a neat pencil point flame. The downside is that they need around 40 PSI of gas pressure to work effectively.

The dilemma is.... Do we have two gas lines to the engine, one low one high pressure? My answer was no!

My solution.... In the picture you can see a " Wade " 3/16" needle valve directly screwed into the inlet valve, there's a good reason for this. A scale engine suffers with a " little does a lot " a tiny tweak of gas makes a huge difference wheras the full size wouldn't notice it so much. What you can't see is that the Copper pipe bringing the gas into the needle valve has had the end plugged with soft solder and then punctured with a fine needle. This doesn't alter the pressure but drastically reduces the flow so there's more control.

I seem to have gone on a bit but if you need more information please don't hesitate to ask, I earned that Tee shirt the hard way!

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Jasonb on February 07, 2018, 07:59:21 PM
Thank's for that graham

Do you use a low pressure regulator on the propane cylinder? Also is there any form of demand valve, I would have thought not as the inlet valve acts much like a demand valve only opening when there is a vacuum in the cylinder.

J
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on February 07, 2018, 08:42:32 PM
Thank's for that graham

Do you use a low pressure regulator on the propane cylinder? Also is there any form of demand valve, I would have thought not as the inlet valve acts much like a demand valve only opening when there is a vacuum in the cylinder.

J

Hi Jason.

No, my Robinson runs at 40 PSI from an adjustable HP bottle regulator. Not on demand.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Ian j on February 07, 2018, 10:41:42 PM
so the pipe going up to the T comes from the regulator on the gas bottle?
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on February 08, 2018, 10:49:38 AM
so the pipe going up to the T comes from the regulator on the gas bottle?

Good morning Ian.

Yes it does.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Jasonb on February 08, 2018, 11:21:50 AM
Thank's Graham, standard torch type regulator it is then and not one of the flat LP ones.

Just need some castings now ;) But I found something to do while I'm waiting

(http://img.photobucket.com/albums/v156/jasonballamy/Engineering/Vertical%2024/DSC02557_zpsd21vxsam.jpg)
Title: Re: A Robinson from rejects.
Post by: Ian j on February 09, 2018, 08:59:46 AM
Just a thought, Ray & Jason what are you plans on providing lubrication to the big end on the crank shaft, the drawing's show one method.
Have you drilled that 1/32" hole yet Ray?
Title: Re: A Robinson from rejects.
Post by: Jasonb on February 09, 2018, 10:46:45 AM
I think the greaser that is suggested on the drawings is correct, you can see it on this full size engine. Anyone for a scratch built chipper?

(http://beamishtransportonline.co.uk/wp-content/uploads/blogger/--we2pI6U3v4/TWYoj0EADuI/AAAAAAAAD3w/Ml7v3NDJyTg/s1600/DSC07536.JPG)

(http://beamishtransportonline.co.uk/wp-content/uploads/blogger/-epFpf9egaYY/TWYojiu0PfI/AAAAAAAAD3o/Vmw8akNZgSE/s1600/DSC07535.JPG)

Or what about a peeler?

(http://beamishtransportonline.co.uk/wp-content/uploads/blogger/-7b26IPP20HI/TWfU43iDExI/AAAAAAAAD54/YzhvdKyI2dE/s1600/Robinson%2BAdvert.jpg)
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on February 09, 2018, 11:13:51 AM
Good morning Jason.

How wonderful!

The pictures posted above are of the full size Robinson ď X ď type that youíre all making models of.

The engine belonged to Geoffís wife and was loaned to me back in 1989 for both scaling and getting going. I took it to a local rally and got a mention in the paper as it was the oldest exhibit there.

Re. Lubrication. I would recommend an MS grease because the properties of Molybdenum Disulphides are well known and understood.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Jasonb on February 09, 2018, 11:20:17 AM
Graham, (and other builders) I got those photos from the following, there may be some more updates on it's progress.

http://beamishtransportonline.co.uk/2011/02/potato-chipper-for-chip-shop-a-tongue-twister/

http://beamishtransportonline.co.uk/2011/02/chip-shop-chipper-update/
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on February 09, 2018, 11:40:44 AM
Hi Jason.

As far as Iím aware the ď Chip shop ď project at Beamish was/is on hold, sad really.

However your links might give an idea for paint colour..... ď Manchester Red ď

As a side note I wonder if their statement about the period advertising is correct? The engine in that picture has the epicyclic gearbox which was patented in 1894 and superseded by the more conventional two spur gears soon after.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Jasonb on February 09, 2018, 01:29:59 PM
Well it's no secret that I do like a red engine :) Just had a look at teh manchester red which is not as bright as you see quite a few of these engiens painted in

http://www.craftmasterpaints.co.uk/colours/standard-range

I was thinking of using teh same red that I did on my Tidman and that looks reasonably close.

(http://img.photobucket.com/albums/v156/jasonballamy/Engineering/Tidman%20Organ%20Engine/DSC00571_zpsxawkh9wc.jpg)
Title: Re: A Robinson from rejects.
Post by: RayW on February 10, 2018, 04:21:07 PM
Hi all. Have been thinking about making a miniature spring loaded, or screw down, greaser to fit onto the big end cap, but need to check how much clearance there is when the crank revolves. If there is sufficient room, I would prefer to do it that way rather than drilling through the web and, therefore, through the web pins.
Title: Re: A Robinson from rejects.
Post by: Jasonb on February 10, 2018, 04:30:56 PM
I've just come in while the crank cools from soldering, Drilled and tapped the axial hole before soldering and will off set that pin so it just nicks the side of the pin rather than drilling across the middle.

As the base casting is notched out to clear the big end fixings I can't see there being much room but can't tell until I have the casting
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on February 10, 2018, 05:21:06 PM
Hi Both.

I've never pinned a Silver soldered crankshaft ever, not had a single one break either!

Attached are a couple of photographs of 103 showing how little clearance there is to play with and my alternative big end greaser.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on February 10, 2018, 06:07:25 PM
I'd also like to share....

Don't forget to tighten your gudgeon pin screws!!

Look closely at the pool of oil at the bottom, no wonder they smoke.

Cheers Graham.

PS. When my cameraman gets a day off from work I'll do a short video of how easy they are to start and run.
Title: Re: A Robinson from rejects.
Post by: Jasonb on February 11, 2018, 05:31:21 PM
Soldered up the crank and then gave it a quick clean up followed by drilling 1/16" for the pins. Loctited them into place and left to set overnight.

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02569_zpsufifwkm0.jpg)

Peined them over and then filed flush followed by cutting the waste out of teh middle of the webs and cleaning everything up.

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02571_zpsytxc5ane.jpg)
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on February 12, 2018, 06:19:52 PM
Good evening all.

As promised....

xnL8h1em45o
Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Jasonb on February 12, 2018, 06:41:32 PM
Thanks for that Graham.
Title: Re: A Robinson from rejects.
Post by: Chipmaster on February 15, 2018, 01:49:33 PM
Robinson base minutes after grit blasting treatment. This is the first time I've used a shot blasting firm, they blasted three castings while I waited for about ten minutes and I gave the man £10.
A coat of primer is drying while I add these pictures to this thread.

(https://farm5.staticflickr.com/4671/40236491502_6b43028a32_z.jpg) (https://flic.kr/p/24iyx77)Robinson X Type (https://flic.kr/p/24iyx77) by Andy (https://www.flickr.com/photos/116764188@N08/), on Flickr

(https://farm5.staticflickr.com/4768/38471141520_0cb87f77d8_z.jpg) (https://flic.kr/p/21ByE4s)Robinson X Type (https://flic.kr/p/21ByE4s) by Andy (https://www.flickr.com/photos/116764188@N08/), on Flickr

(https://farm5.staticflickr.com/4746/25410164357_3e17ddcef2_z.jpg) (https://flic.kr/p/EHpJA2)Robinson X Type (https://flic.kr/p/EHpJA2) by Andy (https://www.flickr.com/photos/116764188@N08/), on Flickr

(https://farm5.staticflickr.com/4768/38471141520_0cb87f77d8_z.jpg) (https://flic.kr/p/21ByE4s)Robinson X Type (https://flic.kr/p/21ByE4s) by Andy (https://www.flickr.com/photos/116764188@N08/), on Flickr

Plus two dynamo castings
(https://farm5.staticflickr.com/4632/40236772302_f716b08962_z.jpg) (https://flic.kr/p/24izYzu)P1070360 (https://flic.kr/p/24izYzu) by Andy (https://www.flickr.com/photos/116764188@N08/), on Flickr
(https://farm5.staticflickr.com/4676/39384363955_f1d2febd21_z.jpg) (https://flic.kr/p/231gagR)P1070361 (https://flic.kr/p/231gagR) by Andy (https://www.flickr.com/photos/116764188@N08/), on Flickr

Andy
Title: Re: A Robinson from rejects.
Post by: Jasonb on February 15, 2018, 02:53:47 PM
Now that is what castings should look like none of that iffy coating :LittleDevil:, funny enough I was looking to see how could do it for me locally only last night as some rust is on it's way to me.

Do you have the before pictures?
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on February 15, 2018, 04:29:56 PM
Hi Jason.

Cheeky, as ever!  :)

Youíll be able to post some pictures of your own in the near future!

Andy.

Thatís just the way they used to leave us however Buckleyís finish had more of a shine because they used Iron shot in their blasters.

Nice to see Vincentís Manchester dynamo base again.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: RayW on February 15, 2018, 07:16:01 PM
Hi all,

Still making progress and it's really beginning to look like an engine (minus one big round thing!). Assembled all the components loosely today to ensure that everything lined up correctly and turned properly. Just needed to open out the guide hole in the end of the eccentric arm a bit to stop it binding, but otherwise all was good.

On a not quite so successful note, I spent a lot of time making four nice piston rings today, then managed to break all four trying to get them on to the piston. I was trying to open out the rings sufficiently to go over the end of the piston but then remembered, when it was too late, that the best way is to get one end of the ring in the groove first, then progressively work the rest of the ring down. If anyone has any alternative techniques, I would be interested to hear.

Ray

 
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on February 15, 2018, 08:16:30 PM
Hi Ray.

Yes, fitting rings can be a tricky business. I wonder, were they properly annealed ?

I always use the method of opening the ring carefully by placing the edge furthest from the split partially onto the piston edge and then working my way towards the ends. It's not infallible though, I've still broken a few !!

Getting the rings to a bright Orange quickly then allowing a slow cool is my method of annealing them.

Having tried " Viton " in my Gardner I would recommend them over the split cast Iron rings any day !!

Cheers Graham. 
Title: Re: A Robinson from rejects.
Post by: Chipmaster on February 15, 2018, 08:51:45 PM
Now that is what castings should look like none of that iffy coating :LittleDevil:, funny enough I was looking to see how could do it for me locally only last night as some rust is on it's way to me.

Do you have the before pictures?

Here are the 'before' pictures taken by Graham

(https://farm5.staticflickr.com/4760/26415436408_9547eb9ff7_b.jpg) (https://flic.kr/p/Gff1WL)Castings 1 small (https://flic.kr/p/Gff1WL) by Andy (https://www.flickr.com/photos/116764188@N08/), on Flickr
(https://farm5.staticflickr.com/4708/26415436118_fbb3669318_z.jpg) (https://flic.kr/p/Gff1RL)Castings 3 small (https://flic.kr/p/Gff1RL) by Andy (https://www.flickr.com/photos/116764188@N08/), on Flickr
(https://farm5.staticflickr.com/4769/39576447034_6aafe05dd3_z.jpg) (https://flic.kr/p/23ieCT5)Retlas dynamo base before blast cleaning. (https://flic.kr/p/23ieCT5) by Andy (https://www.flickr.com/photos/116764188@N08/), on Flickr

Andy
Title: Re: A Robinson from rejects.
Post by: Jasonb on February 15, 2018, 08:55:16 PM
That worked well then and saves a lot of elbow grease
Title: Re: A Robinson from rejects.
Post by: Jo on February 15, 2018, 09:10:20 PM
Two sets of Castings  :o I thought it was only me and my supplier who got TWO sets of castings between us, Graham  :stickpoke:

Those castings look so familiar   :noidea:

Jo

P.S. They also have the "slipper view"  ::)
Title: Re: A Robinson from rejects.
Post by: Chipmaster on February 15, 2018, 09:36:23 PM
Yes you've worked it out Jo, it was the slippers wasn't it :praise2:. I had to copy them from one of your posts as I didn't take any 'before' pics myself   :cheers:. All our castings were in the same state.

I recommend using shot blasters, I would have saved a lot of effort if I had used the shot blasting firm on my earlier engine castings.

