Model Engine Maker
Engines => Your Own Design => Topic started by: Ramon Wilson on January 20, 2013, 12:04:55 AM
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Hi There,
Since first registering on here last year I've found myself somewhat distracted from matters machining into another enjoyable modelling hobby namely a lengthy plastic model project. For those who may share the same interest I'll pop a couple of pics of the result on the 'Odd Ball' album a bit later.
About a couple of months or so ago I was contacted to see if I would write a build article on the 5cc 'Eta 15d' engines made previously. I agreed to do this and work has now begun on that in earnest now said model is finished. However when the Etas were made the possibilty of making the others in the series - the 15d Mk3, Eta Elite and Elite Mk2 was considered. The crankcase from the Mk3 onwards changed in that it had two protrusions front and rear to enable the fixing of a silencer and at the time the way in which that could be machined from solid was proving difficult to visualise. Thinking about it sometime later it was realised that by having a separate part inset into the case that it could probably be achieved. Working on the article then I thought what better time than now to see if that will work so the last couple of days has seen a start on the drawings and hopefully a start on the machining will begin in the next few days. I trust that what transpires over the coming weeks will be of interest to members ......
The initial layout drawing for the Mk3 was finished today..
(https://lh6.googleusercontent.com/-46QtdI1ObM4/UQhJPBv1vKI/AAAAAAAAG-s/Vu32uhvUuxM/s720/Eta%2520Mk3%2520Dwg.jpg)
....and from this a set of working drawings will hopefully materialise, that for the crankcase accomplished today too.
Back Soon - Ramon
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Hi Ramon glad to see you back, I will pulling up a chair on this one. I always learn something following you. Waiting with great interst.
Don
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A new Ramon Engine
Excellent !!
Will be watching
Pete
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Well it took a bit longer than expected but there are now sets of drawings for all five versions which, it would be nice to say having checked them a dozen times, will hopefully have minimal errors and omissions if at all - hmmm ::). - No way, found two today :facepalm:
Machining began on the crankcases today and as usual an extra case is being done in case of mishaps which means four this time. If they all come out ok I may use the spare for a fourth but modified engine and maybe actually use it as it should be - that is however a big maybe
With regard to complexity these should not be much more challenging that the previous Mks1 and 2 cases but as you can see it has these very prominent protrusions which is going to make for some interesting set ups to get to the end result. As with the Mks 1&2 however some compromise will have to be made but it should be possible to arrive at a reasonable representation of the original
To give some idea this pic is an original die cast Mk1 and 2 case
(https://lh4.googleusercontent.com/-fMoetJ8SSGA/UQg9Qsf5n-I/AAAAAAAAG-U/W5EasgJfou4/s640/DSCN2530.JPG)
And these two the Mk3 and Elite series.
(https://lh4.googleusercontent.com/-brWFTpMfEt4/UQg7-3_MjKI/AAAAAAAAG9A/fkIwKM-vqYA/s640/DSCF1479.JPG)
(https://lh4.googleusercontent.com/-nVzMOgTycLY/UQg8BXqK7cI/AAAAAAAAG9I/9Tn63JaMn9w/s640/DSCF1481.JPG)
The intention is to make the circular area above the bosses as a secondary part which should allow shaping of the bosses and the front/back of the case by milling - we'll see.
I don't feel a blow by blow machining account is apt as a lot of the images are destined for said article and as I don't want to pre-empt that too much I will just post as the various stages are reached - besides, there were plenty of images on the Tigre thread on HMEM - however if there are any questions on whats happening just fire away.
So on that note it all began like this .....
Four blocks of HE30 (6082) Aluminium each weighing 605 gms (the other blocks are for the front housings and backplates)
(https://lh6.googleusercontent.com/-4MwXYGn8Hus/UQg8DrtfTDI/AAAAAAAAG9Q/ih0vMUfxrb8/s640/DSCF1589.JPG)
And after finally making the first swarf since the Tigres were finished the day ended with the initial blocking to size and the bore for the front housing and backplate finished.
(https://lh4.googleusercontent.com/-K5lEzWl-2EA/UQl_ewbXSxI/AAAAAAAAG_E/X_9dYAN58Do/s640/DSCF1610.JPG)
The front part of the bore was opened up (this will be machined away at a later stage) and the bores proper were sized to the plug gauge made for the Mks 1&2 which will allow the drill jig to be used again.
Well there's a long way to go but that first step has been taken - just like to add that it's really nice to be able, at last, to post about something current. ;D
Hope you'll find something of interest and enjoy the journey in the coming weeks.
Regards - Ramon
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Ramon
If this is anything like the last one it will be a masterpiece!
I have pulled up the chair, grabbed a cold one and will be following along.
Dave
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looking forward to this watching with interest.
;D
Stew
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Very interesting Ramon! Can't wait to see more!
Dave
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Hi Guys , nice to see that 'one or two' of you are interested so I hope what transpires over the coming days/weeks is beneficial.
Not a great deal to report as yet but a decent couple of days machining saw the bores for the cylinders put in and the recess cut for the top plates.
Realised these top plates would need making before cutting the transfer passages so stopped to turn them up first so the passages could be cut with them bolted in situ.
(https://lh5.googleusercontent.com/-yU6pnK3KBH8/UQq5cUSBNOI/AAAAAAAAHAU/mH5vbmFgoEw/s640/DSCF1649.JPG)
Once again another small cutter was required and this worked really well plunging in sideways with ease despite the straight cut flutes. I know that some are a little wary in attempting cutter making so I post these following pics in the hope that they might help overcome any doubts. It really is quite a straight forward process and providing the cutter is not going to be used for long repetitive work in tougher steels will stand up well providing speed and feeds are kept low.
(For those who've seen it all before of course it's time to look away now ;))
After turning the profile on a piece of silver steel (drill rod) - 10.0mm dia and 25' angle - the teeth were gashed on the mill - five teeth to keep the tooth land small and the odd number to help prevent chatter.
(https://lh4.googleusercontent.com/-tbAtafYqIYg/UQq5PaOMsgI/AAAAAAAAG_k/fLkzw0tfnyU/s640/DSCF1620.JPG)
Back on the lathe the teeth were inked up (felt tip)
(https://lh3.googleusercontent.com/-W5U5awtSAVc/UQq5RdBX3pI/AAAAAAAAG_s/hg96fWUlG6U/s640/DSCF1626.JPG)
Then the teeth backed off with a needle file
(https://lh5.googleusercontent.com/-syUdH_HObrY/UQq5TprY1EI/AAAAAAAAG_0/0CCFBrajL1U/s640/DSCF1627.JPG)
Parted off the cutter was reversed and held on its shank with a 4BA bolt and the teeth undercut before heat treatment
(https://lh3.googleusercontent.com/-zCsNOrOesoM/UQq5VlSi0LI/AAAAAAAAG_8/FeaVsieibuk/s640/DSCF1630.JPG)
After H/T - which as usual for me on cutters like this, a nice bright red, quenched in oil, no tempering - the teeth were sharpened on their edges only using a well worn diamond file
(https://lh3.googleusercontent.com/-Ch6xIJIJpAc/UQq5YDP8vtI/AAAAAAAAHAE/tComSjFfmf4/s640/DSCF1646.JPG)
The cutter was a pleasure to use and the surface finish from it (no coolant or cutting fluid) on all sixteen passages was very acceptable
(https://lh3.googleusercontent.com/-5_hGN2nAlVU/UQ1njb4soaI/AAAAAAAAHAs/GMtrkAx6IMI/s640/DSCF1658.JPG)
Roughing out of the main profile has just begun - there's a lot of swarf to make as yet though as most of that block is due to disappear ;D
As always hope that's of interest
Regards - Ramon
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I just stumbled on this build. Everything looks great so far. Keep on posting and thanks for sharing.
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I've been watching Ramon.
(And you can tell by the number of views that many others are too.)
The pics of making the cutter are very interesting. I've not made any of my own cutters yet and always find these kinds of posts very helpful.
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Beautiful Ramon! Keep it coming!
Dave
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Hi Ramon,
Another one watching here, enjoying very much what he's seeing as well.
Cheers, Hugh.
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Following along also Ramon. I try not to miss any of your very instructive build posts.
Vince
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Interesting build, love the toolmaking interlude as well! I'll be watching this one.
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Vince, Dave, Carl, Steve, Hugh, Stew et al, nice to hear of your interest and your kind comments.
Yesterday was a 'sailing' day - my wife and I have recently taken up R/C sailing and very relaxing it is too besides which it makes for a good break and gets me out of the workshop for at least one day :o By eck it were a bit parky though so I disappeared in the warm for the entire day today - even doing a bit of overtime ;) the up shot being that the cases are now basically roughed out and the final shaping can begin. A few pics then to bring it up to date.
First up was to utilise the expanding mandrel made for the previous Eta's to act as a mounting spigot using a bolt and washer as opposed to expanding it. Reason for this is that due to the bore for the cylinder the mandrel is not gripping on its entire periphery. It will be okay for later ops when there is much less to come off but for roughing I considered this to be the safer bet
(https://lh3.googleusercontent.com/-L4K5Kyqw5hQ/UQ1nusZ7XvI/AAAAAAAAHBU/_T63IxlKyhQ/s640/DSCF1680.JPG)
Another angle plate was brought into play to lend support and the lower case was roughed back to the mounting lugs. The lower face of the mounting lugs was then finished and the crankcase brought to width with a larger dia cutter
(https://lh6.googleusercontent.com/-j0Kn1Tv2KpM/UQ1nqEOsEoI/AAAAAAAAHBE/IGpF3jAd5io/s640/DSCF1670.JPG)
The case was then swung through 90' and the tops of the lugs finished and the case brought to width using a 1/2 cutter that had had the corners rounded off to put a radius in the top corner of the lug
(https://lh3.googleusercontent.com/-XFtDj3hI6tk/UQ7NHOa4cxI/AAAAAAAAHB4/pZj-R0h_PV4/s640/DSCF1688.JPG)
It was then time to start reducing the weight. A thin piece was left upstanding to act as a 'foot' on the next op to shape out the exhaust boss
(https://lh3.googleusercontent.com/-F6E6r9hUdug/UQ7NNZx7kTI/AAAAAAAAHCQ/uUwrqIIgTKA/s640/DSCF1707.JPG)
So after a good days handle wringing - no power feed I'm afraid - they look like this, a resemblance of a case beginning to materialise (BTW In case you're wondering about the felt pen colour - the top rings, though interchangeable, were colour coded to keep them to their respective machined part)
(https://lh5.googleusercontent.com/-ldZ3BFJUUxA/UQ7NUfERErI/AAAAAAAAHCo/FhV7-xr-qTw/s640/DSCF1718.JPG)
Won't get much chance to do anything tomorrow but with luck the final shaping can start on Tuesday - "ah aagh Jim lad, break out the R/T" ;)
Regards for now - Ramon
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Oh Wow! You have been making progress Ramon and great work as usual. I keep learning new tricks ever time I follow one of your threads. Many thanks for the education.