Andy
Title: Re: A Robinson from rejects.
Post by: RayW on February 16, 2018, 10:28:17 AM
Like Graham, I had considered using viton o-rings as piston rings, but not sure how I would do this as the grooves in the piston are not square as would be needed for circular section rings. The grooves are 80 thou wide and 93 thou deep so would require either oval or rectangular section rings, which do not seem to be easily available. I will persist with cast iron rings for now and just make plenty of spares!
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on February 16, 2018, 11:21:11 AM
Hi Ray.

You donít need to worry about the section of the groove, itís the width that counts. I have directly substituted round rings into the square grooves on my Gardner piston.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Jasonb on February 16, 2018, 01:26:19 PM
Postie has been and dropped of a Burner, the "10mm" Sievert is 11mm OD and easier to get hold of, mine came from Hamilton Gas.

For a nominal 3/32" section O ring the best fit will be if the depth can be increased to 0.094" and width upto 0.125"
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on February 16, 2018, 01:56:32 PM
Hi Jason.

Your parcel of goodies is on its way, should land on Tuesday.

Itís looking like March will see the appearance of 3 Robinsonís, very nice!

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Jasonb on February 16, 2018, 03:51:00 PM
Thank you Sir, looking forward to it.

Progress may be slowed a little as it's the time of year to think about repotting my Bonsai and I did not do many last year so plenty to do this time around.
Title: Re: A Robinson from rejects.
Post by: RayW on February 16, 2018, 07:51:24 PM
Thanks Graham and Jason for the o-ring advice. I had assumed that the rings needed to seat on the bottom of the groove to ensure that the outside of the ring was held in contact with the cylinder wall. I have now made new cast iron rings and installed them on the piston relatively easily by locating one end of the ring into the groove, then gradually feeding the rest of the ring into the groove in a sort of spiral action until just the second end is left to slip down and into the groove.

One ring is a nice snug fit widthways in its groove, but the other is a bit too narrow, but I am wondering if this will matter as there is really strong compression and suction anyway. The piston is quite a tight fit in the cylinder at the minute, although it does move up and down with a bit of a push. I am not sure whether to leave it as it is and let it bed in with plenty of oil when running, or whether to hone the cylinder a bit more to give slightly freer movement, but at the risk of losing a bit of compression when fully bedded in.
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on February 16, 2018, 08:01:32 PM
Hi Ray.

An emphatic " leave it alone " from here....

Once that heavy flywheel is fitted and turned a few times things will " bed " !!

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: RayW on February 16, 2018, 08:49:27 PM
Thanks Graham. That was what I thought. Next job is to machine the flywheel.

Ray

P.S. Yes, I did eventually drill the 1/32" gas hole. The problem why I kept breaking so many drill bits was that a tiny piece of the hard tip of the first bit that broke must have been left in the hole. Consequently, the other bits broke when they hit it. I eventually drilled a 3mm hole through from the other side then made a brass jet for the inside and a steel blanking plug for the outside so that that hole cannot be seen.
Title: Re: A Robinson from rejects.
Post by: RayW on February 17, 2018, 04:03:15 PM
Completed machining of the flywheel today, apart from cutting the keyway, which will have to be done on the lathe as I do not own any broaches or an arbor press. I followed Graham's advice and opened out the bore with a small boring tool prior to finishing with a reamer. The result is a nice snug fit on the crankshaft and, hopefully, no wobble!

P.S. A handy hint  - don't stick your thumb on a grinding wheel while it is running. I did today while grinding a boring tool and it really hurts. Net result is a groove right through my thumbnail and deep into the end of my thumb.



Title: Re: A Robinson from rejects.
Post by: Roger B on February 17, 2018, 04:50:18 PM
The engine is looking good  :praise2: The thumb not so good  :(
Title: Re: A Robinson from rejects.
Post by: Kim on February 17, 2018, 05:18:11 PM
P.S. A handy hint  - don't stick your thumb on a grinding wheel while it is running. I did today while grinding a boring tool and it really hurts. Net result is a groove right through my thumbnail and deep into the end of my thumb.

Yes!  Excellent hint, Ray! I did that many years ago when I was working my way through school, working in a small machine shop.  Made a deep divot in my thumb nail and my thumb.  Still have a slightly odd shaped thumb nail which I blame on that incident!

Hope your thumb heals quickly!  Ouch!

The engine is looking great too!  I have been following along enjoying your build.
Kim

Title: Re: A Robinson from rejects.
Post by: RayW on February 19, 2018, 07:40:37 PM
After toying with various ideas I got round to sorting out the big end lubricator today. Came up with the solution shown in the photos. Basically, it is an internally threaded tube with a small threaded plunger which, when screwed down, forces the grease through a series of interconnected holes ( as shown on the plans), exiting through a hole in the main journal. With all the holes filled, just a couple of turns on the plunger produces a nice "worm" of grease at the journal.
As can be seen, clearance is pretty tight - maximum length for the greaser body is 10mm.

Ray
Title: Re: A Robinson from rejects.
Post by: Ian j on February 19, 2018, 08:15:33 PM
Ray,
Great minds think alike!
This is my solution as I didn't fancy drilling the crankshaft after it was assembled. On my fabricated base there  a little more clearance.The oiler/greaser is as yours.
Title: Re: A Robinson from rejects.
Post by: RayW on February 19, 2018, 08:55:53 PM
Snap!! I must admit that I was a bit apprehensive about drilling the crank after it had been made, but it proved quite straightforward. Like you, my initial thought had been to fit the greaser into the big end cap, but as the cap is quite thin already in the centre, I was worried about weakening it too much by drilling and tapping for a 2BA thread.

The main job left to do now is the keyway in the flywheel, a job I am not particularly looking forward to as the only way I have of cutting the keyway is on the lathe, which is not ideal.
Title: Re: A Robinson from rejects.
Post by: Ian j on February 19, 2018, 09:37:11 PM
"he main job left to do now is the keyway in the flywheel, a job I am not particularly looking forward to as the only way I have of cutting the keyway is on the lathe, which is not ideal. "

I built this slotting attachment:-

http://www.homemodelenginemachinist.com/showthread.php?t=4366&highlight=lathe+slotting+attachment

No plans, just from the photo's. Main part milled from a lump of ali. ( sounds familiar :) ) works very well----I don't cut that many keyways.
Title: Re: A Robinson from rejects.
Post by: RayW on February 19, 2018, 10:41:56 PM
Thanks Ian. Just had a look at that link and how spooky is that - my initials are RSW! Now I feel I ought to have a go at making it.
Title: Re: A Robinson from rejects.
Post by: Jasonb on February 20, 2018, 07:34:58 AM
I never had a problem doing keyways in the lathe by using the carrage before I bought some broaches. CI is quite easy to do, steel takes a bit more effort but can still be done - these four are 3/16" wide and 1" long in steel

(http://img.photobucket.com/albums/v156/jasonballamy/Fowler%20A7/A7-2ndShaftGears.jpg)
Title: Re: A Robinson from rejects.
Post by: Ian j on February 20, 2018, 05:05:46 PM
Today working on the gas plumbing. The needle valves I had looked a bit industrial to mount as yours Graham plus they were female, So I went for a similair method used on the red engine shown in an earlier video ( this was the one I saw running at the Anson museum) Just need to set the timing and see what happens !!

PS Tried the hot tube burner and that's OK. In your video Graham is that in real time from lighting the burner and getting the engine to run ie just a few minutes to get the ignition tube hot enough?
Title: Re: A Robinson from rejects.
Post by: RayW on February 20, 2018, 06:48:12 PM
Looking very good Ian. We will expect the video of the first run any day soon.

Ray
Title: Re: A Robinson from rejects.
Post by: Jasonb on February 21, 2018, 07:46:13 AM
With a suitably antiqued base casting now sitting in the workshop I had  acloser look at the base drawing. Is it correct that the ctr line of the cylinder does not pass through the ctr line of the crankshaft? I have done other engines where the two are offset as per the original engine such as the Baker Monitors but just wanted to check before cutting metal.

Sketch below shows 1.5" for the vertical face from the top of the slope and then 0.625 in to the crank ctr line. The green line is 1.093 above the sloping face.

Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on February 21, 2018, 11:19:08 AM
Good morning All.

Yesterday was a long and both sad and happy day, glad to be home.

For Ian, yes that was a ď cold start ď we use a thin wall to the Stainless Steel ignition tube and those little burners are very effective. You get a nice little Orange spot formed on the side.

Please be aware that the flame point has a direct relation to ignition timing, lower down, advanced higher up retarded.

For Jason, I hadnít noticed that, to be honest! We just machined and then fitted the parts together, it worked! Drew them afterwards....  My advice would be to assemble and see how it works.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: ettingtonliam on February 21, 2018, 08:15:25 PM
Graham
Not strictly from rejects, but definitely Robinson related. A few weeks ago I managed to acquire an unmolested set of castings for the Robinson hot air engine, still I think, in the original packaging. There is one drawing, is that all? I don't quite understand how the displacer piston goes together, what material did you use. I was thinking of thin wall brass tube with sheet brass end pieces, made to be a slack (maybe 30 thou) fit in the hot end cylinder. How hot does that get? Can I use soft solder on that displacer piston?
The other bit I don't understand is what seems to be a governor valve in the end of the cold cylinder. How does that work?

Regards

Richard
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on February 21, 2018, 08:35:18 PM
Hello Richard.

Welcome to MEM.   :ThumbsUp:

This thread might be a good place to look for your answers.   ;)

I'll copy, paste and answer there.

http://www.modelenginemaker.com/index.php/topic,7561.0.html

Cheers Graham.

Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on February 22, 2018, 04:48:15 PM
Robinson mania....

Having effectively ruined my " rejects " thread by letting go of all the castings I had we had to resort to a new one!

Milling the " water base " is a doddle with a big machine.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Jasonb on February 22, 2018, 05:05:55 PM
Looks better than the original rejects and unlike mine I doubt you had any sparks flying while trying to machine the iron, 'twas a bit hard!
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on February 22, 2018, 05:12:49 PM
Hi Jason.

Iím really quite shocked....

That base was ď run short ď not quite enough metal to finish the pour properly. I suppose it might have suffered a chill?

Rhuddlan Iron was always a bit tougher than Buckley but I never saw sparks other than when grinding.

Photos soon?

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Jo on February 22, 2018, 05:41:12 PM
Photos soon?

He's hoping that most people don't read what he writes so the longer he does not show any pictures of castings the longer he can pretend he doesn't like working with them  ::)

Jo
Title: Re: A Robinson from rejects.
Post by: Jasonb on February 22, 2018, 06:45:23 PM
Just pacing myself Jo but just for you.

Think I may ask for some money back as the flywheel did not come with that special coating that I had been looking forward to though I did get a couple of sink holes on the other side thrown in for free.

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02598_zpsndqmvzts.jpg)

Base casting only had minimal surface rust but one of the bent hails did come out while doing the initial fettling so will have to plug the hole if I want to avoid a wet patch.

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02597_zpsfslj7qui.jpg)

It just so happens that Lidl had their small sand blast guns in the specials this week so thought it was worth a punt for the small outlay, just gave it a very quick try out on the cast writing and it seems to work quite well if a little messy.

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/20180222_174645_zpso10m6c8d.jpg)

I started by shimming up the casting to get it to sit as evenly as possible and took a skim off the top which saw the first sparks start to fly, the dark shiny areas are the hard bits.

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02599_zpsdufphwjp.jpg)

With enough flat area to get a good mounting I turned the casting over to do the feet, again rather hard.

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02599_zpsdufphwjp.jpg)

With that done I put it back up the right way and took a couple more passes with some new tips in the cutter as the hard spots had taken the edge right off them and got a reasonable finish on the top. (no pic yet)

J

Title: Re: A Robinson from rejects.
Post by: Jo on February 22, 2018, 07:17:08 PM
Just pacing myself Jo but just for you.

They have been in his hands for less than 48 hours and the swarf is already flying  :lolb:

What happened to the casting fondling  :facepalm:

Jo
Title: Re: A Robinson from rejects.
Post by: Jasonb on February 22, 2018, 07:24:18 PM

What happened to the casting fondling  :facepalm:


I'll leave that to the girlies :LittleDevil:
Title: Re: A Robinson from rejects.
Post by: Ian j on February 23, 2018, 04:02:46 PM
OK a cry for help.
First test run a BIG disappointment.After letting the ignition tube get hot for several minutes turning the low pressure gas valve a small amount and spinning the fly wheel I can see the inlet valve flicker open a tiny amount but there's no attempt to ignite the gas which I hear if I hold the valve open. I think I set the exhaust valve timing as in the build instructions but on the intake stroke the exhaust valve is open only closing just before BDC.
If I remove the exhaust and inlet valve chests I can feel compression with a finger over the ports, I ground in the inlet valve which seems a good seal.The ignition tube is drilled out with a No. 11 drill, the low pressure valve inlet is via a No. 60 drill.  :(
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on February 23, 2018, 04:49:17 PM
Hi Ian.

Not to worry, this IS the 21st century after all.

Do you have Skype? We could work through this together.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Ian j on February 23, 2018, 05:35:30 PM
Thank's for that Graham.
I have skype but never used it, I would have to get up to speed with it or we would get side tracked sorting skype out :)
I'm getting gas into the cylinder because I can ignite it at the exhaust  port on the exhaust stroke. When would you expect the exhaust valve to be shut on the intake stroke?
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on February 23, 2018, 05:47:20 PM
Hi Ian.

Iíve been using Skype for years it works really well particularly if you have a hand held device like a phone or tablet.

Iíll PM my ID to you.

The exhaust can start opening anytime after 20 past the hour but must close at TDC, thatís the important part.

A simple test can be done by lighting the seepage past the inlet valve if you get a Yellow flame higher than say 2 inches, way too much gas is available. Youíre looking for about an inch with everything stationary.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: fidlstyks on February 24, 2018, 05:32:00 PM
Jason , I know you have machined lots of  castings so I should not tell you what to do. So I just say what i do once I hit hard spots I put my castings in a coal forge and turn them orange. The thicker  the longer but some times just a quick orange does it. A chill Iis easy to take out .
   But other problems can exist.  I have melted some 25 tons of cast iron since the 80s which produced some 18-20 tons of castings. I know what makes hard spots. One mistake was using a Chrysler interceinterceptor block for iron.  They  have nickel in them.  So do Pontiacs. Very hard, it made nice ringing bells though. I like small  block  Chevy's. So soft you can scrape it away with a pocket knife.
Using a  carbon bonded crucible is very bad. Use only clay graphite crucible if melting in a crucible. I also stir in carbon and silicon carbide inoculate and Ferro silicon. What exactly they are made of I do not recall. It's stuff I buy at the local foundry.
  My experience with a slick shinny spot is that it is carbide . Black pepper spots are silicon. Both bet bad news but will melt or burn out in a forge. I like to test all iron before shipping and would never ship any bad iron. I throw it in the scrap iron or burry it. Maybe happened on 4 pots over the years.
    I think those wide shinny spots look like carbide to me. But pictures can be deceiving on the internet. If the grey areas are the hard spots look for black pepper spots.  Silicon in excess makes such pepper spots.
  In the large foundry they take a 1 " square grind it perfectly flat on a surface grinder, place a drop of Nitric Acid on it and hold it to a chart of 1" squares that looks like the solar system. You then find a square picture that matches your piece with small pepper spots counted,  half moons and other shapes. And there it has numbers that tell you what your iron is made up of.
 The books I have say mchinable iron is 1.75-2.5 % silicon. If you see the iron like this with many spots it may be 7.5 %.
Maleble iron is 7.5% and cast as white hard iron. Then malableized by heating orange or about a week. Not made much now days. Ductile rules. It also gets hard again if your cutter gets dull and heats it up. Then your done. That or heat it for a week again.
   Just thought some one might be interested as you chaps seam to be all befuddled by hard spots.
Title: Re: A Robinson from rejects.
Post by: Jasonb on February 24, 2018, 06:40:04 PM
Thanks, I have used the heat method many times myself and was getting close to heating this one but don't really have the equipment to get it all upto temperature and did not want to risk local heating on what was already a flawed casting.

I should stress that right from the start I knew this was a reject casting and probably one of the worse ones that graham had, if it had been one that was upto his usual standard that went out to customers there would have been no issues with it.

I don't think the hard areas are any specific metal inclusions just typical chilled castings where the thin section has cooled too quickly, a lot of the edges on this casting are 1/8" or less and there was also a lot of flash where iron had worked its way around the core prints which left a lot of thin metal. Most of the hard stuff was not too deep so I was able to get back to a reasonable metal in most places.

Pics of todays machining to follow
Title: Re: A Robinson from rejects.
Post by: fidlstyks on February 24, 2018, 07:33:51 PM
That's good news. I always grind on thin spots before machining. The chops from that will ruin a lathe or mill.
I local heat with a torch lot. Easy fix. Too bad his foundry closed up on him.
Title: Re: A Robinson from rejects.
Post by: Jasonb on February 24, 2018, 08:50:49 PM
I posted the wrong photo at the end of the previous update, this should have been the one showing the feet being machined.

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02600_zps2hf8d4pv.jpg)

The next job was to clock in my machining plate on the mill and to get the casting sitting as true as possible averaging out any undulations in the surface. Once happy with that the holes in the feet were transfered to the plate and tapped for screws. I then skimmed the vertical face at the top of the slope and clocked that in before setting back 5/8" and zeroing the DRO on the crank ctr line, used an edge finder to locate ctr in the y axis too and then drilled the stud holes for the bearing caps.

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02603_zps1jbxy9hh.jpg)

In this close up you can see the surface has improved with just a few darker hard areas showingparticularly around the far bearing area.

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02604_zps2wbr4g0j.jpg)

I can now see why Jo likes having more than one of all machines as when you forget to machine the bearing caps before hand  it is easy to pop over to another machine to do them. These were much nicer to machine and the SX2.7 romped through them with a cheap 10mm rougher.

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02602_zpstmtbnbx8.jpg)

I tried with the rougher to do the inside faces of the bearings but just took the edge off it as soon as I got to the lower half so had to revert to the carbide insert little hogger which luckily has a 1" diameter cut as my carbide end mills were not long enough, again you can see the more polished hard areas in the top corners of the lower halves

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02607_zpsiobyu3nx.jpg)

Having the casting on the machining plate made it easy to hold and clock in to machine the angled face that the cylinder mounts to.

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02608_zpsgketn620.jpg)

Once through the surface it was not too bad to machine and helped by another fresh corner of the inserts which had blunted again by now.

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02609_zpsqzrc4vyi.jpg)

Again the plate made it easy to set up to bore the bearings. With teh caps being a nice soft iron and the lower half somewhat harder I could see the drill starting to deflect into the softer stuff so stopped early and changed to a carbide tipped bar in the boring head. Not 100% happy with the fit of finish of teh holes but will probably do for the little running this engine is likely to do but could squeeze in some thing walled bearing shells if needed, I kept the cap bolts a bit further apart than drawing to allow a bit more room for this if need be.

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02610_zpsd8qqtqkb.jpg)

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02611_zpsq84fymmu.jpg)

And a group shot to finish off with the crank and cylinder in place.

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02612_zpsryvlaamj.jpg)

Flywheel has been fettled and seems soft :) and the faceplate is on the lathe ready for some turning tomorrow, got to get these castings out the way and into a finished engine ASAP, can't see the point of having them to fondle. There is also a risk that the Welsh Gold coating may be catching :-[

Title: Re: A Robinson from rejects.
Post by: RayW on February 25, 2018, 04:30:58 PM
I too have been "fettling my flywheel" Jason! Having removed the last of Grahams special coating, I thought I'd better get a coat of protection on it before the brown stuff started to re-appear. After removing all the flashings with my Dremel and filling a lot of the imperfections with car body filler, I applied a first coat of high build primer, which just showed up even more that need filling!
I have yet to cut the keyway, so some of this coat will inevitably get damaged then, but it will need several more coats anyway once all the filling and rubbing down has been finished.
In case you are thinking that my choice of colour is a bit odd, I studied the tin for ages before I bought it and nowhere did it say what it was, so the cream/pale yellow colour was a complete surprise!

Title: Re: A Robinson from rejects.
Post by: Jasonb on February 25, 2018, 05:42:58 PM
As the Robinson flywheel is quite fat I could not get either the jaws from either the 3 or 4 jaw chucks in between the spokes so used the faceplate. A piece of hardboard between flywheel and faceplate allowed me to run the tool right across the face and also allowed for any slight undulations on the unmachined casting to seat down firmly. The iron was softer at either edge of the rim and decidedly harder towards the middle with a marked increase in noise from the tool as it moved from one to the other. Maybe Graham had been melting down manhole covers and drain gratings of iffy supply to do these castings :LittleDevil: I bored it out to a firm pushfit on the completed crank which will mean no wobble.

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02614_zpshpwbhjo9.jpg)

I knew from the photos that Graham had sent me prior to purchase that there were defects on the other side of the flywheel and suspect I may need more than one coat of High Build filler/primer to deal with these ;) I quite like the cream colour of the UPOL High5 version of this paint and actually use dit as the colour for the small oscillator I built over Christmas, comes up OK with a coat of clear gloss over the top.

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02616_zpswf7q0exn.jpg)

After a good seeing to with a grinding bit in the Dremel it was time to slip all the bits together.

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02621_zps5htzg3jt.jpg)

The exhaust block casting had been consigned to the Rejects pile due to some mold shift so I took the angle grinder to it which got it back into something like the right shape.

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02618_zpsqypk0z6c.jpg)

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02619_zpskeoacrdm.jpg)



While doing this the sparks were coming off quite bright and big not the small fine red ones you should get from a nice graphite rich cast iron so I played safe and gave it a cooking.

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02620_zpsnm0xi1ei.jpg)

Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on February 25, 2018, 07:00:40 PM
It's Robinson mania.

Your engines coming along nicely Jason and looking at the flywheel that Ray has just painted a light colour seems to suit or offset the chunkiness, doesn't it?

Young Alan's been a little busy today!   ;)

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: RayW on March 01, 2018, 07:32:00 PM
Just been thinking about lubrication for the little end. I have drilled a hole in the top of the little end block of the con rod and through the little end bush, but how does any oil get to the con rod in the first  place? Should there not be a hole in the piston to allow oil to reach the inside of the piston from the cylinder wall?
Title: Re: A Robinson from rejects.
Post by: Jasonb on March 01, 2018, 07:41:41 PM
I put a hole in mine
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on March 02, 2018, 11:25:51 AM
Good morning Ray.

Before you go drilling holes ď willy nilly ď just consider the engines arrangement, Mr Robinson was an amazing designer.

Because the piston is facing downhill, so to speak, oil that passes from the sight feed lubricator onto the cylinder wall is scraped back and deposited into the piston. Effectively the gudgeon pin and bush are
ď awash ď with oil. With horizontal and vertical arrangements this situation cannot happen.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: RayW on March 02, 2018, 12:27:40 PM
Good point Graham. That's one less hole to drill. Still waiting to do the flywheel keyway but can't face an icy workshop yet. Must do some drawings for the sight feed lubricator ready for when it warms up a bit.

Regards Ray

P.S.Did you get the car sorted out or are you still stranded?
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on March 02, 2018, 01:28:40 PM
Hi Ray.

No we're still stranded, the electric pump has been playing up for a little while, but now the fuel is a little waxier, nothing. There's a new one on its way.

The Robinson engines were fitted with a " wine glass " lubricator but finding a 1" genuine one these days would be impossible. I had a quick look on eBay it seems the Chinese are still producing 1" by 1/8" BSP lubricators in both Brass and Steel, the Steel ones being ridiculously cheap!

Going back to my rallying days, on our circuit the Holland brothers always seemed to have a few nice examples available at reasonable prices.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Jasonb on March 02, 2018, 02:31:31 PM
The Robinson engines were fitted with a " wine glass " lubricator

No doubt Jo will be needing one of those for her Robinson.

Should not be too hard to turn up the bowl shape from a bit of acrylic rod and polish it up with some Micromesh. rest can just be like a cylindrical one.
Title: Re: A Robinson from rejects.
Post by: RayW on March 02, 2018, 02:36:30 PM
Looks like I will have to make a slightly bigger version of the ones that I made for the Otto then! I  still have the full size one that I scaled them from, so will use that as a pattern again. This time, I might actually do some drawings first.
Jason has kindly offered to email me some oiler plans, so might even be able to adapt those.

Hope the car is fixed soon, not that the roads are in a fit condition to drive on anyway. Just started snowing hard again here, so staying indoors and keeping warm.

Regards

Ray
Title: Re: A Robinson from rejects.
Post by: ettingtonliam on March 02, 2018, 04:05:54 PM
Not strictly a Robinson from rejects, but I understood that Anson Museum were marketing a couple of the Alyn Foundry designs. I've looked on the Anson site, and can't find any mention. Have I got it wrong?

Richard
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on March 02, 2018, 04:16:46 PM
Hi Richard.

Not wrong but things are on hold at the moment.

Sadly with the passing of certain volunteers Geoff has been having to focus on the more pressing museum matters at the moment.

Weíre hoping to move the Gardner patterns to a foundry thatís a little closer and a lot cheaper than present and expand the range to include the R.L.E. and Robinson ď X ď type.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Jasonb on March 03, 2018, 08:15:12 PM
Bit of an exhausting day.

The cooking of the exhaust block did the trick and it machined up nicely though I did have to deviate from the drawings in a few places to make my worst of the rejects casting work. Also made the Exhaust valve, spring collet, tappet, Eccentric rod guide pin and end plug.