Don
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Hi Don, good to hear from you - hope you're getting plenty of shop time ;)
Well after an unplanned for interlude yesterday and the bitter icy blast coming from up north today there was only one place to be and it definitely wasn't sitting indoors :D
The R/T certainly earnt it's keep today and that top profile is now complete. There was one heart stopping moment early on when that treasured Long Series 4mm end mill that survived the Tigre build caught and gave a horrible graunchy 'crack' but luckily it suffered no harm and has lived to see another build.
A pic or 'two' to bring things up to date.....
Though unintended those feet left on proved ideal for clamping down to the R/T for bringing those bosses to width
(https://lh5.googleusercontent.com/-VReEQAadwaY/UQ_8sjtbtVI/AAAAAAAAHDM/rUaWvVS3ypI/s640/DSCF1731.JPG)
The cylinder bolt holes were aligned with the spindle by using a 60 deg' pointed dowel (the bolt holes were recessed slightly so the point was aligning with a true circle)
(https://lh6.googleusercontent.com/-myom8FR_zts/URFx86wJI-I/AAAAAAAAHDo/CwYXifXpjC0/s640/DSCF1742.JPG)
After setting the stops on the R/T a witness cut to make sure everything was in the right place.
(https://lh4.googleusercontent.com/-g7fb8NeTScU/URFyB1bjgEI/AAAAAAAAHD4/TOn3kc2KwA4/s640/DSCF1741.JPG)
This was quite a time consuming op as each hole had to be set up and two cutters were used - a slot drill for roughing and that LS 4mm EM for finishing - sixteen set ups and 32 cutter changes - time to actually machine each station about 30% of the set up time ::) - but I was feeling a mite pleased when I could see it panning out as planned ....
(https://lh4.googleusercontent.com/-6zxtqmGAQAk/URFyD9GfsaI/AAAAAAAAHEA/q_X3d5kREnA/s640/DSCF1750.JPG)
The swarf pile gets bigger and it's all been cut dry. So far no cutter crowding or tooth build up - HE30 (6082) certainly is lovely material to machine
Well that's as of this evening - tomorrow sees the start on refining the rest of it.
Regards - Ramon
Regards - Ramon
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First chance I've had to read this and as always the build is looking great and some tricks to be gleaned along the way.
Ray
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Hi guys - just a short update.
Looking at them tonight it seems little advance has been made but the amount of handle turning put in certainly belies their appearance. Mainly rotary table work the 'awkward' bit has now been accomplished and theres about another four/five separate ops before the best bit begins - the fettling and polishing.
A couple of more pics .....
After milling away the feet and bringing the front and rear faces to within .5mm of finishing, the side 4 deg. draft angles were milled
(https://lh6.googleusercontent.com/-HehM41j5HyY/URQWpP1dk7I/AAAAAAAAHEs/MhOgthbrYM0/s640/DSCF1760.JPG)
The bolt holes were drilled using the jig made for the previous engines
(https://lh4.googleusercontent.com/-JrT3wUrIhoI/URVtLKcyQJI/AAAAAAAAHFU/MVDTDz6ppVE/s640/DSCF1772.JPG)
Then the 'fun' bit - of milling that relief between top and lower sections. 2mm FC3 cutters were used which were not long enough to clear - first, the corner of the case then second, the protruding boss. Ground the shanks of two cutters back to clear - short one for the main milling, the second longer one, for milling underneath the boss. Cutters were ground off hand on the bench grinder. As it happens I have just inherited a very nicely made Quorn from my good friend Sid who died last year but unfortunately there was no means to hold the cutters - but collets are on their way ;)
(https://lh4.googleusercontent.com/-Wbgx0GmY2sA/URVtPD3mXnI/AAAAAAAAHFk/-Bt4sHyMdVU/s640/DSCF1783.JPG)
What makes this op tedious is the small rib on each side between the top and lower sections otherwise it would be a simple matter of sailing right round to depth ::)
As said not looking that much different but this is them tonight along with said cutters - they do look a bit thin but no, fortunately no breakages :D
(https://lh3.googleusercontent.com/-18bFCsPBrZU/URVtRFRFdLI/AAAAAAAAHFs/mRLrgWBv_xk/s640/DSCF1798.JPG)
Next up is to radius the lower edges of those top sections
Nice to hear from you Ray - I see quite a few are following too so as always hope this is of use or interest to someone
regards - Ramon
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Very interested in your technique, Ramon. I won't miss any of this.
--Tim
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Thanks for the update Ramon, the crank cases are coming along nicely.
It's enjoyable to watch the progression on these beauties.
Dave
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Hi Dave, Tim et al
It's been a tiring couple of days with once again seemingly little advance to show for the effort ::) but I am on the home run ;D
The engine mounting lugs are now shaped and drilled and those angles on the front top edge of the lower case were milled on.
(https://lh6.googleusercontent.com/-hU8PY6njB8c/URwDpFWR3HI/AAAAAAAAHGA/wkc_L4VV68I/s640/DSCF1804.JPG)
This would give a reference for milling the angle at the sides but first the radii on the buttresses were tackled - well nearly - it was only after setting up for the next op I realised I'd missed one corner :facepalm: so that'll be another RT set up.
I still had the cutter made for the Mk1 &2 so that was something gained and the milling went okay.
(https://lh5.googleusercontent.com/-8Cv-C8XmoKk/URwDvchvxnI/AAAAAAAAHGY/ShSjU1YB0ls/s640/DSCF1813.JPG)
Once those rads were done the angles on the sides could be tackled but because of the compound angle theres no way of milling to the depth of the relief around that radius other than in steps. Due to the small cutter used even that's limited by the tool holder potentially hitting the mounting lugs so theres only one way and thats out with the needle files. I find it easier to do them one at a time - mill the angles then patiently file away the waste.
(https://lh3.googleusercontent.com/--f-ORsmRtRA/URwDzxazQtI/AAAAAAAAHGo/aBFU8QAPMXQ/s640/DSCF1827.JPG)
It is a mite tedious I guess but with care it has come out okay on the first two. Though the lower two look rather 'bitty' pre milling they are cleaning up well on the initial filing (top two) - theres a lot of fine finishing to do as yet though but that will be reasonably straightforward once this op is over. Each case is taking about an hour/hour and a half to file out as seen here.
I'm still hanging on to that last datum face on the bottom - it is still required for at least two of them - I guess those lower two angles will be the very last machining op.
That's all for tonight - like I said not much to show for the time but once these parts are done those backplates and front housings are next in line.
Regards - Ramon
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They are comming on well Ramon, keep up the good work.
J
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Hi 'guys',
Well after a relaxing but frustrating days R/C sailing (no wind ::)) I managed to finally wrap this first stage up this evening.
I really ought to admit now that when I started I did not hold out too much hope that these cases would be successful due to those exhaust bosses but 'pleased to tell' I can say I'm well chuffed with the result - they are much better than anticipated and have set me up mentally for the rest of the build.
I realised as I was filing away that if I could have held the rotary table at a 4degree angle I could probably have milled around the case instead of those steps - something to think about in future.
Heres a couple of pics of said filing, and as previously mentioned, a tedious part of the process but by relaxing into it and not trying to 'force' it to see the end result it's surprising how soon the metal disappears......
Milling as much away as those mounting lugs would allow
(https://lh5.googleusercontent.com/-Qghr4oL5CO4/UR_q27rKDDI/AAAAAAAAHG8/SxgOe-HGSy8/s640/DSCF1832.JPG)
Initial attack made with a dental burr to remove a bit more. This is a 'dangerous' op as it is easy to scar the surrounding area where it would take a lot of filing to remove the witness
(https://lh3.googleusercontent.com/-ZHrJE2LaLvA/UR_q5e06IUI/AAAAAAAAHHE/3Sbtgf-H1QU/s640/DSCF1839.JPG)
Most of this was filed away using just two needle files - a square one with one face ground off as a safe edge and the other a barret reduced at the end for 25mm or so to 3mm wide. Still quite a bit here to go though
(https://lh3.googleusercontent.com/-cffawaWy5lM/UR_q7ucpMVI/AAAAAAAAHHM/7gspIi38TDM/s640/DSCF1840.JPG)
Nearly there but still a small witness to get rid of
(https://lh5.googleusercontent.com/-BXMmOsVOk20/UR_rAGLlAcI/AAAAAAAAHHc/w8lJ0OLpXBE/s640/DSCF1845.JPG)
And finally as finished tonight
(https://lh3.googleusercontent.com/-K7hsFCtlCDM/UR_rE6jgMFI/AAAAAAAAHHs/aC9l6JQGiNY/s640/DSCF1855.JPG)
(https://lh3.googleusercontent.com/-XG3tuaW1sQY/UR_rHLtzDfI/AAAAAAAAHH0/SxS8FQWz000/s640/DSCF1859.JPG)
(https://lh4.googleusercontent.com/-nTG8MvR28PY/UR_rJWYrwnI/AAAAAAAAHH8/DkR8KzDxd9o/s640/DSCF1863.JPG)
They weigh 56/7 grams each without the top plate so by my reckoning thats 2192 gms of swarf made over the last fortnight ;D.
They'll get another final going over with Scotchbrite and Garryflex block before they get bead blasted but that won't get done until the backplates and front housings are finished.
Hope thats whetted your appetite for the rest of it to come - I shall sleep tight tonight but tomorrow will finally have to get to grips with cleaning all that swarf up before starting again ;)
Regards - Ramon
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The cases look awesome. You have every right to be "chuffed".
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They really look production quality. Very nice.
And it had never occurred to me that I could make my own safety edge on a file. I ran into that a few weeks ago. Nice tip.
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Beautiful Ramon,
Very nice attention to detail; that little rib was a bit of a problem to work around but in the end it came out perfect!
Dave
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Hi Ramon, I am really interested in the technique you use in making your engines. That is the one thing I try hard to grasp following a lot of these threads. You make things look so easy to do and I for one know it is not that easy. Putting time into a project like you do, I have no problem doing. Its to get the mind set to think things through and come up with a technique to do it. I hope with time I can get my mind set to think it through more easily. I thoroughly enjoy following your progress in hoping I can learn enough to get to that point. Thanks for you well documented thread.
Don
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The cases look awesome. You have every right to be "chuffed".
Wot Bubba said!!!!!!
Dave
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Awesome Ramon. :praise2: :NotWorthy:
Vince
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Hi Vince , the two Daves, Don and Steve,
Thanks for looking in and your kind comments. Had a really good clean up today and the ole 'shop is now 'sterile' once more ;D
I'm reminded that the house needs the same treatment so it's the 'division of duties day' tomorrow but I'll try to escape at the earliest opportunity ;) and begin to tackle those back plates.