One item that did give me problems was the hole for the pin that stops the gearbox rotating, barely managed to drill it and blunted the drill good and proper, took a few more teeth off an old 2BA tap trying to cut a thread and then found the hard spot had made the drill wander so the pin did not line up with the hole. So ended up plunging the hole with a 1/4" carbide slot drill which still struggled and made a pin with a spigot to fit this hole and a small flange to locate it and will JB Wled that in place.

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02630_zpsj7mpcros.jpg)
Title: Re: A Robinson from rejects.
Post by: Jasonb on March 04, 2018, 05:19:07 PM
I decided to do the conrod next. Squared up the ends and ctr drilled both then drilled and tapped for the bolts before sawing off the cap and cleaning up the cuts.

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02631_zpsoulumnec.jpg)

Bored the big end and reamed the little end

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02632_zpsxll1kk92.jpg)

Bit of turning using a round insert in a MGEH holder which gives a nice 1.0mm radius to the internal corners

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02633_zps6mxqssle.jpg)

Job done, big end bronze has just been soldered up so that will be ready to machine next time.

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02634_zpsgco7h8im.jpg)

J
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on March 04, 2018, 05:33:40 PM
Hi Jason.

Getting closer now! That's pretty much the way I used to make them.

I do however see a slight flaw....

The Robinson has a tapered connecting rod.  ;)

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Jasonb on March 04, 2018, 05:57:05 PM
I could not decide what was drawn as the view from above looks parallel, but looking again it does mention a taper but my drawing has a black blob over part of the writing.

All is not lost as I turned it 5/16 parallel so easy enough to taper it down to the 1/4" at the little end :)
Title: Re: A Robinson from rejects.
Post by: Jasonb on March 07, 2018, 08:15:14 PM
Graham will be pleased to know that I now have a tapered conrod and it seems to have also aquired some bearings.

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02636_zpsurda268j.jpg)

With that done I could not resist seeing what the engine turned over like. No rings but it sounds rude promising and sorry that the camera moved so the loctite is more in focus than the inlet valve.

http://www.youtube.com/watch?v=S4Vnfcvv7bU

J
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on March 08, 2018, 11:46:39 AM
Hi Jason.

The ď rude ď noise is just whatís needed, not much more to do now!

Spring 2018 is seeing new life to old castings!   :)

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: RayW on March 08, 2018, 03:13:33 PM
By sheer coincidence, I too was playing with the Robinson yesterday and producing that amusing noise (the engine that is, not me!).
I still have a couple of little jobs left to do - drilling the hole for the gearbox locating pin and drilling out the hot tube to accept the 11mm burner.
Last thing is the flywheel keyway. I have cut it parallel, and now need to file the slight taper in it to match the key. To my annoyance, it looks at the moment as if there is a slight wobble on the flywheel despite me having set everything up on the lathe to run true to within a thou or so before boring the centre.I will check on the lathe that the crank is running true and see if the key pulls the flywheel true once the keyway has been tapered. Failing that, I will have to consider boring out the flywheel and bushing it before re-boring and re-cutting a keyway.
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on March 08, 2018, 06:11:41 PM
Hi Ray.

Before you go a boring, put a piece of 1/2" Silver Steel in the lathe, clock it for truth and slip the flywheel on. It might be that the crankshaft has a slight warp not the flywheel itself.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on March 08, 2018, 07:19:20 PM
Hello All.

I've attached a photograph of the sight feed lubricator that's fitted to my full size Robinson XP.

Note the extra long thread that's used to hold the front of the crank guard down.

Overall length is 6 inches and the glass is approximately 2" diameter at the top and approximately 1" diameter at the bottom. Glass length is 2 1/4 ".

I know Jason is going to make a replica using Acrylic, this is something I've never done and I will be very interested in seeing the final outcome.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Jasonb on March 08, 2018, 07:34:51 PM
Thanks for that Graham

While you are on are the "trumpet" shaped main bearing oil cups you show on teh drawing original? I was thinking of knocking a couple more like these as the shape would complement the wine glass one.

(http://img.photobucket.com/albums/v156/jasonballamy/Engineering/Cameron%20Steam%20Pump/IMAG3522_zps292e61bd.jpg)
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on March 08, 2018, 07:50:18 PM
Hi Jason.

I had to go back to page 13 to look at the original engine!

No, is the best answer. I used a little " license " and came up with those oil cups myself. Looking at the original they seem to be simple " screw cap " greasers.

Feel free to " license " your own version.   ;)

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Jasonb on March 09, 2018, 08:36:22 PM
And for your evening entertainment here is a half finished lubricator

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02646_zpsel7cnxon.jpg)

Started with some 20mm dia acrylic bar, drilled it out and then bored it using a router cutter to get the internal radius

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02640_zpseowpaqbe.jpg)

Quickly ground up a form tool for the external radius

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02641_zpsolcziqsu.jpg)

Then worked my way down through the grits with some Micro-Mesh

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02642_zps7sqcxanz.jpg)

Came out quite nice and clear

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02643_zps7kxwpfht.jpg)

J
Title: Re: A Robinson from rejects.
Post by: Gas_mantle on March 09, 2018, 08:39:59 PM
Wow that turned out nicely, I'm suprised how clear it machined  :)
Title: Re: A Robinson from rejects.
Post by: Ian j on March 09, 2018, 08:44:30 PM
That's superb Jason. Must have another "play" with my engine now the workshop has warmed up a touch!
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on March 09, 2018, 08:50:54 PM
Wow that turned out nicely, I'm suprised how clear it machined  :)

Indeed....

Well done Jason.
Title: Re: A Robinson from rejects.
Post by: ettingtonliam on March 09, 2018, 09:16:15 PM
Speaking of oiling, what if any were the arrangements for the hot air engine? Did it have a cylinder oiler and a lubricator on the crankshaft bearing? Oil holes in the various links and rods?

Richard
Title: Re: A Robinson from rejects.
Post by: Steamer5 on March 10, 2018, 08:40:47 AM
Hi Jason,
 Just caught up. The taper on the conrod makes a big difference! A small change just seems to make things look so much more eye appealing!

The sight glass is pretty nice too!

Cheers Kerrin
Title: Re: A Robinson from rejects.
Post by: Ian S C on March 10, 2018, 01:37:56 PM
A full size motor And it's piston showing the oiler.
Ian S C
         
Title: Re: A Robinson from rejects.
Post by: Jasonb on March 10, 2018, 04:29:24 PM
Drip oiler finished

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02648_zpsi7syjrc1.jpg)

And a couple of cups for teh main bearings, not sure about the size of the hex, may mill it down by 1/16"

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02651_zps4bfym6ys.jpg)
Title: Re: A Robinson from rejects.
Post by: Craig DeShong on March 11, 2018, 09:44:25 PM
Very Nice  :ThumbsUp:
Title: Re: A Robinson from rejects.
Post by: Ian j on March 13, 2018, 04:58:47 PM
Latest progress!
Made a couple of changes:
replaced the Chinese Honda CI piston rings with 2.5mm C/S Viton O rings.
made a better  seal of the ignition tube into the cylinder using a copper washer.
I don't mind admitting to my C*** ups, I had  forgotten  to cut the exhaust port opening in the exhaust gasket ! No wonder I had such good compression :)
Another problem is the gas burner getting blocked ( I remember you mentioning this Graham when we met up at the Anson Museum)
Now using a small pinpoint gas torch to heat the ignition tube I can get it to fire a couple of times in succession ( that's 200 percent better than before)
Just to confirm that the direction of rotation is anticlockwise as you look at the fly wheel side? The reason I ask is some times after firing it try's to go clockwise.
Any way that's it for now.
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on March 13, 2018, 05:59:14 PM
Hi Ian.

Great news indeed, and yes anti-clockwise it is.

With the engine trying to go backwards it is suggesting early ignition ( advanced ) try holding the flame a little higher up the tube. This should retard things a little. If you're finding your having to place the heat too far up you might need to make another tube with a fractionally smaller internal diameter. This effectively alters the parameters. In imperial measurements we used to try 1/64" either side of 1/8"

Oh, before I forget, the jets in those burners can usually be unblocked by putting a reverse pressure from the likes of an unregulated CO2/Nitrogen gas bottle or possibly the max pressure from an air line.

Cheers Graham
Title: Re: A Robinson from rejects.
Post by: Ian j on March 13, 2018, 06:09:07 PM
Thanks for that Graham I will refit the original ignition tube made as the drawings.
Will give the compressed air method to unblock the burner a try.
Title: Re: A Robinson from rejects.
Post by: RayW on March 15, 2018, 05:49:10 PM
Finished the oiler today and quite pleased with the result. The attached photo shows the original full size one together with the Robinson one in the centre and the Otto one on the right.

Ray
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on March 15, 2018, 05:55:47 PM
Very nice Ray, well done!

How's the " plumbing " coming along?    ;)

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Jasonb on March 15, 2018, 06:01:17 PM
They look good Ray

talking of plumbing what are people doing, will you make an adapter to fit the burners M8x0.75 thread with a more common 1/8" BSP on hte end so it can all be plumbed in with BSP or are you going to do it all in metric or a bit he ME thrown in? Or bodge it and stuff a 5/16x 32ME into the burner ;)

I got the gib key for the flywheel made and fitted last night and no sign of a wobble, also made a greaser for the crank as well as bit for the R&V engine so that can bet test run at the weekend.
Title: Re: A Robinson from rejects.
Post by: Ian j on March 15, 2018, 06:32:19 PM
My "plumbing"
I made an adapter threaded M8 x .75 to screw into the burner with 1/4" copper tube silver soldered coming out at the bottom, the other end has 1/4" pipe nipple and 1/43/8" x32 ME pipe nut to screw onto the gas valve via another adapter which were 1/4 1/8" BSP. In hind site this gives no vertical positioning adjustment of the burner to advance/retard the ignition.But hay ho I can change it ;D
The inlet to the low pressure valve is via a No.60 drill diam hole.



Title: Re: A Robinson from rejects.
Post by: RayW on March 15, 2018, 06:58:59 PM
Hi all.
I have not got as far as the plumbing yet, but will probably opt for an M8 to BSP adaptor. I like Ian's neat setup, but would need to adapt it to allow vertical adjustment of the burner, possibly by incorporating a flexible section of hose into the feed line to the burner.
I have decided to live with the slight flywheel wobble for now, and sort it out once the engine is running, at which point I will strip it down for painting.

Ray
Title: Re: A Robinson from rejects.
Post by: Ian j on March 20, 2018, 01:05:02 PM
IT LIVES !!
I made a couple of important discoveries this week end.
I had taken the 2 3/16" dimension on the eccentric strap from the outside circumference rather than the inside so I was nether going to get the exhaust valve timing correct. Also I found out after all these years my gas bottle was fitted with a low pressure regulator, once changed the burner now roars and the ignition tube glows bright red. Also changed the burner feed tube to allow vertical adjustment ( same as on Grahams)
 It appears to be quite tolerant of the exhaust timing but less so on the ignition tube and volume of low pressure gas , in fact I was surprised how little gas is required for ignition.Attached is a link to video (poor quality) The fly wheel doesn't wobble as much as it looks it's more camera shake!

PS. The piece of plastic on the end of the crank shaft is to stop me slashing my thumb again :'(

http://www.youtube.com/watch?v=Csxf9inFBAE
Title: Re: A Robinson from rejects.
Post by: Jasonb on March 20, 2018, 01:15:34 PM
looks and sounds good, your soldering torch should also work a lot better with the HP regulator :)

I did not do much to mine at the weekend, just made the M8 x 0.75 to ME adapter, cut the keyways and made the key.
Title: Re: A Robinson from rejects.
Post by: Chipmaster on March 20, 2018, 02:38:29 PM
Sounds great Ian, congratulations. Can we have a longer video of the engine please.

Andy
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on March 20, 2018, 03:33:55 PM
Well done Ian.

So now, with a few lessons learned, will April see number 198 running?   ;) :)

I also concur with Andy, more footage!   :ThumbsUp:

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Ian j on March 20, 2018, 03:43:21 PM
What makes you think it runs for more than 50 secs ?  :)

It does but for some reason my camera stopped recording/saving . Will make a longer video after a few finishing touches, studs for the bearing caps etc.

As for No. 198 which April ? ;)
Title: Re: A Robinson from rejects.
Post by: RayW on March 20, 2018, 05:18:44 PM
Brilliant Ian. Runs really well. Must get my plumbing sorted out so that number 197 can join the ranks of running Robinsons.
Look forward to more video soon.

Ray
Title: Re: A Robinson from rejects.
Post by: Jasonb on March 24, 2018, 10:57:17 AM
A needle valve dropped onto the doormat yesterday so last night I played with the plumbing.

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02678_zpsltbbhzyr.jpg)

Though it is an 1/8" BSP valve it comes up a bit larger than I would really have likes and the plastic knob will more than likely get changed but it will do for now. I have opted for a single valve the same as Grahams setup, any adjustment to the burner can be done on the cylinder regulator and the engine will still get more than enough gas.

I did think about going for the solder plug and pricking a pin hole in it and could still revert to that but for now have drilled a 0.3mm ( 0.012") hole into the union from tee to valve.

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02675_zpsw1r1e0og.jpg)

I use one of the sliding chuck holders from ARC which gives more feel than using the tailstock handwheel even then I had to take it easy to prevent the drill from bowing.

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02676_zpsuzq66w9d.jpg)

Just need to solder it up now.
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on March 24, 2018, 11:50:01 AM
Good morning Jason.

So close, I can almost feel the excitement building!

On a precautionary note, before trying a run, remove the gas burner and " purge " the pipe work using the gas from the bottle. This, hopefully will remove any tiny particles from the lines that could potentially block the gas jet.

I agree the control knob leaves a lot to be desired but I'm pretty sure you will make something more in keeping once the engine has been run.

We discovered way back that the best way to control these " small power " gas engines was with a valve as close to the engine as possible. This ensures the changes that are made happen almost immediately rather than a line full of gas which could take several seconds to alter and by that time stop the engine. Yes, yet another " Teeshirt " !!

Good luck Jason, looking forward to the video.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Ian j on March 24, 2018, 02:10:53 PM
Very neat set up Jason. What size copper pipe have you used for the coil? I used 1/4" but I think smaller would be more flexible.
Graham I note what you say about the valve been close  to the inlet port makes the gas adjustment more sensitive.I can feel some rework happening on mine.
Title: Re: A Robinson from rejects.
Post by: Jasonb on March 24, 2018, 07:51:59 PM
I went for 5/32" pipe. Annealed it and it would round a bit of 1" bar very easily.

Am I right in thinking that the easily blocked jet in the burner is so small you can't easily see it by eye as I can't get gas out of mine. :'(
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on March 24, 2018, 08:11:31 PM
Hi Jason.

Yes, it's really tiny.... don't try to " prick " it.

I've unblocked a few successfully by using a high reverse pressure applied to what would be the exit. If you've got CO2 welding kit the direct bottle pressure is more than powerful enough to blow any debris back the way it came.

A little known fact about Propane bottles is that over time and refilling a powder called " heavy ends " builds up inside. This whitish dust can easily block small gas burners, we killed several burners by moving the bottles around while the engines were running.

Keep us posted....

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Jasonb on March 24, 2018, 08:21:24 PM
Well it was a bit more than a spec of white powder. I put a 00000 size artists paintbrush in the end very lightly and just gave it a twist and look what came out on the end. Must have got in there in the last week or two as I blue the gas out of the line and my plumbing before connecting to the burner. have a feeling I did put it in my back pocket one time so I did not drop it while carrying the engine down to the workshop, so now we know what Bum Fluff looks like and what it can do to your burners.

Hopefully have another go tomorrow.

Hole shows up better in the photo than it does under a magnifying glass, for those that don't have one of these burners the flat end of the male thread is about 7mm across.

Also shows that you don't need very large pipe going to the burner as gas only has to fit through this hole
Title: Re: A Robinson from rejects.
Post by: Ian j on March 24, 2018, 08:24:21 PM
I unblocked mine by unscrewing the jet from the  burner tube and screwing it onto an adapter  (M8 x .75) and connecting it to my compressor at max, worked for me, might have been  just lucky.
Title: Re: A Robinson from rejects.
Post by: Jasonb on March 24, 2018, 08:26:10 PM
I was going to try the airline in the morning if that had not worked, was hoping the tire inflator might have fitted straight onto the thread.
Title: Re: A Robinson from rejects.
Post by: RayW on March 25, 2018, 07:52:18 AM
Are you sure that's not my needle valve Jason? I ordered one that was supposed to arrive either Friday or Saturday  but hasn't arrived yet!

Ray

Title: Re: A Robinson from rejects.
Post by: RayW on March 27, 2018, 01:22:15 PM
Looks like Jason and I shop at the same place as my needle valve looks identical to his apart from the fact that mine has male BSP connections, not female.
I have got rid of the black plastic handwheel and made a brass one which, I think, looks much better. Just waiting for an M8 x 0.75 die now to make a connector for the burner, the I should be able to get the pipework finished.

Ray
Title: Re: A Robinson from rejects.
Post by: Ian j on March 27, 2018, 01:43:24 PM
Ray.That looks a nice size valve, where have you and Jason found those? Think I need to change mine.
Title: Re: A Robinson from rejects.
Post by: Jasonb on March 27, 2018, 01:54:15 PM
I'm not totally happy with mine as it only needs the wheel turning about 2 degrees to go from no gas flow to a flame thrower when I try it without the valve in place so getting that 1" flame that Graham says we need is not easy. This was the one I got.

https://www.ebay.com/itm/EV-18-1-8-BSP-FEM-BRASS-NEEDLE-VALVE-Airpro-Aignep-Valves/222147351429?ssPageName=STRK%3AMEBIDX%3AIT&_trksid=p2057872.m2749.l2649

I did not get much time in the workshop at the weekend so only managed to get a few pops out of it.

Out of interest graham and Ian how hot does your hot-tube get? should it be red hot as mine is not getting that hot and the pops were with an additional small blow torch.
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on March 27, 2018, 01:56:11 PM
Hello All.

I used to use Wade 3/16" needle valves, the 3/16" designated the pipe diameter, they had 1/8" BSP Male threads.

I've just looked on eBay, my goodness how prices have risen over the years! I can see the valves that both Jason and Ray have found were a lot cheaper.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on March 27, 2018, 02:04:34 PM
Hi Jason.

I see our posts crossed.

What you're looking for is an Orange spot on the tube where the hottest part of the pencil point burner wraps its flame around.

I does read like the needle valve isn't very finely adjustable, you might need to further restrict that neatly made restrictor ?

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Ian j on March 27, 2018, 02:28:35 PM
"Out of interest graham and Ian how hot does your hot-tube get? should it be red hot as mine is not getting that hot and the pops were with an additional small blow torch."

This was the problem I had until I discovered my gas bottle was fitted with a low pressure regulator. Once a HP regulator was fitted the burner is a lot louder , similar to the sound in Graham's video .

I've spent hours on the internet looking for suitable valves. I found "Wade Comp. Mini Needle Valves - 3/16" Stainless Steel Spindle (Part No. WVA1/SS/12)" for £16 which seemed ok until you have to have £12 next day delivery + VAT=£34.38. What I need is a local plumbers merchant selling them at £16.Will carry on searching and let you know.
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on March 27, 2018, 03:13:54 PM
Hello All.

Maybe this will help?

q9-Z0ITmzZ0
Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Jasonb on March 27, 2018, 03:44:22 PM
Thanks for that Graham way hotter than I am getting as I don't even get an oragge glow let alone the hot spot. The Regulator is a 0-2 bar one turned right up though it was on my old bullfinch torch which seemed to have lost power over the years so maybe it is not letting through as much gas as it should.

I did find the wade valves but as they were about double I went with the cheaper option. This is the "needle" which looks to be more suited to knitting baggy jumpers than what I would have expected for fine adjustment :headscratch:.
Title: Re: A Robinson from rejects.
Post by: RayW on March 27, 2018, 03:58:28 PM
Ian,

If you search for item number 262483692006 on ebay, you will find my valve. I haven't taken mine apart yet so don't know if the needle is the same as Jasons.

Ray
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on March 27, 2018, 04:16:03 PM
Hi Jason.

Yes indeed, more like a " Bodkin " than a sewing needle!!

If memory serves the burners we're using were known as the Primus 2000 range. Designed to run via a valve and stem directly off the bottle. They were favoured by Plumbers as the bottle was very easy to handle and use.

Your 2 Bar equates to approximately to 30 PSI  way short of the near 100 PSI that can be got from an unregulated bottle. I've never actually measured the pressure I'm using but I'm probably up at 50 PSI.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Jasonb on March 27, 2018, 04:28:19 PM
With a different neck tube that burner will run of my Sievert torch. I have that torch on a 4 bar regulator so may try that but will need to make an adapter.

The can regulator that I used for the Chuky burner gave a very fine adjustment so might try that to feed the engine and the 4 bar reg on the hot tube.

I've also got some nice fine regulators that I have on a manifold to run the steam engines on air which would be another option.

Just looked at the Sievert catalogue on line, on page 16 they show the burner and the central blue cone is about twice the length I was getting so definately something not right.

http://www.sievert.se/wp-content/uploads/2016/11/Sievert-Catalogue-UK-2016_web.pdf
Title: Re: A Robinson from rejects.
Post by: Ian j on March 27, 2018, 04:59:56 PM
My newly fitted HP regulator is 0-4 Bar turned right up .
Title: Re: A Robinson from rejects.
Post by: RayW on March 29, 2018, 08:24:06 PM
Something really odd is going on with these burners. I had a look at mine today and lo and behold, the back end contained this plug of cotton wool type material exactly the same as Jasons. I am wondering now whether this is there deliberately as a sort of filter to stop any small particles from blocking the jet?
I will e-mail Sievert to see what they say.

Ray
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on March 29, 2018, 08:36:41 PM
Hi Ray.

Very odd indeed!

Perhaps Sievert have actually done something to try and prevent those " heavy ends " from blocking the very tiny orifice.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Ian j on March 29, 2018, 08:45:02 PM
Will be interesting to see what Sievert say.
Title: Re: A Robinson from rejects.
Post by: RayW on March 29, 2018, 08:46:30 PM
I have e-mailed them but they are closed until after Easter now. Will report back on their response.

Ray
Title: Re: A Robinson from rejects.
Post by: Chipmaster on March 30, 2018, 10:01:27 PM
Over the last 20 years I have also been using those Sievert 8852 burners in my Alyn Foundry Gardner 0 Type and have always taken spare burners to rallies in case the jets become blocked. I have a stock of five burners and each of them had the little felt pellet which I also presumed was a filter. I have always been able to clear them with a reverse blast of compressed air. However, I leave the filters out to ensure whatever caused the blockage has gone.

Here's a YouTube video of my hot tube  :o it shows two burners, one working at high pressure and the other at 2psi.
8Ld5cWtwtf0
Andy
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on March 31, 2018, 11:08:12 AM
Hi Andy.

Oh my, what a magnificent " hot tube " !!     ;D

Lovely to see the Gardner running so well, I presume the last bit of the video was using the LP burner into the " proper " gas ring ?

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Chipmaster on March 31, 2018, 03:39:05 PM
Hi Graham, pleased you were impressed by my hot tube.
You're right the last bit was indeed a proper gas ring using a 'low pressure' 8852 burner bored out to six thou.
To bore out the Sievert burner I bought a couple of packets of cheap  0.006" / 0.15mm drills from China and also made burners with 0.006" jets from scratch. However, at 2psi my low pressure burners only work with the gas ring, they don't produce a fierce needle sharp flame capable of heating a hot tube.

Andy
Title: Re: A Robinson from rejects.
Post by: Ian j on April 02, 2018, 08:50:50 PM
Re plumbed the low pressure gas  (again) to move the adjustable valve closer to the inlet valve chest using 5/32" tube, re drilled the  adapter to the inlet of the adjustable valve .3mm diam. ( smallest drill I have and see) Fitted studs for the crankshaft bearing caps. Made a new drip oilier ( similar to Jason's and Ray's)
 The engine now starts a lot easier. I experimented with different settings of the gas bottle regulator and found any thing under it's max (4 bar) the ignition tube did not get hot enough. Think I still need to restrict the low pressure gas as you will see in the video how sensitive it is.

http://www.youtube.com/watch?v=LM7m0ZHts5M

OOPs. should be ok now?
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on April 02, 2018, 09:15:32 PM
Hi Ian.

Your video link appears to be missing.

Hello All.

Yesterday was spent at the Anson engine museum for the Spring opening event. In the attached video I'm in charge of the starting and running lamp.

This engine ( at present ) is a sole survivor of its type.... A Robinson type HA.

The governor is particularly interesting, a " Pendulum governor " rarely seen, and working beautifully.

 nlpRdfHx1Vk
Some members may recall my mention of this type of unusual governor some time ago.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: RayW on April 02, 2018, 09:34:50 PM
Well done Ian. Looks like it is running really nicely.Now it's going you can play around with the settings. I am just waiting for a couple of pipe fittings to finish my plumbing, then I have to make up the restrictor to the inlet valve. After that I should be ready to give it a try.

Ray

Graham, that's a really nice engine at the Anson. No doubt the excellent running was due in no small part to the skill of the blowlamp operator!
Title: Re: A Robinson from rejects.
Post by: scalemodel on April 02, 2018, 10:13:04 PM
Ian,
That is a nice model and running wel the more you play around with the gas the better it will get.