Don, it's pleasing to hear that what I have/am posting about has some small influence on anothers thinking. I don't do it for any other reason than to share in the hope that it will help someone and, as occasion has had it, to learn from others in so doing.
For me, thinking through the job beforehand is something that is ingrained from my work and I see it very much as an important part of the whole process. By considering carefully what you are about to do and the influence that that may/will have further down the line is paramount to my way of working. Good planning should set the path for everything to follow and whilst it doesn't always work out as planned, for most of the time it does, making things that much easier all round. It's all too easy to get enthusiastic and blast into that part/casting only to find a bit later you've jumped the gun when things don't fit or are out of line. I usually begin by running through all the ops on paper in simple sketches of set ups face by face before cutting anything - it's a good way of familiarising yourself with whats ahead and if you get it wrong it's a lot cheaper on paper too :D
You seem to be doing alright at it though Don, from what I have seen of your work so far. Loved your filing rest by the way - super job. I jury rigged one when 'needs must' years ago and always promised myself something better - I'm quite envious of a very nice bit of kit :ThumbsUp:
Thanks again guys.
Back soon hopefully with some more pics - Ramon
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Hi guys, seems a while since last posting but I've been beavering away none the less ;)
Had to take a break to fix a new winch in the yacht which took longer than anticipated but apart from that have managed to make good progress on the backplates. A lot of milling in these for what they are and they aren't quite finished yet but here are a few pics....
They began as 35mm long blocks of 38 mm square HE30 Ali. First off was to bring them square and 1mm up on all faces and centre drill for the venturi position and the register on the opposite face
(https://lh3.googleusercontent.com/-rQD5Fkw-JjE/USVBhnYL16I/AAAAAAAAHIU/LbssoAUWolU/s640/DSCF1866.JPG)
The intake hole was drilled and the taper turned then the block reversed for turning the register and recess for the rotor plate. The red blocks are 6mm perspex which makes for very good protective packing.
(https://lh3.googleusercontent.com/-vGpYAVdbfCY/USVBmcfMB7I/AAAAAAAAHIk/SA63ItV9vd4/s640/DSCF1873.JPG)
Next up was to press that previously made drill jig into service and drill the bolt holes
(https://lh5.googleusercontent.com/-946siObkuDw/USVBtnVdAuI/AAAAAAAAHIs/XnFmoh8qkEI/s640/DSCF1881.JPG)
Then set the blocks up on the rotary table for milling the intake cavity.. this shows the leading and trailing edges being defined (important) - before removing the waste - (not so important). Incidentally that little Record vise is one of a pair bought for a very reasonable price then precision ground as a pair - Oh don't I just miss the use of a Jones and Shipman 1400 on a daily basis ;)
(https://lh4.googleusercontent.com/-8c8_TGMU9Co/USVBwmvgNwI/AAAAAAAAHI0/VflodPhSD1o/s640/DSCF1888.JPG)
Next up was to rough out around the intake tube then set them up in a clamp plate on the face plate for finishing to thickness and turning the taper on the intake tube OD
(https://lh4.googleusercontent.com/-qZRjrfful24/USVB2AWqAQI/AAAAAAAAHJk/7LvGzmLo8Ig/s640/DSCF1901.JPG)
With that done the plate was transfered to the R/T on the mill for roughing and finish milling the pocket in the back
(https://lh4.googleusercontent.com/-hl2-VWkmgEw/USknIvuwS5I/AAAAAAAAHKI/AdZHkjjr80M/s640/DSCF1941.JPG)
The bolt bosses were milled - note the pin for indexing rather than setting up each hole
(https://lh4.googleusercontent.com/-WcnJD-tZCDU/USpt1-_eaJI/AAAAAAAAHK4/MmS0qRDuWEo/s640/DSCF1982.JPG)
And now it's time for the fun bit to begin ::)
(https://lh5.googleusercontent.com/-1jZgdoe9xr0/USpt3--nUuI/AAAAAAAAHLA/47R8KUBvQZ8/s640/DSCF1985.JPG)
They are a little more advanced than shown here but not much so I'll leave it for now and post some more when they are finished - the angles on the sides to mill, drill and tap for the spray bar and cut a rebate in the intake tube for the bolt head left to do plus of course, that final fettle.
As usual hope that's of interest to someone :)
Regards - Ramon
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Just a quick update on these backplates which were finally finished today - a lot of milling ops for such a small part...
After a good initial fettling and smoothing with Scotchbrite and Garrylex that clamp plate was pressed into service once more for cross drilling and tapping the 2BA holes for the spray bar
(https://lh5.googleusercontent.com/-E97xrKFJckU/US1B-OcLzJI/AAAAAAAAHLg/8Z2OmObzIm4/s640/DSCF2001.JPG)
And again for milling the side angles
(https://lh6.googleusercontent.com/-aiLx-hcB8IU/US1CAr5KeAI/AAAAAAAAHLo/V5BUnWA-Qzo/s640/DSCF2007.JPG)
And yet again for milling the clearance for the bolt head in the intake tube.
(https://lh3.googleusercontent.com/-h3WQXSmGC6U/US1CK1c203I/AAAAAAAAHMI/hCx-1f8cKM8/s640/DSCF2022.JPG)
This simple little plate has really earned it's keep on these backplates and still has work to do on the front housings. An easily made and versatile fixture that possesses some extremely good workholding characteristics. They are particularly good when used for machining eccentrics too.
After another fettling they ended up like this, a result I'm well pleased with.
(https://lh4.googleusercontent.com/-PkHb0Lxvddg/US1CNQeJmeI/AAAAAAAAHMQ/jw86-HXQZvg/s640/DSCF2026.JPG)
Here's one alongside the original - not an exact copy but close enough to give the right effect I think. (The scale is only 1:1.26 but it looks a lot larger in the pic)
(https://lh5.googleusercontent.com/-VCAuBBhWp40/US1CPsGVLfI/AAAAAAAAHMY/ZTV0rISLnvg/s640/DSCF2034.JPG)
The front housings are next but I shall be taking a break for a couple of days - the first plastic model (what's that? :o Heresy do I hear you say ? :D )show we usually attend is this Saturday so need a bit of time to get ready for that - for those who might wonder, no the Crusader is not going - this time ;).
Regards - Ramon
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Beautifully done Ramon, if I my ask how much time did you spend on each part and how many setups you had to do before completing them? Only on these backplates if you care to elaborate on them. I enjoy a finish part and will spend whatever time is required to do so. Finishing is what makes it what it is. I await your next post.
Don
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Thank you Don, much appreciated.
Just been out and checked my notes - not so detailed these days since the advent of the digi camera - but elapsed time was eight days with a day and a half out to fix the yacht. Started on the 19th and finished yesterday after a day of interuptions so about 6 days total with an average of around 6 hours a day I'd guess so say 40 hrs max - ten hours a piece. I never think about this side of things now but they'd be pricey items if that was a business eh :o
They took sixteen different set ups - if it's of interest ...
1 Block to size plus 1mm on all faces and square all round (Mill)
2 Centre for Venturi/Intake postion (Mill)
3 Centre for case register and rotor pin (Mill)
4 Drill through and turn internal taper in intake (Lathe)
5 Turn Register and D/T for rotor pin (Lathe)
6 Mill intake timing pocket (Mill, Rot/Tab)
7 Drill bolt holes (Drill jig)
8 Rough mill waste around intake tube (Mill)
9 Turn intake tube and face plate to thickness (Lathe)
10 Rough and finish mill cavity in outer face (two ops) (Mill, R/T)
11 Mill bolt hole bosses - one set up but four ops each part (Mill, R/T)
12 Mill waste around base of intake tube (Mill, R/T)
13 Drill and tap for spray bar (Mill)
14 Mill sides to finish dimension 35.5 x 35.5 (Mill)
15 Mill 4 degree angles on sides - one set up - 32 ops (Mill)
16 Mill bolt head clearance in intake tube (Mill)
Hope that's not too long winded Don but you did ask ;)
I'd like to think that would have been a lot quicker were that at work but I've slowed down some - well more than some ::) - since those days ;)
Hope thats what you wanted - nice to see someones interested :)
Regards - Ramon
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Great Job Ramon! and thanks for the blow by blow!.....I appreciate that as it helps me picture how it gets done!
Damn Sexy!
:praise2: :praise2: :praise2:
Dave
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Damn Sexy huh?
Hmmmm, well - I never heard muh work described like that afore but I guess whatever rocks ya boat Dave ;D
Ah, you're welcome mate - at least Don's not on his own ;)
Ramon
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Damn Sexy huh?
Hmmmm, well - I never heard muh work described like that afore but I guess whatever rocks ya boat Dave ;D
Ah, you're welcome mate - at least Don's not on his own ;)
Ramon
Don't get me going over polished brass!..... 8)
Dave
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Thank you Ramon, it is always good to know that such fine work is not with out paying the price of time. The blow by blow was not too long and I take notes here. For the ones just starting as I am, this gives me some confidants. I know I am not along putting in a lot of time making a part. I see people post things and not really knowing what was evolved in making them. I am sorry if it took some of your time here and very grateful that you did.
Regards Don
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Like the look of this Ramon, a great start, lovely machining.
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Hi Don, Thanks for your kind thoughts, but as with Dave you are more than welcome.
I'm more than happy to spend the time to help anyone interested enough to ask. Posting on here - for me - is all about sharing with others of a similar mind and interest. I could be in two local model clubs but I choose not too predominently because of their main interest is in running locomotives. I have good relations with members of both but would much rather 'meet' people on here on a daily basis rather than once a month. Besides, I've spent a lifetime in clubs and always end up with too much to think about as well as the modelling - I made a promise to Sue that once I retired I would 'serve' no more ;) so I see this and HMEM as very much my substitute for being in a ME club.
Where individuals skills are concerned, small or great, I believe it's all relevant to what we strive to do. Whilst aware that there are those with less skill on here I try never to lose sight of the fact that there are many out there with far far greater skills than I possess or indeed am likely too so we can all learn from each other at what ever level. When I flew control line models there was a well known American modeller who had a great phrase for this and that was "Theres room in the hobby for everybody" - can't say fairer that that eh :)
Today I spent getting ready for the model show on Saturday. I had decided to hopefully off load some of my kit 'stash'. It's all been quietly sitting on shelves and in cupboards here and there but boy when it all comes out it really hits you how foolish you've been expecting to be able to acheive it all. A real question of 'dream on' I guess but reality certainly struck home today :o Hopefully I won't have to bring it back home again ::)
Thanks for your thoughts Nick - with luck some more next week
Regards - Ramon
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Ramon
Attentively following you along. :praise2: :praise2:
I had decided to hopefully off load some of my kit 'stash'.