Graham
That robinson would make a lovely model

Jonathan
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on April 03, 2018, 11:13:14 AM
Yes, well done Ian.

You can now understand, first hand how delicate the fuel control is!

Because of the truly heavy flywheel the Robinson seems to fire every other stroke once all is set nicely, I noticed that in your video, with a nod of approval.

The HA above was Robinson's ( tank cooled ) horizontal range that were built along side the " oblique " range that you're all building. The " pendulum " governor was also fitted to these on occasions. I'm not actually suggesting someone should try this, but....  As a cautionary note, for this form of governor to work properly the engine itself needs to be firmly anchored to a substantial base to prevent it rocking and ensure the pendulum swings.

Jonathan....

                     ;)

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: RayW on April 03, 2018, 04:32:57 PM
Hi all,

Got a reply from the Sievert man today regarding the "cotton wool" plug in the back of the burner:

"That is a filter. As the orifice is 0.07mm in diameter it will block quite easily particularly if liquid propane tries to go through it so the filter helps most of the time".

That confirms what we suspected.

Ray

Title: Re: A Robinson from rejects.
Post by: Jasonb on April 03, 2018, 05:21:25 PM
Bu**er, now I need to find where that bit of fluff went ;)

Did not do anything on this one over the Easter but got another engine almost complete and played about trying to get the R&V vertical running - previous owner had made the needle valve hole too big so the needle just poked right through  :facepalm: Got a few more pops out of it with a new oversize needle but needs some more time spent fine tuning the ignitor.
Title: Re: A Robinson from rejects.
Post by: Ian j on April 03, 2018, 05:27:50 PM
Double bu**er. I never noticed if mine had any in,if it did it hasn't now. Is it just cotton wool?
Title: Re: A Robinson from rejects.
Post by: Ian j on April 05, 2018, 01:29:31 PM
A bit of tinkering this morning. Fitted a No.3 (.15mm) burner jet between the outlet of the needle valve and the inlet valve chest, this has improved the gas adjustment.
 Remade the key for the fly wheel which has got rid of some of the wobble ! and the clonking sound ( fly wheel was loose.)
Title: Re: A Robinson from rejects.
Post by: zeeprogrammer on April 05, 2018, 06:36:27 PM
Just ran through this thread. It's certainly full of fun and interest.
But I'm confused. How many engines are there and who all is building? :thinking:
Title: Re: A Robinson from rejects.
Post by: RayW on April 05, 2018, 07:45:54 PM
There are three current Robinson X type builds covered in this thread, by Jasonb, Ian j and myself.

RayW
Title: Re: A Robinson from rejects.
Post by: crueby on April 05, 2018, 07:52:10 PM
There are three current Robinson X type builds covered in this thread, by Jasonb, Ian j and myself.

RayW
Ah - okay, I was confused too!
Title: Re: A Robinson from rejects.
Post by: Jasonb on April 05, 2018, 07:54:13 PM
I thought the thread started with the one Graham is building so that makes 4 though he is a bit slow ;)

Jo has also got a set or two of X-type castings
Title: Re: A Robinson from rejects.
Post by: RayW on April 05, 2018, 07:58:44 PM
I stand corrected Jason. How could I possibly have forgotten Graham's own engine! My apologies to him for the oversight. I didn't mention Jo as I didn't think she was actually building a Robinson at the moment, even though she has castings

Ray
Title: Re: A Robinson from rejects.
Post by: RayW on April 18, 2018, 07:38:42 PM
I seem to have got sidetracked lately with other things and have not done much on the Robinson, but finally got the pipework finished and fired up the burner for the first time today. Initially only got a rather small weak flame, then realised that the gas bottle was probably getting low! With a new bottle, there was a really good fierce flame, which brought the tube up to red heat pretty rapidly, so I should be attempting a first start-up any day now. Watch this space!!

P.S. If you are reading this Graham, I hope that you are feeling better now.

Ray
Title: Re: A Robinson from rejects.
Post by: zeeprogrammer on April 18, 2018, 07:39:57 PM
Watch this space!!

 :ThumbsUp:
Title: Re: A Robinson from rejects.
Post by: Ian j on April 18, 2018, 07:47:57 PM
Neat gas arrangement Ray. Looking forward to seeing it running.
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on April 19, 2018, 12:57:52 PM
Hi Ray.

Looking good!!  :ThumbsUp:

I'm still under the weather, thanks for asking, your first run will definitely cheer me up.

Cheers Graham.



Title: Re: A Robinson from rejects.
Post by: RayW on April 19, 2018, 03:52:21 PM
Hi Graham,

Things did not exactly go according to plan today. First attempt to start once the hot tube was nice and red resulted in the engine erupting in flames as soon as the gas inlet valve was opened! Big panic as it was on the rubber covered floor of the workshop but luckily the wooden base that the engine is mounted on prevented flames reaching the floor.
Quickly turned off gas and allowed flames to go out. It became obvious that there were some leaks in my pipework, so dismantled every joint and re-sealed them all.
Took engine outside to try again and got a couple of chuffs, but still repeatedly burst into flame almost every time that I opened the gas inlet valve.The fire happens so fast that it is impossible to see where it originates. I re-tightened the nuts holding the inlet and exhaust valve blocks in case there was a leak there.
Final attempt resulted in no more flames, but no sign of any attempt to run.
I am wondering if a lot of oil has drained down into the cylinder head and is igniting when gas is admitted to the cylinder and is ignited by the hot tube. On the first occasion that it caught fire, flames were actually coming up past the piston at one point.
Any suggestions please?

Regards and get well soon,

Ray


Title: Re: A Robinson from rejects.
Post by: Ian j on April 19, 2018, 05:24:09 PM
I think Jason mentioned that that type of needle valve wasn't very sensitive ie from no gas to load of gas.
My needle valve only requires approx 1/12 of a turn to deliver sufficient gas and that is with a number 3 burner jet (.15mm) between the outlet of the needle valve and the inlet valve chest.
Title: Re: A Robinson from rejects.
Post by: Jasonb on April 19, 2018, 06:39:10 PM
Yes mine was giving too much gas and would flare up from the exhaust which makes things exciting :o
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on April 19, 2018, 07:51:51 PM
Hi Ray and All.

The gas control on your needle valve does seem rather ineffective but as I mentioned many pages back the inlet valve always leaks a little.

What is actually happening is the leaking gas is being ignited by the flame from the hot tube burner.

My only suggestion is to perhaps make a better needle that actually plugs up the hole more effectively and try to reduce further the gas input before the needle valve proper.

I will confess that my engine has flared up many times over the years too.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Ian j on April 19, 2018, 08:43:21 PM
Before I connected the gas to mine I tested the pipe connections with compressed air connected and a brush with soapy water.
Title: Re: A Robinson from rejects.
Post by: RayW on April 20, 2018, 04:39:36 PM
Thanks all for the feedback. It is reassuring to hear that the experts (Graham) engine also spontaneously combusts occasionally!
I did put a restrictor in the inlet pipe to the needle valve, but re-reading all your previous postings, I clearly made the hole much too big as I used a Number 60 drill bit, which is about 40 thou. Fortunately, I deliberately made this a removable screw-in restrictor, so no problem to replace it with another with a much smaller hole.
I have also had another look at the "needle" valve internals, and I think it would be quite easy to modify it if necessary. I will try the smaller restrictor first and see if that helps.
When I first assembled the pipework, I sealed every threaded joint with special Calor Gas sealant, so I had no reason at that stage to suspect any leaks, but when some became evident, I did use soapy water to find them Ian. Unfortunately, I do not have a source of compressed air so had to resort to blowing through the pipework by mouth while immersing it in water.
Title: Re: A Robinson from rejects.
Post by: RayW on May 07, 2018, 02:40:45 PM
Tried the engine today with a modified restrictor before the needle valve. Reduced the bore from 40 thou to about 13 thou. Still tending to erupt in flames and no sign of any attempt to fire at the minute. Noticed slight bubbling from the inlet valve gasket so that is probably where the gas was leaking and igniting. Have resealed with silicone gasket sealant and will allow to cure overnight before trying again.
I will also try capping off the supply to the burner so that I can check exactly how much gas is getting to the cylinder and how well the needle valve is regulating the flow.

Ray
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on May 07, 2018, 04:04:04 PM
Hi Ray.

Still reads like too much gas....

Try this, extend the exhaust a little from the valve chest using some metal pipe. Anchor the engine and with a candle flame burning under the exhaust outlet start trying to turn the engine through its cycles.

If too much gas is present the exhaust will ignite with a very Yellow flame, what you're looking for is a Blue flame. Blue indicates a near perfect mix of fuel to air. It's a simple and effective way of fine tuning the mixture of a gas engine.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Jasonb on May 07, 2018, 04:09:31 PM
I have also had a little try with mine, now got a No3 jet (0.015mm) infront of the valve and using the 4 bar regulator. still don't seem to be getting a very hot tube and no signs of life. Gave up then as it was too hot in the shed to be turning over engines so decided to have a magnum.

13PxqCo1QtM
Title: Re: A Robinson from rejects.
Post by: RayW on May 07, 2018, 05:28:22 PM
Thanks for the suggestion Graham. Sorry to sound stupid, but do you mean to blank off the burner or to do what you suggested with the burner burning?

Jason, the Magnum sounds like a much more sensible suggestion than playing with engines in this heat!

Ray
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on May 07, 2018, 06:37:38 PM
Thanks for the suggestion Graham. Sorry to sound stupid, but do you mean to blank off the burner or to do what you suggested with the burner burning?

Jason, the Magnum sounds like a much more sensible suggestion than playing with engines in this heat!

Ray

Hi Ray.

No, not stupid, I should've mentioned to blank off the burner.

You might find that there's less gas entering than you thought, I'm suggesting a starting from the off position and waiting to see the Blue flame appear. If it's Yellow from the start then there's way too much, ideally what you're looking for is nothing then a small Blue flame then moving to Yellow.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: RayW on May 12, 2018, 12:43:27 PM
Thought I would check how well the inlet valve is sealing before trying Graham's suggestion. Removed the whole inlet valve block and connected to the gas supply, having first blanked off the burner connection. As I suspected, even with the valve appearing to be seated flat against the inlet block, gas is escaping from under the valve head, meaning that gas would be flowing continuously into the cylinder all the time that the needle valve was open.
Tried re-facing the valve and lapping it against the valve block, but even holding the valve down by hand as hard as I can, I cannot get it to seal completely.
I have been thinking about the design of the inlet valve itself and am toying with the idea of trying a modified design to see if that cures the problem. My thought is that part of the problem with the current valve is that it is trying to seal over a fairly large flat area which contains numerous holes including the gas jet. If I made a slightly larger valve and recessed most of the face by a very small amount leaving a narrow raised rim, would that be easier to lap in and achieve a seal? Admittedly, this would allow a very small amount of gas to be held under the valve head until it opened but would that be a problem?
I would be interested what others think of my idea.
Title: Re: A Robinson from rejects.
Post by: Jasonb on May 12, 2018, 01:29:21 PM
You may get gas leaking out through the inlet holes as there will be nothing between them and the gas hole, watch your eyebrows.

May work if you milled a "C" shape to recess all the surface around the air holes but left the area around the gas hole flush with your sealing surface
Title: Re: A Robinson from rejects.
Post by: ettingtonliam on May 12, 2018, 01:36:53 PM
With an inlet valve that seats perfectly, the force trying to lift it off its seat is the combined area of the holes times the gas pressure. If you made a  wider valve and recessed the area containing the holes, the force trying to lift it off its seat is the area of the recess times the gas pressure, which will be much larger.
On the other hand I could be talking rubbish.

When I built my Stuart 600 gas engine, getting the valves to seat properly was one of the most difficult jobs
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on May 12, 2018, 02:42:36 PM
Well....

Even the originals leak!!

I wouldn't be too concerned at this point Ray. Once you've tamed the beast and found its " spot " that weepage won't be a problem.

A question..

Do you have good compression? ie, does the flywheel bounce back against compression? Ideally the flywheel will oscillate back and forth at least twice.

If yes then I'd try the " burning candle " test to see if there's too much gas entering.

Now there's some metals that won't work as an ignition tube, Cuprous being one of them. Iron was extensively used along with ceramic. These days we've got Stainless Steel, the best. Did you follow the dimensions from the drawing? One eighth of an inch internal diameter. This might need either opening or closing depending on your developed compression pressure.

I'd be inclined to blank off the supply to your burner and with the engine firmly anchored try using your favourite gas torch on the tube, get it good and hot then try starting it. You can then see where the
" sweet spot " is. If it's low down, open the diameter by 1/64" if it's high up reduce the diameter by 1/64".