I hope you will not start missing your stash in a month's time. :'( I know I would.
Vince
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Oh I guess I will at some stage Vince but there's 'being realistic' and 'being realistic' :o
;D ;D ;D
Ramon
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Still watching Ramon.
Sorry I don't say much. I struggle to have something meaningful to say.
I really like the work and the finishes you achieve.
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Hi Guys, a quick update on a bit further progress.....
A good start has been made on those front housings. Now that theres a fourth case to use I'd like to make the extra one a little bit personalised but based on the 'Elite' version so theres one Mk3, two Elites and one Elite Mk2. The Mk3 is basically turned to profile with the Elites much the same but with a small amount of R/T work and the Elite Mk 2 with its prominent boss underneath having to be milled to shape. Here are a 'few' pics........
Done at the same time as the back plates the basic blocks were milled square and brought to dimension plus 1mm on all faces. First op was to bore the housing for the main bearing, turn the outer diameter register to a nice slip fit into the case - The housings were turned to .005mm down - well as near as I could tell using telegauges - which will probably expand the outer slightly when the bearing is pressed in so they should have a nice snap fit. The inner 10mm bore was drilled, then bored before reaming to maximise concentricity
(https://lh3.googleusercontent.com/-V2edDtTS_hE/UTTtO67z4RI/AAAAAAAAHM0/d4R1F_pOMNM/s640/DSCF2037.JPG)
A chunky fixture was turned up to hold them for turning/milling the outer profiles.
(https://lh6.googleusercontent.com/-PqdoV4n05cg/UTTtTyuaE6I/AAAAAAAAHNE/bplFn-wnDy4/s640/DSCF2053.JPG)
Thinking ahead a bit too quick this one was roughed before I realised there was a prior op to do ::)
(https://lh5.googleusercontent.com/-8ElEvHBZvWA/UTTtWSy3jRI/AAAAAAAAHNM/wxy75qoRW4s/s640/DSCF2055.JPG)
Which was to mill the internal lightening pockets... (Not exactly essential, these are cast in to the original die casting so they were put in for the sake of replication) ;)...
(https://lh3.googleusercontent.com/-RWGoG3xuIHo/UTTtY6_LYxI/AAAAAAAAHNU/SVMsunkyAu4/s640/DSCF2059.JPG)
First stage complete ready for those front profiles
(https://lh3.googleusercontent.com/-0g_YFTcXcbs/UTTtbSmJvII/AAAAAAAAHNc/ClzUdO1jdbM/s640/DSCF2065.JPG)
This is one of the two Elites. The Mk3 has a single taper back to the face
(https://lh5.googleusercontent.com/-axhCs4obAqE/UTTtgIc0sYI/AAAAAAAAHNs/w8MEP7Xnb5o/s640/DSCF2072.JPG)
The set up to mill the Elite Mk2. This is the first real use of the dividing head as a 'rotary table' in shaping
(https://lh3.googleusercontent.com/-m1t8GREwqC8/UTTtiR5J7LI/AAAAAAAAHN0/b8z3pRNNCtk/s640/DSCF2075.JPG)
Initial roughing with a 6mm FC3
(https://lh3.googleusercontent.com/-A7R7pydpQ7s/UTTtkwk_YuI/AAAAAAAAHN8/H1d3YI4cDpM/s640/DSCF2079.JPG)
Final cuts with a 3mm with the corners radiused by hand on the offhand grinder
(https://lh6.googleusercontent.com/-gPRJzzL5c6I/UTTtnX-Yt5I/AAAAAAAAHOE/3Bwewefhe-Q/s640/DSCF2085.JPG)
'Early days' as yet but a promising start..
(https://lh4.googleusercontent.com/-L5bZd52eRWI/UTTtxWBuCkI/AAAAAAAAHOk/JEnERUmeo84/s640/DSCF2093.JPG)
And this is the current state of play as of tonight
(https://lh5.googleusercontent.com/-6vq4aeL6go4/UTUqOoRlS9I/AAAAAAAAHPk/IFqQQzH3ze4/s640/DSCF2099.JPG)
Things may slow down a bit for a few days as this raw weather looks set to break tomorrow so if so it's garden time - I have no more excuses left ::)
There really is no need to say sorry Carl - it's nice to know you are still following. I'm sure you're not alone :)
Well 'that's it for tonight folks' - now if it would just rain tomorrow ;D
regards - Ramon
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Fine bit of whittling there Ramon! I'm diggin it!
Dave
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Dave,
Diggin sounds like what Ramon is going to be up to for the next short while. I hope he gets the garden in order because I'm really enjoying his beautiful work!
Dave
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Still enjoying your art here Ramon. I hope you get your gardening done pretty quick.
Don
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Hi Guys - good to hear from you :)
Though I did spend mostof the day in the garden yesterday I did manage to get a couple of hours in the workshop before the Sun warmed things up :D
Those front faces of the Elites have raised portions where the bolts go so to mill them to the angle of the taper would require a couple of special cutters making.......
The satisfaction of making a cutter that works successfully never fails to satisfy - personally I find it a very rewarding part of what we do. It's not difficult and a skill well worth acquiring. Don't be put off if you've never tried, the first probably won't be that brilliant but every one after will improve, without a doubt. Apologies then for repeating this if you've seen it all before - hopefully however this will help someone somewhere.
First up then was to turn some 6mm silver steel to 5mm diameter for clearance and put on the relevant taper - 18 and 25 degrees. The end was drilled 1mm as these would be end cutting as well as on the side (the card was to help stop the camera focusing on the background). The flutes were milled with a 3mm cutter and the teeth backed off using a needle file
(https://lh3.googleusercontent.com/-sytk5FDp_6o/UTe1cUtWg0I/AAAAAAAAHP0/BnT4R-Ch8S0/s640/DSCF2120.JPG)
(https://lh6.googleusercontent.com/-uZB_sSgMVOo/UTe1ejLUQ7I/AAAAAAAAHP8/RnrZpuQVGGg/s640/DSCF2122.JPG)
(https://lh4.googleusercontent.com/-mJCfGOlfG3A/UTe1ju0q-fI/AAAAAAAAHQM/tJjq15oEH2k/s640/DSCF2134.JPG)
I like to hold the blank in the lathe for filing the teeth using the bull wheel for indexing to give better control over the angle
(https://lh5.googleusercontent.com/-Cxzhxih45mQ/UTe1lpgD0zI/AAAAAAAAHQU/8lVP2xOu0hE/s640/DSCF2142.JPG)
Backed off and the ends profiled and radiused
(https://lh6.googleusercontent.com/-7OTNogadd20/UTe1nxy3iLI/AAAAAAAAHQc/4V77KoRfndA/s640/DSCF2149.JPG)
Heat treated - no tempering, the colour is from the heat treat, only the cutting ends are hardened - the teeth were touched up with a well worn diamond file to sharpen them
(https://lh6.googleusercontent.com/-uR9IymwpBCg/UTe1qtlgUYI/AAAAAAAAHQk/kIN6njYHG64/s640/DSCF2161.JPG)
And a test cut made to check if they would cut - the rough edge on the R/H side is where the cutter was tried on the end before trying the side
(https://lh6.googleusercontent.com/-CxRkXeke0x4/UTe1syb794I/AAAAAAAAHQs/lvMRVMV58IY/s640/DSCF2164.JPG)
First up was to remove the waste with a 3mm long series cutter then flare the taper in using the tapered cutter
(https://lh4.googleusercontent.com/-klEzjwPqy6w/UTe1xofCxxI/AAAAAAAAHQ8/imK5djut4vY/s640/DSCF2173.JPG)
Then cut the recesses
(https://lh4.googleusercontent.com/-_Sye57S_lq0/UTe10G8U6SI/AAAAAAAAHRE/U_O1Zm-gM8c/s640/DSCF2176.JPG)
So far so good but now it's time for the fun part to begin ;)
(https://lh4.googleusercontent.com/-sojqpEaKpUQ/UTe12qH6wUI/AAAAAAAAHRM/f7WrSfo0wE4/s640/DSCF2181.JPG)
(https://lh4.googleusercontent.com/-WkwfVs256Cw/UTe143aVzlI/AAAAAAAAHRU/RIodn7_MtF8/s640/DSCF2186.JPG)
And here's the state of play this evening after cleaning up the corners near that protrusion and an initial smoothing. That protrusion still requires machining along with the outsides and the corners radiused and there's still the other two Elites to do the same as yet - it'll be a while yet then
(https://lh3.googleusercontent.com/-ckkD_bsTrSs/UTe17EcHZ_I/AAAAAAAAHRc/stGuvWQWNP0/s640/DSCF2191.JPG)
That protrusion actually serves no real purpose ::) On the original Mks 1 to Mk 3 there was a degree of sub piston induction. The introduction of the silencer on the Mk3 saw this having an effect on performance so a 'solution' on the Elite was carried out by having a port through on the underneath of the front housing picking up with a corresponding hole drilled in the crankshaft - just as for front induction but for the sole purpose of sub piston induction. Apparently this was not that successful and was dropped - the hole no longer drilled in the crankshaft but the front housing remained the same - I can only assume the hole was cast in. The Elite I was loaned for copying has this feature.
The workshop now has another layer of ali swarf not least from blowing it out of those deep pockets a day or so ago - I tried to contain it at first but just gave up in the end - Sue's really impressed with the little bits of glitter that keep appearing in the carpets :). Those visitors who usually remark on how clean it is should see it now :o
Regards for now - Ramon
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Comming on well Ramon and looks like the weather forcast is for "workshop time"
J
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Morning Ramon,
It is nice to see you providing details of some toolmaking. I am guilty as I have had a cutter grinder for 15 years and have never really taken the time to learn how to properly use it :shrug:.
I know the problem with the lure of the garden, it is so lovely at this time of the year with all the snowdrops/daffs coming out. It will only get worse with the joys of planting up the seed trays and watching them grow ;D. I never find the spring very productive in the workshop.
Jo
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Been catching up on your thread Ramon, must say it is very impressive
Steve
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Ah...it took me a couple of reads to understand 'backing off the teeth' but the photos say it all.
Thanks for that post. Very helpful.
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Glad that's of some use Carl - I hoped repeating the showing of making of small cutters like these would be worth while for someone .
Jo, I had a Clarkson T&C for many years - I only ever used it the once to reduce a 12mm end mill in diameter. It just sat there gathering dust during my several year layoff from ME. I sold it on a few years back but recently was beginning to see that as a potential mistake given the revival of interest. However, my good friend Sid who passed on last year requested that I should be the 'guardian' of his Quorn. So now I too have to find out 'how it works' - at the moment though it's just quicker to get out the needle files.