Good luck Ray, we're all agog, cheers Graham.
Title: Re: A Robinson from rejects.
Post by: RayW on May 13, 2018, 05:29:09 PM
Thanks all for your responses. As Jason pointed out, my idea of a recessed valve face would not work as it would not seal off either the gas jet or air inlet holes. Think I must have been having a senior moment when I came up with that idea!

Tried the candle test today, Graham, with interesting results. As Jason mentioned in a previous post, the big blunt "needle" in the valve provides very little control over the gas flow, being more or less on or off. As you will see from the video below, I did eventually manage to achieve a good fierce blue flame with the valve just about cracked open, but turning the handle even a fraction of a degree one way or the other resulted in either no flame or a flame thrower!

KHnzh7-W_aAt=9s
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on May 13, 2018, 06:00:00 PM
Hi Ray.

Yes, there were at least 3 places in your video where the mixture seemed to be just right. Near the end it became consistent.

The only suggestion I have is to perhaps make a replacement needle to try and get a better control over the supply.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: ettingtonliam on May 13, 2018, 07:49:04 PM
Sounds like you were working hard there, lots of heavy breathing!. When I was trying to get the Stuart to run, I rigged up a 1/4hp electric motor on a hinged plate, with a small rubber covered flat pulley on the motor shaft I arranged this at the flywheel end of the engine, with the weight of the motor pressing the pulley against the flywheel. This rotated the engine at about 200 rpm, so I could concentrate on getting the gas and ignition timing adjustments right. When it seemed to be running on its own, I swung the motor away.

Richard
Title: Re: A Robinson from rejects.
Post by: RayW on May 13, 2018, 07:57:05 PM
Hi Graham,
Once I found the right setting the flame remained very consistent. The variations you see on the video were the result of me playing with the setting to optimise the flame. When I try to start the engine I will start with zero gas then open the valve by tiny amounts until it fires (hopefully). I will also look at the possibility of modifying the needle or, if not, finding an alternative valve.

Ray
Title: Re: A Robinson from rejects.
Post by: RayW on May 13, 2018, 08:00:53 PM
Hi Richard,

I meant to apologise in my previous posting about the heavy breathing! It really wasn't that hard turning the flywheel.

Ray
Title: Re: A Robinson from rejects.
Post by: Ian j on May 13, 2018, 08:58:28 PM
Ray.
I feel your frustration with the gas supply problems.
I'm reluctant to make a suggestion on a suitable needle valve but my engine now reliably starts and the speed varied with the set up I have. The needle valve I use is this item on ebay{-

"eBay item number:
253612197055"

Ian

PS. Making good progress with building the second engine from castings.(No.198)
Title: Re: A Robinson from rejects.
Post by: RayW on May 15, 2018, 10:16:10 AM
The beast awakes!
Had another try this morning and, with the tube glowing nicely and the needle valve barely cracked open, it fired and ran on about the second or third spin of the flywheel. The attached video is actually the second run, as I had not even got the camera set up the first time as it caught me completely by surprise when it started!
As was evident when I carried out the candle test, the tiniest change to the needle valve setting stopped it running, so I would still like to get a different valve to give me finer control over the gas supply. For now though, I am a happy chappy.
The run today was, of necessity, only short as the cooling system is not yet operational, the cylinder needing to be sealed to the base, which will be done when I strip the engine down for painting.
Thanks to you all, and in particular Graham, for your continuing support and encouragement along the way.

Ray

x-0odv8w_a4
Title: Re: A Robinson from rejects.
Post by: Jo on May 15, 2018, 10:22:53 AM
 :whoohoo: :whoohoo: Well done Ray

I will have to go and see what Surus  has done with my X Type castings  :noidea:

Jo
Title: Re: A Robinson from rejects.
Post by: Roger B on May 15, 2018, 10:32:51 AM
Splendid  :praise2:  :praise2: Your persistance paid off  :ThumbsUp: Than needle valve is incredibly sensitive  ::)
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on May 15, 2018, 11:18:17 AM
Well done Ray.

Old " H R " would be proud!!

They are a feisty engine, a substantial base is important to stop them leaping about everywhere.

I'm looking forward to seeing it when all painted and its makers plate fitted.

In watching your video I'm beginning to wonder how much the " HA " will leap with another 1/4" of cylinder diameter added?

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: RayW on May 15, 2018, 11:49:38 AM
Thanks Graham, Jo and Roger.
The engine was actually running pretty smoothly, but the Workmate bench it was on was not standing very steadily, hence the jumping about.
I definitely need to make a more substantial base, but need to watch the weight otherwise it will be too heavy for me to lift and carry. Have already had two major back surgeries and don't want any more thank you!
Next job is to make a silencer, then a full strip down and paint. I have seen engines with the circular "flying saucer" type silencer, but does anyone know if that is the correct type?

Ray
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on May 15, 2018, 12:16:44 PM
Hi Ray.

I'm totally with you on the " back " issue!

Regarding the/a silencer, simple fact they never had one! Most of the full size engines I've seen over the years had a short bent piece of Iron pipe with the open end having a Brass ferrule attached. A Rubber hose was pushed over the ferrule and the other end stuck out of the window.

I remember one of my visiting customers telling me of how his father had two Robinson's running equipment in the basement. He, as a child was quite scared because the " gas bags " that were just simply two ended White Rubber bladders looked like they where breathing. It was this " breathing " aspect that frightened him. He bought a kit to remember his childhood.

A nice touch would be an exhaust " bottle " like those fitted to industrial engines, Jason will smile as one of my favourite " tins " was the little Goblin Steak pudding tin, used, turned upside down and made into a silencer. Sadly they no longer come in metal cans.

Sorry, yet another trip down memory lane....

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Ian j on May 15, 2018, 01:14:30 PM
Excellent Ray. You can't help smiling when you see it starting and running.
Title: Re: A Robinson from rejects.
Post by: Jasonb on May 15, 2018, 01:37:08 PM
looks like a good un Ray, guess I will have to try and get mine running now :-[
Title: Re: A Robinson from rejects.
Post by: Dave Otto on May 15, 2018, 01:40:57 PM
Congrats Ray!
She looks and sounds great!


Dave
Title: Re: A Robinson from rejects.
Post by: fumopuc on May 15, 2018, 07:51:18 PM
Hi Ray, congrats for this runner.
Title: Re: A Robinson from rejects.
Post by: RayW on May 17, 2018, 03:39:50 PM
Thank you all for your kind words. Ran the engine again today and it started really easily and ran even more smoothly and evenly than the first time.
I am now looking ahead to the strip down and painting and debating what colour to do it. I believe that there was a mention of "Manchester Red" earlier in the thread, but does anyone know if that was the correct colour of the original engines?
One small change that I am considering making is to substitute screw down greasers for the main bearing oil cups, as I am finding that oil from the flywheel side bearing is working its way up the spokes and rim of the flywheel, making quite a mess.

Ray
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on May 17, 2018, 06:34:22 PM
Hi Ray.

It seems the beast is getting tamer!

Post number 5 of this thread ( page 1 ) shows the donor engine for the scale model painted in Manchester Red.

At the end of the day though, the choice of colour is really yours. Having seen the pictures of yours in that light Brown primer it sort of makes the engine look less heavy don't you think?

Regarding the lubrication well, they were always messy !

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: RayW on May 17, 2018, 07:00:23 PM
Hi Graham,
I rather like the Manchester Red so will probably go with that or something similar, and with the flywheel in the same colour. That should make it look a bit lighter. Most of the reds I have been looking at require a red undercoat, so I will spray everything including the flywheel with a coat of red oxide before topcoating.

Ray
Title: Re: A Robinson from rejects.
Post by: RayW on May 18, 2018, 05:02:26 PM
Beautifully warm and dry today, with almost no breeze. Just right for painting a Robinson. Got several coats of high build primer on, followed by a couple of coats of red oxide primer, which will act as an undercoat for the Manchester Red paint that I have on order. Left everything in the sun for several hours to harden off nicely
I have deliberately not tried to achieve a smooth surface (other than on the flywheel) as I like to see the natural texture of the castings. All I have done to prepare for painting is to lightly grind down any really rough projections and fill any major defects.

Ray
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on May 19, 2018, 11:50:41 AM
Blimey Ray.

This forum moves fast on occasions, I missed this one!

The paint job looks good and I for one am happy to read that you like to see the " rough " through the paint.

I'm keeping my fingers crossed that she'll run again afterwards!!   :)

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: RayW on May 22, 2018, 09:15:06 AM
You and me both Graham! A friend of mine always used to say "paint it and it will never go again".

Having got the first coat of paint on the engine, it has suddenly dawned on me that there is no provision for draining the hopper. I have looked at lots of photos on the internet and, even on the full size engines, I can't see any evidence of a drain cock.
At least our engines are small enough to turn upside down, but how were the full sized ones drained? Bearing in mind that they would usually have been in fixed installations, there must, surely, have been a drain cock somewhere.

Ray
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on May 22, 2018, 11:11:25 AM
Good morning Ray.

I've looked at many Robinson's over the years, never seen one with a tap or plug for draining.

Perhaps it was deemed unnecessary by the makers due to the environment these little work horses were placed in.

Being so compact my own engine is fixed to a fairly small wooden base that can be tipped over to drain the tank. That base was made 18 years ago and supported 103 at the Millennium N.A.M.E.S. show in the USA.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Jasonb on May 25, 2018, 08:42:46 PM
It's almost alive. :)

I can get it to fire 8-10times before it dies but that is a lot better than I was getting before.

Fitted a No3 jet just before the valve which has a 0.15mm hole so quite a bit smaller than teh 0.3mm I had drilled.

Changed one of the CI rings to Vitron

Did the blue flame test on the exhaust and only need the slightest crack to open teh valve

Still not getting a very hot tube so was holding another small torch to it as well held in one hand while flicking the flywheel with the other.
Title: Re: A Robinson from rejects.
Post by: RayW on May 25, 2018, 09:32:55 PM
Getting close now Jason. What regulator are you using on your gas bottle? I have a 4 bar one turned up full and my tube gets nice and orange after a few minutes. Did you put the cotton wool filter back in the burner? If so, I wonder if that is blocking the flow slightly. I must admit that I haven't put mine back in.

Ray
Title: Re: A Robinson from rejects.
Post by: Jasonb on May 26, 2018, 06:59:21 AM
I bought a neck tube so that I could fit the burner to my torch which has the 4bar reg and could not get any more heat out of it than when using a 2bar reg.  Catalogue does say 2bar is the max it needs and adjusting the 4bar down showed no change in the flame. Did not put the fluff back in.

Title: Re: A Robinson from rejects.
Post by: Ian j on May 26, 2018, 07:42:07 AM
They certainly test ones patience in trying to get them to run for the first time :)Could your jet be partially blocked? It's happened on mine a couple of times where the flame looks ok but blowing compressed air through the jet vastly improved it. Keep at it!
Ian
Title: Re: A Robinson from rejects.
Post by: Jo on May 26, 2018, 07:46:07 AM
This is not sounding good  :(

I might have to put my X Type on the back burner for a while: Maybe it should go in the expect problems... don't do this engine until retired pile  :noidea:

Jo
Title: Re: A Robinson from rejects.
Post by: Jasonb on May 26, 2018, 07:47:46 AM
Better hurry up and retire as you seem to be adding more engines into this pile recently :mischief:

How is that RLE comming along?
Title: Re: A Robinson from rejects.
Post by: Jo on May 26, 2018, 07:55:05 AM
Better hurry up and retire as you seem to be adding more engines into this pile recently :mischief:

I'm working on it, I'm working on it  ::)

How is that RLE comming along?

Its on the list for this week's holiday and the weather looks promising for some workshop time  :) But I might have a visit to go and see another set of castings as well  :mischief:

Jo

Title: Re: A Robinson from rejects.
Post by: Jasonb on May 26, 2018, 08:58:51 AM
Good news Jo, there is no need to retire quite so soon, looks like another reject has been brought to life (still needs a little help from another torch)

BfR1hkKSYRc
Title: Re: A Robinson from rejects.
Post by: Ian j on May 26, 2018, 09:03:45 AM
Excellent . That's running really nice and smooth.
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on May 26, 2018, 11:09:43 AM
Good morning Jason.

That's almost " textbook " running!! Well done.

Something I'd forgotten to mention to you all about the ignition tube....

You can always machine the outside diameter of it a little, if done to drawing you've got 1/16" of metal wall thickness. By reducing the wall the heat that's available has less distance to travel.

The downside is that they become more difficult to run in outdoor conditions but will fire up much quicker from initial lighting.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: RayW on May 26, 2018, 12:13:25 PM
Well done Jason. Running really nicely. Welcome to the "Running rejects club". Perhaps Graham should come up with a special lapel badge for us all!
My engine is now painted and in the process of being reassembled today, but Monaco Grand Prix practice and qualifying has temporarily halted work.
Ray
Title: Re: A Robinson from rejects.
Post by: Jasonb on May 26, 2018, 01:29:08 PM
Thanks for the tip Graham, I had thought of drilling it out a little but you mentioned that doing so would affect ignition timing and did not think of taking a bit off the outside, may give that a try as the thinner metal should heat up more easily.