Looks like you're right Jason, one day of sunshine and we are back to good old East Anglian 'clag' (grey featureless sky) and a cold easterly wind - only one place to be then, and the greenhouse it aint ;D
Regards - Ramon
Edit - Ah, I meant to say Steve, hopefully at the end of this I shall have four engines but nine, all in one lump, now that's impressive :ThumbsUp: :ThumbsUp:
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Hi 'Guys'
Well the crux of this build is well and truly over I'm pleased to say ;D - All the case parts have come off successfully without any untoward mishaps this time so I definitely have the makings of four engines :)
After milling the relief around three of the front housings....
(https://lh6.googleusercontent.com/-Y7jfRAj6H8o/UT0KkFK8wwI/AAAAAAAAHRs/N5IDN7riZcc/s640/DSCF2201.JPG)
....They were set up and the front bearing housing rough bored (this helps keep any stresses on the mandrel used later to finish turn them to a minimum)
(https://lh5.googleusercontent.com/-LB9CtNZ4P6k/UT0KmoC9q5I/AAAAAAAAHR0/4m0SVBq_S1s/s640/DSCF2203.JPG)
Then the final milling op to mill the angles....
(https://lh5.googleusercontent.com/-wAJyuo2uY7Q/UT0Kr-yg1nI/AAAAAAAAHSE/p_CZ3Lx5p6M/s640/DSCF2212.JPG)
....Before turning a close fitting expanding mandrel....
(https://lh5.googleusercontent.com/-SolYc7pi8IY/UT0KuY4uYaI/AAAAAAAAHSM/ZTnsMNL_pcs/s640/DSCF2215.JPG)
....to hold them for finish boring the front bearing housing.
(https://lh6.googleusercontent.com/-h07Aoz9NDyU/UT0Kw0Glk_I/AAAAAAAAHSU/3mLIRJzShWo/s640/DSCF2222.JPG)
The main/rear bearing housing registers on the larger diameter - a nice slide fit with no shake - and pushed back tight onto the face. The expanding part is just .01 down on 10.00mm. A very light nip of the screw is all it takes to hold it sufficient to turn the .5mm left on diameter and rear face of the front bearing housing. This op is one that has to be done with as much precision as can possibly be achieved as the bores for the bearings need to be truly concentric and in the same plane. I have found that using this method provides the most consistent results to achieve this requirement within the limited equipment available.
That 'protrusion' was finish milled and the induction hole drilled part way through to replicate the original. As the crankshaft is not going to be drilled to suit it was felt there was no need to drill all the way through and risk possible air leakage.
The corners were radiused by hand filing and all parts given a final going over with fine 'scotchbrite' type abrasive materialand finally they are finished .....
(https://lh3.googleusercontent.com/-m_iC5eRcgqY/UT0KzVDM8OI/AAAAAAAAHSc/S_tNY2eiVSw/s640/DSCF2226.JPG)
(https://lh6.googleusercontent.com/-qIltnBbOPSE/UT0K145dcJI/AAAAAAAAHSk/8dDvwEQnvdk/s640/DSCF2229.JPG)
Though they may look a bit 'polished' these parts will all get bead blasted at some stage which will provide that nice uniform matt surface to even everything out.
Cylinder heads, and prop drivers next which will see the end of the ali machining but I have to take a few days out at this stage to catch up on something else that requires attention before next week. Back as soon as that's all fixed then.
Regards - Ramon
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Hi Ramon, just catching up on your build. I am grateful for showing how to make the cutters. The engines all look so professional and remarkably identical. I really hope one day I can achieve such professional looking models. Excellent work as usual and looking forward to your next post after your endeavors.
Don
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Very impressive Ramon. The family shot looks fantastic :ThumbsUp:
Steve
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Fantastic work Ramon.
I have noticed that when making these small engines you never make one but more than one. In this case you are making 4. Do you do this just in case one is scrapped then you do not have to start again from scratch?
Vince
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My experience with aero engines is that their life expectancy is approximatley one flight and then I am picking up the pieces :Lol:, so best start prepared with a couple of spares :ThumbsUp:
Jo
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Superb work Ramon, your hand finishing is excellent.
Paul.
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Ramon, not only are the parts beautiful, but that is one superb finish on the also!! Still enjoying your build very much.
Bill
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Hi Guys, Thanks once again for all your kind comments, all very much appreciated.
I have noticed that when making these small engines you never make one but more than one. In this case you are making 4. Do you do this just in case one is scrapped then you do not have to start again from scratch?
Vince
Vince - you are correct in assuming that. When I first set out making an engine (the Nova 1) I made just the one and as the case began to have more and more work put in all the old feelings from work leapt to the surface - the more you get done the more there is to lose if you make a boo boo (polite phraseology for something quite dissimilar ;D) When the next project was tackled I decided to make two cases for the very reason you state and though I did make a mistake it was recoverable and I ended up with two useable cases and so two engines. So far, on three further builds including this one, that's been the result too :)
Regarding the finish Bill and Paul, I think I should point out this is not an attempt to make them 'shiny' but more to eliminate any tool marks as bead blasting will not cover up any defects. With regard to how they will look like these are the case parts for the Mk1 and 2 Eta's after blasting...
(https://lh6.googleusercontent.com/-K6vFDZjSBsY/TdgvKrgDpoI/AAAAAAAAFI4/nKXFSkiHGuI/s640/DSCN3147.JPG)
and to give some idea what hopefully these will look like these are the Mk1 (left) and 2 as finished
(https://lh4.googleusercontent.com/-2k5q1aNPn4A/TgjqDKXvP_I/AAAAAAAAFT0/JtnUFnA0XSk/s640/Ano%252008.JPG)
The Mk 3 will be a similar blue head to the Mk 2 (there is little difference 2 to 3 save the crankcase exhaust bosses and the circular top to take the sliencer), the Elites with gold heads and prop drivers and the Elite Mk2 plain aluminium. (Well that's the plan ;))
My experience with aero engines is that their life expectancy is approximatley one flight and then I am picking up the pieces :Lol:, so best start prepared with a couple of spares :ThumbsUp:
Jo
If you are picking up pieces of engines after one flight Jo then I think you might have got something a bit wrong :o for after a near lifetime of messing with these little wonders of engineering I can only remember one severely damaged engine - I managed to push the crankshaft through the backplate ::)
For those who may be interested amazingly even this one survived unscathed from a near vertical impact on tarmac though going by the impacted spinner material in the hollow prop nut the spinner acted like a crumple zone. (It ripped the engine right out of the airframe though - it lies top right - and one of the prop blades flew past my head some 62 feet away where I was standing in numb disbelief)
(https://lh3.googleusercontent.com/-0WN3Sm1wz4w/TEmBA5WmKQI/AAAAAAAAFiI/eOwSAp6gWYQ/s800/Oriental%2520crash127-2.jpg)
Typically this was in competition and was a particularly well flying airframe. It's replacement simply wasn't in the same ballpark so this was a bitter loss and a big setback. There should be a smiley for gutted! The crash was caused by control failure - I had been given some 'genuine duralumin' which turned out not to be so. The bellcrank pivot hole had opened up to such an extent the bellcrank slipped the bolthead :o.
The engines being built are not intended for an airframe though I have thought about scaling up the respective style of model for this extra Elite - thinking about it and doing it of course being two totally different game plans ;)
Hope this little diversion is of interest to someone
Regards - Ramon
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OOPS! That'll take more than a lick of paint!
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Like I said somewhere previously Tel - 'You're a man of few words but much wisdom' ;) - You've certainly nailed this one :D
Ramon
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Oh Man Ramon....that looks like it hurt bad! .....The engines are beautiful though!
Dave
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"If you are picking up pieces of engines after one flight Jo then I think you might have got something a bit wrong"
Or as the saying goes..."if at first you don't succeed, skydiving may not be for you!!"
Bill
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I only did it once, I blame a poor instructor. ;D
Jo
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Jo,flying models or skydiving?
Eric
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I got put off sky diving/parachuting when a lass went through a set of helicopter blades where I was considering having my first jump. :shrug:
And as for my instructor for flying model planes I was jumping to assumptions because having only flown once I got introuble for smashing up the plane. Mind you he never used to come home until he had also smashed up one :ROFL:
Jo
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Beautiful work Ramon. For smallish diameter cutters such as these, do you prefer a certain type of tool steel (meaning Oil vs Water vs Air hardening)?
> First up then was to turn some 6mm silver steel to 5mm diameter for clearance and put on the relevant taper - 18 and 25 degrees...
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Hi Peter,
I usually use nothing more than silver steel or gauge plate (GFS) and always quench in oil despite the recommendation that silver steel is quenched in water. This comes from a work background heat treating and precison grinding many small parts on a weekly basis. It was found that when some of the Sil St parts were quenched in water there was occasionally a degree of brittleness in the parts that was inconsistent and difficult to pin down. Quenching in oil cured that problem without loss of hardness so have done that ever since.
Apart from this oil quench on SS, heat treatment was carried out to manufacturers specifications in proper heat treat ovens - Wild Barfield - and the one thing that was immediately apparent when these were used for the first time at the correct temperature (850F for GFS if I remember right) was the distinct lack of 'redness' as the parts were removed compared to what parts were usually taken too previously when flame hardening by hand. Since then I'm always careful not to overheat the material - just a nice bright red is quite adequate to get the hardness for small tools such as described without brittleness bearing in mind I very rarely temper them. My main reasoning about not tempering is that they are very unlikely to be used over the long term and the extra hardness is a trade off to potential brittleness. So far - whilst tempered cutters have failed mainly by wearing - I have experienced very few cutters breaking in use.
That said these cutters - made for cutting the Bentley cylinder heads fins were a bit of a mixed bag but there was a lot of cutting to do. I made the three on the left (all identical) first. The first cutter went competely on the first fin slot ::), the second did about one head if I remember rightly but the third did all the remaining heads losing first one tooth then the second then merrily flycutting it's way before finally going with half a head to go. The fourth cutter was made to finish that head off ....
(https://lh4.googleusercontent.com/-Z8zNT_boWJw/TPVxEASKKuI/AAAAAAAAFig/CEgN0ZB5MoQ/s640/DSCN2705.JPG)
....and the last cutter being longer to get to the central fins slots
(https://lh5.googleusercontent.com/-1zCyB_qnUSE/TPVw3Q_OgEI/AAAAAAAAFig/2oiD5bPdX84/s640/DSCN2686.JPG)
One thing noticed very quickly was that as I don't have coolant set up on the mill brushing coolant on in the usual fashion soon led to the cutters clogging quickly leading to tooth breakage - that third cutter was used dry and certainly carried out most of the work. (material was En1a BTW)
Hope that helps and is of use.
Regards - Ramon
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Beautiful work Ramon,
The group shot of the crankcase parts is just wonderful; I also appreciate you taking the time to show your cutter making. It is a skill that I hope to improve on in the future.
When doing the backing off of the cutter teeth how much of the original profile is left? On the one or two that I have done it has just been by eye; and I left maybe .02" or so.
Also do you stone the face of the cutting edge or what is left after the relieving the teeth?
Thanks for taking the time (and pictures) so keep us up to date.
Dave
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Hi Don, thanks for your kind comments - much appreciated.
Personally, I find taking the time to post something is well worth the effort if someone gets something from it even if it's only a minor thing - the nice thing is that it can be done on a daily basis :)
Re the backing off - having inked up the still unhardened blank I usually file into (toward) and over the cutting edge trying to leave just a witness of ink on the line of the cutting edge. This way any burrs are behind the cutting edge. Care needs to be taken not to hit the next edge in line. Depending on the cutter however sometimes the backing off has to be done with a hand power tool and a rotary burr or grinding tip.
Once hardened I touch up the edges with a diamond file as shown only stoning the faces after if the very edge appears rough. As at this point everything is so close to the original blank it's very easy to overdo it and lose the profile if it's a shaped one so I like to keep this to a minimum. If the cutter rubs (insufficient backing off) or doesn't cut at all then this concern tends to go out of the window as more is ground away.
These three cutters were made for the Racer liner ports. One of the liners was made from cast iron the other a from very tough high tensile steel The first two were tempered and just wore on the HT steel without really doing any cutting - caused more by the lack of backing off than the tempering. The third having been heat treated but not tempered was backed off by hand on the off hand grinder and simply sailed through.
(https://lh5.googleusercontent.com/-ieREzeTVZxc/S9dYc08u2UI/AAAAAAAAFiw/hhG6xGbWIM8/s640/DSCN2311.JPG)
I've made a fair number of cutters over the years but still find I'm learning something near every time I make one but the process is easy enough - it's certainly not a difficult one to accomplish with a bit of care so I hope this discussion will encourage others to have a try.
Regards - Ramon
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I've made a fair number of cutters over the years but still find I'm learning something near every time I make one
And I keep learning every time you post a new picture! :)
For the last set of 'saw blade' looking cutters you posted, it looks like they are kind of modular & attached to a standard tool holder stub (as opposed to the all-in-one style machined from a solid blank). How do you attach & fix these cutters on the shank stub? I see the main hole but no other keyway type slot or pin hole. About what diameter are those? And looks like you have machined in some relief so the teeth stand proud to the main disc body?
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Hi 'Peter',
Yes these cutters are held on a mandrel using a 2 BA or similar sized metric cap head bolt. There is no keying just the torque of the bolt resisting the cutting forces which so far has proved more than sufficient for the task in hand. Keying or pinning is not a good idea for this type of cutter or indeed thin slitting saws particularly if power feed is being used (I don't have that facility) - as if the cutter jams it usually means a shattered cutter whereas these can at least slip - even so, still doesn't give you much time to stop the power feed if it does though :o
(https://lh3.googleusercontent.com/-PpWnIEA6dXk/S9dYaOtvTrI/AAAAAAAAFiw/ELzxfYd2xwE/s640/DSCN2304.JPG)
You are right in that these cutters were dished out to the periphery in an attempt to provide a degree of backing off without the need to carry that out as a secondary op. The cutters, which are 22mm diameter, are only 2.5mm thick so the amount of dishing (both sides) was minimal in order to keep some strength in the blank. The image shows them before use but as already said they rubbed like hell and soon degraded - lesson soon learnt there then ::).
Providing there is sufficient room for an adequate caphead to hold it tight enough I now prefer to make small removable cutters such as these and those made for recent builds rather than machine them from one piece. This one is held with a 4mm bolt. The block in the background BTW has the 'test' cut in it
(https://lh3.googleusercontent.com/-txz-AbR0PL0/T6mJtFhBhBI/AAAAAAAAF_8/KH6CwnmSx-g/s800/G32%2520032.JPG)
Hope that adds a little more for you and anyone else interested Peter
Regards - Ramon
PS Should be back on the build by the weekend ;)
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Hi guys, I got back onto the engines today and have made a good start on the cylinder heads.
One of the reasons I took a couple of days out was that last night I was invited to talk about the engines made so far to members of the Halesworth MES and needed some time to prepare for it.
I'm really pleased to tell you that I had a thoroughly enjoyable time, was warmly welcomed and somewhat mildly surprised but very taken indeed to see that what are predominently locomotive and traction engine minded members take such an interest in these little engines and their manufacture :)
It was also rewarding in not only the doing, but, in describing the way that conrods are held for turning, came away with a priceless tip for holding fish bellied rods for further machining as well as a very nice gesture from a complete stranger of a gift of a Russian made engine.
Back soon with some pics of current play ;)
Regards - Ramon
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OK
The tip regarding the fishbelly rod.....?....pictures and description please!
And a Russian made engine......now I don't need to ask about that do I?....... 8)
Dave
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Gimme time Dave - all will be revealed ;) ;)
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Hi guys, - just a quick update. The cylinder heads were finished off today - just basic turnings but here's the sequence if it's of interest
First off was to part off some blanks and bore them. The Mk3 and Elites are blind bores with a slide fit over the liner. The Elite Mk2 had fins shrunk onto the liner so this was made a tad undersize and has a separate head. there was a spare liner left over from the Mk1&2 build so this was used as a plug gauge for the three and will have the fins shrunk on to it at a later stage before lapping.
(https://lh3.googleusercontent.com/-0E-rgVi6fMA/UU-HoOsz1II/AAAAAAAAHTs/YNVukGOgtO8/s640/DSCF2247.JPG)
Held on another freshly turned expanding mandrel the first three were faced off to length to a stop then the ODs finish turned.
(https://lh3.googleusercontent.com/-dMXFj5-dNP0/UU-HqtAJQfI/AAAAAAAAHT0/ofVpDkmKFT0/s640/DSCF2249.JPG)
The next op was to drill them through and counterbore the holes for the head bolts. It was found on the last engines that the drill tends to wander far less when drilling from solid than through precut fins plus it's much easier to debur the holes in the fins done this way.
(https://lh3.googleusercontent.com/-SsXzQgnLVf0/UU-HtBr7IoI/AAAAAAAAHT8/XsZXix1OnAU/s640/DSCF2255.JPG)
The top angle was turned then the fins cut with a 2.3mm wide grooving tool ground from a FC3 cutter shank. Drilling and tapping for the comp screw was the last op.
The expanding mandrel was then reduced a thou or so by filing and polishing to accept the Mk2 fins and these were drilled through. Another grooving tool, this time 1mm wide was ground up and the fins gingerly cut, depth of cut on all heads was 5.1mm. Despite a bit of vibration with the interupted cuts as it passed the drilled holes this thin tool held up well.
(https://lh3.googleusercontent.com/-alKCBLCjz_I/UU-HvtYt0_I/AAAAAAAAHUE/AQGdMBJWwao/s640/DSCF2265.JPG)
Last off was to make the head to suit. A blank was set in the soft jaws and the base and a 1mm register to fit the fins turned before reversing and taking out the deep groove - another 'FC3' tool bit being ground up for this. The holes were drilled and counterbored and then the eight cooling holes drilled .....
(https://lh3.googleusercontent.com/-H0AD0-ofzSY/UU-Hx9WYV2I/AAAAAAAAHUM/2rhuHFAMo-4/s640/DSCF2269.JPG)
It's been quite a while since this little gizmo was used but those holes (48 divs) in the chuck came into play on this op
(https://lh6.googleusercontent.com/-Mnhlt9785MQ/UU-H0GZKxcI/AAAAAAAAHUU/JFMoKbNZfyE/s640/DSCF2272.JPG)
The two parts for the Mk2 head .....
(https://lh3.googleusercontent.com/-Wfb4PceW1VM/UU-H2RiardI/AAAAAAAAHUc/JJHtsPpIawQ/s640/DSCF2278.JPG)
..... and all heads finished ready to fit
(https://lh6.googleusercontent.com/-lz8im3leN3Q/UU-H4hS4Z3I/AAAAAAAAHUk/EJhtza__Ozo/s640/DSCF2284.JPG)
Well that's another stage done, I'm waiting for some ali for the prop drivers and prop nuts which should hopefully be here in a couple of days so in the meantime I've cut off some tougher ali for the con-rods. With all the ali out of the way it'll be time for a good clean down before tackling the steel bits.
Regards for now - Ramon
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Hey Ramon,
Nice!
I like the indexer....I plan to put the same thing on the back of the SB...
Dave
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Hi Ramon, another great job on your engines. You have a tendency of making it all look so easy. I also like the indexer on your Myford. I have one that takes advantage of the tapped hole on the back side of the lathe behind the Chuck. I have attached a photo of it. I haven't drilled my chuck yet I was wondering what number holes would be the best combinations?
Don
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Hi Ramon,
That indexer is a much better version of one that I was thinking of making, for exactly the same purpose that you use it for! Just one thing has been slowing....well stopping progress. Do you use any form of brake or clamp to stop the spindle chattering, or is it all down to a good fit of the detent pin??
As always your threads are fantastic, very informative. Keep it up!
cheers
Bill
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Looking great Ramon
Always nice to see some indexing and drilling spindle action on the lathe. I like your idea about removable heads on the home made cutters too.
Steve
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'Morning guys, Thanks as usual for your input and comments.
Re the number of holes Don, I guess it depends on the most likely use. In the early days this was the only form of dividing I had.
Using a cross slide milling attachment held vertically to a piece of thick GFS itself bolted to a vertical slide I was able to (rather precariously I might add ::)) mill away an area on which to mount a detent plate
(https://lh4.googleusercontent.com/-imlpwc5l2tE/T9zrzcBOjdI/AAAAAAAAGaA/UfsjSCkNt5Y/s640/DSCF0487.JPG)
(https://lh4.googleusercontent.com/-DySH6Nz8SHs/T9zrwPJXWmI/AAAAAAAAGZ4/1CdU7mJksvs/s640/DSCF0484.JPG)
The limitation of 60 teeth was what lead to the holes in the chuck - 48 and 50 divs to fill in some of the gaps.
Bill, for plain drilling or counterboring I haven't found it neccessary to have some kind of spindle lock. If milling is carried out I put the lathe in low gear on the pulleys - not backgear that is - and keep the drive belts tight and the clutch engaged. Can't say I have ever noticed any movement.
When the Bentley first began to take shape however dividing was done using a home made dividing plate that locked inside the back end of the spindle, the detent being attached to the gear spindles. This did seem to have a smidgeon of movement so that milled flat area was handy again but with this little attachment which locked things solid (a posed pic, as the other two, its bolted down when in use)
(https://lh6.googleusercontent.com/-h-RIUUb-OJ8/T9zr5sWjxrI/AAAAAAAAGaY/rpxvF9eRtNc/s640/DSCF0492.JPG)
Hope that is useful to you - I have posted these pics somewhere before - HMEM I guess - so apologies for repeating it but thought it might be worth while.