Ian, I'm happy with the speed it was running at and it did not seem to want to jump about although it was clamped down, quite a nice sound too.

Now Graham what's happened to your reject? that should be finished by now as you started before all of us :LittleDevil:

Ray it's going to be a toss up between the GP and the last mountain stage of the Giro, though I think all the cycling action took place yesterday and I did not get any work done!
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on May 26, 2018, 03:37:24 PM
Hi Jason.

Well....

The simple answer is that you got the last bits of rejected castings, I don't even have a flywheel!!

The situation is being corrected as there are some being run at the new foundry, along with a small batch of Hot air, Allman, CHUK 2 and Sphinx.

For me personally I've had much pleasure from following the various builds and ultimate successes from you, I thank you all.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Tennessee Whiskey on May 26, 2018, 05:08:03 PM
Nice job old boy. And to think you did it with that Chineeseum equipment is really remarkable  8). Seriously,  :ThumbsUp: and a  :cheers:

Cletus
Title: Re: A Robinson from rejects.
Post by: RayW on May 26, 2018, 05:59:19 PM
Engine finally finished, apart from a base and a couple of greasers to replace the main bearing oil cups. Had a slight moment of panic when I reassembled everything as there was no compression and I could hear air leaking. Discovered the leak was through the inlet valve, which I removed, cleaned everything up and re-assembled, resulting in good compression once again.
I am not going to try and start it again yet until the base is done, which will not be until I return from hols at the beginning of July. Until then, I will be touring round Germany and France with my wife in our motorhome and sampling the products of the vineyards in the Mosel and Rhine valleys!

Ray

Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on May 26, 2018, 06:07:38 PM
Beautiful Ray, just beautiful!

I think your trip to the vineyards of Europe is well deserved.

Have a couple for me, Red of course, whilst you're there.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Ian j on May 26, 2018, 06:24:26 PM
Looks really good Ray, well worth all all that effort 
Enjoy your hol's.
Title: Re: A Robinson from rejects.
Post by: Ian j on June 02, 2018, 05:09:45 PM
Engine number 198 finally comes alive. Same problems we all have getting the LP gas just right! This one seems even more sensitive although it's the same set up as the fabricated engine.
 We call it low pressure but surely if we are restricting the flow by passing through a 0.15 mm jet ,in this case, the pressure is increased and the volume reduced? Just a thought

Any way here is a link to it running:-http://www.youtube.com/watch?v=c78nryotYFg

Still need to grind the inlet valve a bit more when I strip it down for painting.

Ian
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on June 02, 2018, 05:40:58 PM
Well done Ian.

Another to add to the legacy that old " HR " established!    :)

Actually the presure will remain the same both sides of the restriction what is happening is that you're slowing the time taken to reach the input pressure.   ;)

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Jasonb on June 09, 2018, 05:11:51 PM
Grahams suggestion of a smaller diameter hot tube did the trick, it now gets nice and hot and will run without an additional flame :pinkelephant: Will tweak it a bit after painting as it is missing a few times but happy that it is all working now.

QXX9fP6Iglc
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on June 09, 2018, 07:36:18 PM
Nice one Jason.

I've just come in from the workshop, been playing with its stablemate my Gardner.

Glad I remembered about the thinning down of the tube outside diameter its been a long time since I last built a hot tube engine.

We've got the 150th anniversary of Gardner's establishment coming up in a couple of weeks, the Anson is having a bit of a " do ". I wanted to get number 103 running nicely again. She's become rather clankey and I discovered that the crankpin had worn about 5/1000" down and the gudgeon pin possibly more!! My engine has done thousands of hours running over the years and I've only ever replaced piston rings.

Over the last couple of days I've shimmed up the big end bearings and made an oversize gudgeon pin and reamed out the little end bush. Quiet as a church mouse now.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Jasonb on July 07, 2018, 05:06:13 PM
I spotted No 122 at the Guildford show today. Interesting that it did not have the usual ring of holes on teh inlet valve block but an inlet at the opposite side to teh gas inlet and air flow was controlled by a small "cock" valve.

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/20180707_1038411_zpsbeyvy33u.jpg)

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/20180707_1038241_zps0se8xsnk.jpg)
Title: Re: A Robinson from rejects.
Post by: RayW on July 07, 2018, 05:59:09 PM
Back from a very hot four week tour of Germany and France and keen to get back in the workshop, but just too hot at the moment. Have been looking for a suitable wooden base for the engine and found a firm in Scotland on eBay who make wooden chopping boards in a variety of timbers and will make to whatever size you want. Have ordered a nice piece of oak which should show off the engine nicely. At least the heatwave has been beneficial in really hardening off the paint job on the engine before I attempt to get it running again.
That's an interesting variation of the inlet valve on engine 122, but I would have thought that it would make getting the balance of the gas/air mixture even more difficult as it appears that you need to adjust both the gas and the air tap instead of just adjusting the gas inlet.
Title: Re: A Robinson from rejects.
Post by: Jasonb on July 28, 2018, 02:33:57 PM
Number 202 has been sitting in the workshop for the last couple of weeks in it's new shiny paint waiting for some weather that was more conducive to starting engines.

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02934_zpsd5r8m124.jpg)

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02932_zpsjk9xo3ae.jpg)

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02933_zpszsvdfxt9.jpg)

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02935_zpsucxmbxtz.jpg)

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02936_zpsavmuwofs.jpg)

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02938_zps5rjdljyo.jpg)

Despite what one or two may say we all know that an engine is not really finished uptil it has been painted and runs. So with a drop in the temperature and the prospect of more castings arriving soon it was out to the workshop early for some flywheel flicking :LittleDevil:

nq3FptbMBrE
I'd like to say thanks to Graham for making this engine possible by providing some of his rejects and the wisdom he has shared with those of us building the X-type in this thread.




Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on July 28, 2018, 03:50:12 PM
Well done Jason.

Very nice indeed.    :ThumbsUp:

Only you and I know how bad some of those castings were, to see the engine running flawlessly and remembering the original state, number 202 is a credit to your engineering/fettling skills.

Cheers Graham.

Post Script.

I've just noticed yours and Ray's previous posts. Just looking at the engine you spotted at Guildford is that number 128 rather than 122? The picture gets a little blurry but really looks like an 8 rather than a 2. Once clarified I can give the name of the original purchaser.
Title: Re: A Robinson from rejects.
Post by: Jasonb on July 28, 2018, 04:10:31 PM
Thanks Graham

Definately 122 to my eyes
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on July 28, 2018, 04:23:36 PM
You're welcome Jason.

Most definitely 122!!

The kit was originally sold to a Mr Brian Adaway in late 1990, he became one of my " regulars " and bought many of the Alyn Foundry range.

In looking through the day book I was both reminded and discovered how I became the owner of a part built Stuart 600 gas engine. Twenty eight years is a long time!

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Kim on July 28, 2018, 04:42:20 PM
Very nice Jason!  It runs well and I love the color :)

I do have one question.  Usually people paint the fly wheel up to the rim, but leave that unpainted metal.   You have chosen to paint the whole thing.  Was there a specific reason for that?   I'm just curious.

Thanks,
Kim
Title: Re: A Robinson from rejects.
Post by: Jasonb on July 28, 2018, 04:50:27 PM
Well I suppose I can let out the secrets of what Graham and I know about the castings and why they were the rejects of the rejects pile. I may well make up a pully to go on the gear side of the crank as that is what would have been used to drive the chip chopper so no real need for a bright finish on the flywheel. You do see quite a few full size with painted flywheels and bright pullies, it's just that some people like a bit of Bling.

(http://img.photobucket.com/albums/v156/jasonballamy/Hit%20n%20Miss/Robinson%20X-Type/DSC02616_zpswf7q0exn.jpg)
Title: Re: A Robinson from rejects.
Post by: 10KPete on July 28, 2018, 07:19:37 PM
That's a beautiful engine, Jason. And it runs so well! :praise2:

Pete
Title: Re: A Robinson from rejects.
Post by: RayW on July 28, 2018, 09:08:33 PM
Beautifully done Jason and an excellent job finding a way round the casting defects. I would like to echo Jason's thanks to Graham for all his advice and encouragement to us all.

Ray
Title: Re: A Robinson from rejects.
Post by: Kim on July 29, 2018, 02:37:49 AM
Well I suppose I can let out the secrets of what Graham and I know about the castings and why they were the rejects of the rejects pile. I may well make up a pully to go on the gear side of the crank as that is what would have been used to drive the chip chopper so no real need for a bright finish on the flywheel. You do see quite a few full size with painted flywheels and bright pullies, it's just that some people like a bit of Bling.

Ah, I see.  Makes perfect sense, of course! :)
Kim
Title: Re: A Robinson from rejects.
Post by: RayW on July 30, 2018, 09:00:04 PM
Jason, Ian and I all seem to be getting our Robinsons finished at about the same time. I have now got number 197 mounted on its oak base board and just have to see now if it will run, after having been stripped down for painting and reassembled. If, and when, it does go, I will post a video.
I have also just submitted an article about the build to Stationary Engine magazine and that should appear in the not too distant future.

Ray
Title: Re: A Robinson from rejects.
Post by: RayW on August 11, 2018, 05:56:53 PM
Having had one or two fiery moments when I first ran the engine, and having now got it all nicely painted and mounted on its base, I really didn't want a recurrence of the problem, caused mainly by the poor control of the gas flow due to the very crude "needle" valve, as illustrated elsewhere in this thread by Jason.
Having ordered an identical valve to see if I could modify it to give finer control, I turned down the blunt "needle" to a 30 degree point and turned a small mushroom shaped valve seat with a 5/32" hole, which I soldered in position. I tested it out by blowing through the inlet port, with a rubber pipe connected to the outlet side immersed in water. I was able to control the flow very precisely, from nil, to a few small bubbles, to full flow, so I am hopeful that this will do the trick. It is just a matter now of swapping over the valves, then trying the engine.
Title: Re: A Robinson from rejects.
Post by: RayW on August 17, 2018, 01:32:24 PM
Gave the engine its first run today since painting and mounting on its base. Also, this was the first test of the modified needle valve and what a transformation it has made. The gas flow is now totally controllable with fine adjustment of engine speed being possible and no blazing inferno!
The engine ran really well and I should have had a video to post here, but, unfortunately, having shut the engine down, when I checked the camera it had recorded precisely 10 seconds of nothing much.
I tried to re-start the engine, but it stubbornly refused to co-operate and seems to have lost quite a bit of compression at the moment, so I need to investigate.
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on August 17, 2018, 02:36:27 PM
Good grief! Where did all these posts come from?

I must have missed them, my apologies.

Your Robinson looks wonderful Ray, very well done.

Keep us posted.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Tennessee Whiskey on August 17, 2018, 04:17:17 PM
I am with you Graham; Iíve missed two runners. Jason and Ray; both are beautiful and the videos were awesome. Congrats to you both.

Eric
Title: Re: A Robinson from rejects.
Post by: RayW on September 21, 2018, 07:59:25 PM
I am pleased to say that my Robinson features on a double page spread in the November issue of Stationary Engine magazine, as shown in the attached scanned copies.
Patrick Knight, the editor, is always happy to receive contributions for the Model Corner section of the magazine, so feel free to contact him at se.ed@kelsey.co.uk with any articles

Ray
Title: Re: A Robinson from rejects.
Post by: propforward on September 21, 2018, 08:19:23 PM
That's delightful! Getting the engine into print is just the icing on the cake really - always feels good to be published that way.
Title: Re: A Robinson from rejects.
Post by: Alyn Foundry on September 21, 2018, 08:20:36 PM
Nice one Ray!! :ThumbsUp:

I've known Patrick for many years, he and Tim " borrowed " number 103 for a year to draw folks to their autojumble stall. It also promoted sales in the Southern parts of the U.K.

It was David Edgington, the founder of Stationary Engine magazine that helped me get Alyn Foundry up and running, you've brought back many memories.

Cheers Graham.
Title: Re: A Robinson from rejects.
Post by: Ye-Ole Steam Dude on September 21, 2018, 08:34:20 PM
Congratulations Ray  :ThumbsUp:

Have a great day,
Thomas
Title: Re: A Robinson from rejects.
Post by: ShopShoe on September 22, 2018, 01:25:47 PM
Congratulations Ray.

--ShopShoe
Title: Re: A Robinson from rejects.
Post by: b.lindsey on November 28, 2018, 02:50:13 PM
Well done to both Ray and Jason on the two fine engines. Nice to see them running so well too!!

Bill