Well the snow has gone - looking at some parts of the country that makes us lucky - but that bitter wind is still blowing from the East - time to make those conrods ;)
Regards for now - Ramon
Edit Don - sorry, I didn't answer your question. If its basic dividing you want then 24 divs will probably suffice for most needs
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Very informative as always Ramon...those heads look fantastic too!!!
Bill
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NICE Ramon! Thanks for posting that again here!
24 or 48 wold be my answer too..
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Hi Guys, it's been a productive if somewhat interuptive couple of days. I finally bit the bullet and bought a shot blasting cabinet which arrived yesterday - the day after ordering it which is pretty good for 'free delivery' :) and, talking of which, I had ordered some 6082 ali for the prop drivers and prop nuts late on Friday off Ebay and much to my surprise it arrived, post free as well, on Monday morning just as I started the con rods :D Good service all round eh?.
The conrods are made from a tough aluminium called Alumec 89. It machines beautifully with an almost chromium like sheen and whilst it's easy enough to bandsaw it it's a real devil to hacksaw as it soon work hardens to that process. I first used it many years ago when working for a small jobbing workshop where we used to make moulds for a local blow moulding company and have had some scraps squirreled away for years ;)
Prior to the first Etas made, all con-rods had been milled. Turning them had previously been fought shy of because of holding them to form the second ball end. The drawings were laid out with milled rods but the fact that this was not correct to prototype began to bug and the idea of turning a tapered split bush to fit inside a collet was conceived. Much to my surprise that proved to be an efficient manner of holding them and the rods for the Super Tigres and this latest batch were made with relative ease. The making of these were covered on the Tigre build but I'll run through it again as it may be of use. Apologies in advance if considered repeating myself :-\
First off was to cut a slice of a small block then cut that into strips about 50mm long. These were quickly milled to square section .5mm over finished size then held in the SC4jaw turned to 11.1 diameter for about 30mm then reversed in a collet to give five round blanks
(https://lh4.googleusercontent.com/-ksgPevBh7bI/UVIlKxp6oqI/AAAAAAAAHVM/tjuVecSdvg4/s640/DSCF2292.JPG)
These blanks were then drilled and reamed on the mill, stops being set to maintain consistency
(https://lh4.googleusercontent.com/-qGlggXEclQA/UVIlR2ySi6I/AAAAAAAAHVk/7UBkl8_tR9g/s640/DSCF2300.JPG)
(https://lh3.googleusercontent.com/-419WCMtOFGc/UVIlUIHI_-I/AAAAAAAAHVs/5Vk1AjiYGuY/s640/DSCF2305.JPG)
Held in a 7/16" collet the first (bottom) end was formed using the original tooling made from a small piece of GFS
(https://lh4.googleusercontent.com/-ZhOSbrIn1XI/UVIlYuDLC2I/AAAAAAAAHV8/iJ6qe20koYY/s640/DSCF2313.JPG)
Then it was extended out of the collet to turn the shank, supporting it with the brass bush which has a 30 degree taper for the centre to impinge upon and a 45degree taper to support the rod. The shank is turned parallel to it's major diameter first, then taper turned using the topslide to flair into the big end. The excessive overhang of the tool is to allow clearance of the topslide against the tailstock - one of the very few annoying limitations I feel about the Myford.
(https://lh6.googleusercontent.com/-X6Iv2H1949M/UVIlbebm3KI/AAAAAAAAHWE/Jbqm5S6nXy8/s640/DSCF2327.JPG)
First stage looked like this along with the split bush turned at the same setting as the rods. The small end diameter is worked out
according to the length of the busht, drilled thru at that size then carefully bored until the taper cut finishes as it breaks the small end.
(https://lh3.googleusercontent.com/-mtXjV_3vrUI/UVIlkuYqzjI/AAAAAAAAHWk/76_u4r1Jidw/s640/DSCF2347.JPG)
Holding this in a collet provides more than adequate gripping power to form the second ball end. Incidentally the tool is set symmetrical about the hole by eye, inking up and moving the topslide until both sides of the hole appear even
(https://lh4.googleusercontent.com/-amJhcysVX8U/UVIlgD25KFI/AAAAAAAAHWU/chmPFv_Ge0Q/s640/DSCF2333.JPG)
The finished little end....
(https://lh4.googleusercontent.com/-fiAztVL5-EM/UVIliJ7lOvI/AAAAAAAAHWc/3tEntP5rEsA/s640/DSCF2340.JPG)
... and the finished rods
(https://lh6.googleusercontent.com/-bKj5Bj3Iwb0/UVIlm8vIlkI/AAAAAAAAHWs/7FimVcEZUoU/s640/DSCF2356.JPG)
Well there you are - a few more pics which I trust might prove useful to someone - there appears to be a lack of small engines such as these being mentioned on here - is anyone else making anything similar ?
I was hoping to have the prop drivers finished today too which would bring the ali parts to and end but time was not on side today so that will have to wait until tomorrow.
Regards for now Ramon
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Wow. Those are nice looking.
You make it all look easy...but I know it's not.
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Ramon...you could be making a garbage disposal and I'd watch!...... :praise2:
You just keep it coming and I'll pay attention!
Nice rods!
Dave
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Ramon, many thanks for your reply and I had drilled my ER32 collet chuck with 24 holes. I was wanting different for the chuck 50 and 48 seem adequate.
I did enjoy the way you did the Conrods. It's always at treat to learn something new watching your progress. As always great work. :praise2:
Don
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Always a pleasure Ramon.
Thanks for the update.
Dave
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Never seen it done that way. Looks easy with the form tools.
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Ramon, just curious as to what parts you are planning on shot blasting. I use it more for cosmetic reasons (machining marks, scratches, etc.) but your finishes on every part are so perfect it seems a shame to cover them up or modify them via blasting.
Bill
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Hi Guy's - good to hear you are finding this stuff useful or of interest.
You make it all look easy...but I know it's not.
Zee, none of this is difficult providing you think it through first and take the time to do things carefully. From what we've seen of your work so far it's obvious you do that anyway - you'd have no problem with any of this I'm sure ;)
Ramon, just curious as to what parts you are planning on shot blasting. I use it more for cosmetic reasons (machining marks, scratches, etc.) but your finishes on every part are so perfect it seems a shame to cover them up or modify them via blasting.
Bill
Bill, I think you may have missed post #61 where this is referred to.
I shall be using it predominantly for glass bead blasting rather than shot blasting. Most of these original engines had either sand or die cast cases. Bead blasting evens every thing out (though as I'm sure you are aware it won't eliminate tool marks - does grit do so? ) and helps give that illusion of a die casting. I haven't tried grit as yet - up to now I have used a friends cabinet which is set up for glass bead - but I would imagine that using coarser grit would give a reasonable impression of sand cast. With my own cabinet I will be able to change should the need arise though I would think that every trace of grit would have to be got rid of before going back to bead.
Finished the prop drivers this morning and managing to get some garden time in too. I'm out tonight but will try to add a bit later
In the meantime theres a lot of swarf to clear up before getting into the steel parts ;)
Regards - Ramon
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Thanks Ramon....actually I mean to say bead blasting...and you are right, it won't remove all tool marks but does give a nice matte finish which helps simulate the casting look. Then again, your machining is so nice there aren't many tool marks to remove in the first place :)
Bill
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Nice Rods Ramon. Do you not have one of the extended tool holders as they allow you to get in close without the post hitting the centre but still offer plenty of support for the tool.
(http://www.model-engineer.co.uk/sites/7/images/member_albums/44290/355515.jpg)
J
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Hi Guys, An update before the Easter break.
Jason, No I don't, though theres plenty of the normal ones to hand. I must confess up till now I've thought them a bit gimmickey but maybe I'll take a better look at the Midlands show in Oct. Thanks.
With all the ali parts now finished I'm taking a short break before tackling those crankshafts - probably next week sometime.
As said the prop drivers were the last to do and whilst on the surface these these seemingly innocuous little parts look like basic little turnings they do need to be machined with care if the propeller is to run in a true plane to the crankshaft. There are several means of attaching these to the crankshaft from a push fit onto serations, holes with a drive flat in them and varying means of tapers. I much prefer the separate, tapered split collet and matching driver, where the force of the prop nut tightens the collet to the shaft and one which provides a degree of self release. The 'challenge', if there is one, is to get the taper in the rear of the driver true to that front face which has to be knurled to provide a grip on the prop as well as, importantly, a matching taper on the collet.
In order to maintain this matching taper on the Racer build the front face was knurled then the taper was turned from the front face through the bore at the same setting but there was no way of really knowing when the taper was to size nor really able to see the surface finish (which needs to be good). Not exactly scientific nor ideal - there had to be a better way ::)
The following method was adopted on the first Eta build and proved successful. Used again on the Tigres and now these latest engines it has proved to be quite straighforward and gives an accurate part. Some pics then - hope you don't think this is overdoing it for such a basic part but as said it is one which can cause some head scratching.
Began with roughing the OD and front face and drilling a 6mm hole then parting off the blank
(https://lh6.googleusercontent.com/-qnI2H_e9f2Q/UVN0EWmVGFI/AAAAAAAAHXA/rcz2qR-Tea0/s640/DSCF2357.JPG)
Held by the faced end in soft jaws the rear face was faced , the bore opened up to 8mm by first taking a lick out by boring to true the hole and the taper turned - all ops using the same boring tool (this one's ground up from a discarded slot drill)
(https://lh6.googleusercontent.com/-A6DFY1_xga4/UVN0IuXsNQI/AAAAAAAAHXQ/BCokJ-4wSrw/s640/DSCF2366.JPG)
(https://lh6.googleusercontent.com/-0ek740JBJos/UVN0K1avMnI/AAAAAAAAHXY/ZVSuvFygVGM/s640/DSCF2370.JPG)
Popped back into the soft jaws the recess to define the knurled area was cut - not critical, the soft jaws providing more than sufficient concentricity ....
(https://lh3.googleusercontent.com/-4tB5OMZ2Fdo/UVN0NHdbe-I/AAAAAAAAHXg/INtLRQzd7_U/s640/DSCF2374.JPG)
....ready for knurling
(https://lh5.googleusercontent.com/-brcTLjJROXI/UVN0Qvu3yLI/AAAAAAAAHXo/wj047E1TgfU/s640/DSCF2378.JPG)
First off is to turn a mandrel. To maintain a matching taper means not moving the topslide so this is cut with the lathe in reverse
and using a boring tool - it's tapped 4 BA. This was already turned for a previous build but a skim is taken to true it up.
(https://lh6.googleusercontent.com/-rp2lL1wZHC0/UVN0Snc0hWI/AAAAAAAAHXw/rDKrmrllw3c/s640/DSCF2382.JPG)
The prop driver is held to the mandrel using a thick 'washer' which is stepped to just fit inside the bore. The knurl is not captive on the holder - it just slides onto a dowel and rotates freely and is prevented from moving by the washer. The lathe is run slowly - around 150 rpm and the knurl pushed into the 'driver using moderate pressure. It does need lots of coolant, I don't have a system set up so use a squeezy bottle to flood it. It's better to back off and clean the knurl - it will soon 'pick up' again if brought up slowly - as the chips formed can soon spoil the effect if allowed to be crushed into the grooves
EDIT Ooops :o I've missed a small but essential op out - the knurled area is skimmed before knurling to bring this true to the taper
(https://lh6.googleusercontent.com/-p6phm3edj_Q/UVN0U4v3hcI/AAAAAAAAHX4/gWWjYqM8JcQ/s640/DSCF2387.JPG)
(https://lh6.googleusercontent.com/-ZPl_TxDS1g4/UVYJprfNZMI/AAAAAAAAHZo/7nCM2Fw4oJE/s640/DSCF2392.JPG)
Ready for finishing off ....
(https://lh4.googleusercontent.com/-KX7QT0a8NFc/UVN0Z_Ntz8I/AAAAAAAAHYI/PungUI4NHBs/s640/DSCF2398.JPG)
.... but first the collets need making before that topslide setting is broken. Made from brass - could be free cutting steel but ali is a definite no no as in use it could 'pick up' on the driver and prove a devil to remove. The collet is reamed to suit the shaft (6.35mm) and the taper turned as for the mandrel by running in reverse and using a boring tool
(https://lh6.googleusercontent.com/-9kjHe4VPgBo/UVN0cHSubJI/AAAAAAAAHYQ/fsMhzgQuTOY/s640/DSCF2402.JPG)
A driver is positioned on the collet and a parting tool set to the back face
(https://lh3.googleusercontent.com/-ARBxe0JN7UU/UVN0ecVi_xI/AAAAAAAAHYY/6cpayVCU7Bg/s800/DSCF2407.JPG)
With the blank removed the tool is advanced .25mm to define the rearmost face then withdrawn .5mm and plunged to create a step at the base of the collet. (Sometimes when these collets are split they close tight onto the shaft. This step allows something flat to act as a lever to prise it away from the step on the crank shaft enough to be able to grip it. (Believe me, they're a real pain to remove if theres no step ::))
(https://lh5.googleusercontent.com/-ZgP5rVLbdfU/UVN0gf_kECI/AAAAAAAAHYg/RPzko2jcE3M/s640/DSCF2411.JPG)
With the collets all finished the mandrel is set back up, given another skim then the topslide can finally be moved to finish turn the OD true to the taper
(https://lh5.googleusercontent.com/-rLunIiQoyKs/UVVh6JTjXjI/AAAAAAAAHYw/BeHp8ObE6oE/s640/DSCF2416.JPG)
And there they are ready to fit :)
(https://lh4.googleusercontent.com/-waAm9TL3ts8/UVVh8aIti0I/AAAAAAAAHY4/aq7R6r9dqgo/s640/DSCF2421.JPG)
Well I hope that isn't seen as overkill but theres nothing worse that seeing a prop describe a circle fluctuating back and forth as it does so - as you can no doubt imagine the driver does not have to be out much for the blade to be well out at the tip - so I hope that's of interest to someone.
Tomorrow looks like another cold wet one but what the hell we're going sailing :D
As 'Redneck' Eric would have it - y'all have a good Easter break now :ThumbsUp:
Regards Ramon
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You too Ramon!
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Thanks Ramon, that was a nice write up, and I appreciate the detailed explanation.
Lee
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Very interesting Ramon. I always wondered how those lines are made on the prop driver. Now I know.
Thanks
Vince
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Just thought you'd like to know that as of this morning decided to take a different approach to this project - I'm not sure this will work but you never know it might just ;D
(https://lh3.googleusercontent.com/-kFAVduphNng/UVljXBxpsvI/AAAAAAAAHaE/x6RGSzBS0II/s640/in%2520line%2520triple.jpg)
Rabbits, rabbits rabbits - it's not yet twelve o' clock ;)
regards - Ramon :)
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An inline tripple Ramon? Or did you have something else in mind?
Bill
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Is that A Prototype Radical In Line engine? if so it will be the 1st of its kind.
I think you have been eating too much strong chocolate over the weekend.
J
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I think Ramon is trying to make them multiply like rabbits. :LittleDevil:
Vince
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It's surprising the difference a week can make - I've decided to carry on as before ;)
Got back onto it today and began the crankshafts. Made from En24t (4340) a decision was made to do one conventionally and make it from one piece - this will be used for the engine that might :o actually see an airframe the others being composites as has been made in all engines todate.
Began by facing the blanks and centreing one end before roughing the front ends down to a consistent 14mm diameter. This would be thick enough to withstand milling around the crank pin without leaving too much to come off and, as a vee block was to be used for centre drilling the crankpin location would give the consistency of offset required through all four.....
One of the rare times the lathe sees carbide tooling - it does help deal with roughing such tough material but the power drive isn't really up to the capability of the tool - I lost a couple of tips when the spindle slowed rapidly to a stop.
The shorter, composite, shafts were also drilled and reamed 7mm at this stage as well.
(https://lh3.googleusercontent.com/-e8bDCBR-jwM/UV8yFvO5vaI/AAAAAAAAHaU/BbDyYzteS4A/s640/DSCF2433.JPG)
Using the crank pin turning fixture to centre drill the c'pin location
(https://lh3.googleusercontent.com/-wf2ffWNMlOM/UV8yHuMhARI/AAAAAAAAHac/2YGwUfu8sSs/s640/DSCF2438.JPG)
Held in a vee grooved plate to mill away the waste around the crankpin. Major area first then rotated 90 degrees each side to mill the sides
(https://lh5.googleusercontent.com/-fqSFaz8xGrc/UV8yJuEDbCI/AAAAAAAAHak/14zRbmrZNdY/s640/DSCF2443.JPG)
Last roughing op was to bring the c'pin to circular section using the fixture above
(https://lh3.googleusercontent.com/-VBSZRHcPYJo/UV8yLg2VOfI/AAAAAAAAHas/9l9PABpliFw/s640/DSCF2449.JPG)
Current state of play tonight ready for making and fitting the secondary shafts before the finish turning between centres
(https://lh5.googleusercontent.com/-WxEFPeX5ykE/UV8yNtRH_6I/AAAAAAAAHa0/lO8UF0DFwzU/s640/DSCF2453.JPG)
The reason for the composite shafts is none other than conserving the limited supply of En24t. The secondary shafts will be turned from High Tensile cap head bolts and made a good press/loctite fit. So far this method of manufacture has proved more than capable to withstand the forces involved though of course they are only ever run on the bench - hence the decision to make the potential flying version from one piece - just in case ;)
Sailing tomorrow :) - looks like the weather may actually be reasonable so it'll be a day or two before the next stage.
Regards for now - Ramon
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Ramon you just keep coming up with new stuff for me to build. Love you fixture it's so useful for both lathe and mill. Still following along here with great interest.
Don
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Ah! "Sorry about that" Don :D - I must admit it is a versatile and very useful but easily made fixture, it certainly gets plenty of use on these small engines.
A small anecdote - "Sorry about that" is in quotation as we had a draughtsman/designer who was renowned for mistakes which would swiftly be dismissed with a pencil stroke or two and the utterance of those three words. The guys in the toolroom chipped in and we had a proper rubber stamp made with the legend 'A Genuine RJJ Sorry About That' with which all relevant drawings were gleefully stamped ;D
Following on from the last post the 'secondary' inner shafts were turned from the shanks of 8mm high tensile cap head bolts and with a smear of high strength Loctite pressed in using the small home made flypress.
Set back in the lathe in soft jaws the shafts were roughed down to plus .5mm on diameter and faces on the front ends.
(https://lh5.googleusercontent.com/-5DTA1i6lOQE/UWSE6LYQXDI/AAAAAAAAHbY/vq-lhq4ZQU8/s640/DSCF2459.JPG)
This may be of interest to some one ..... I don't use the leadscrew for such turning - just the saddle handwheel but it was always felt that the standard Myford version is a bit small as far as leverage is concerned so a while back I made a new saddle handwheel which has improved matters considerably on this kind of op as well as general turning - certainly wouldn't go back to the old one now. ;)
(https://lh6.googleusercontent.com/-LuIicqUVn7I/UWSE8vzDTfI/AAAAAAAAHbg/rmxj-XiboQs/s640/DSCF2460.JPG)
After the secondary roughing they were ready for finishing between centres
(https://lh4.googleusercontent.com/-R_xv8a30fgQ/UWSE_fQ25EI/AAAAAAAAHbo/fr3AVe0M2mI/s640/DSCF2467.JPG)
This little driver plate has seen considerable use now. The centre is removeable as it is trued each time it's used to ensure concentricity - it's just about ready for that next time.
(https://lh6.googleusercontent.com/-uhsw3X7evvI/UWSFBllrjEI/AAAAAAAAHbw/M4ZWSo3suyM/s640/DSCF2468.JPG)
The shaft can now be finish turned using the crankpin as a driver - the red line denotes the limit of thread. These were turned to 0.03-04mm up on diameter and then polished down to size with fine emery and oil
(https://lh4.googleusercontent.com/-gsTQ0teuuPQ/UWSFEK0njiI/AAAAAAAAHb4/HqPbC4GBVYk/s640/DSCF2473.JPG)
The shafts could be screw cut at the same set up but were done as a secondary op to the finishing - no gear box :)
(https://lh4.googleusercontent.com/-zUnyWZYktr8/UWSFGQRGKLI/AAAAAAAAHcA/UEi1-Vsqmgw/s640/DSCF2478.JPG)
With the front ends finished that fixture was pressed into service on the faceplate for turning the crankpins to finished size - the reduced portion is the drive for the rotor disc. Don't take any stock by the tool - I confess that when it comes to grinding lathe tools I'm the laziest around - it's very much if it will cut efficiently it'll do. I guess after all it's only the very point that does the work ;)
(https://lh6.googleusercontent.com/-KYCEGyXcUbk/UWSFR_LqMpI/AAAAAAAAHco/WuqGFoe07Dk/s640/DSCF2502.JPG)
The shafts after finish turning ready for that last op - shaping the web and one which is always a bit fraught after all the work gone before.
(https://lh3.googleusercontent.com/-KFVzAyBjJBw/UWSFUbm1fHI/AAAAAAAAHcw/20nfP8wK-xo/s640/DSCF2512.JPG)
I usually use a vise and a vee grooved parallel to hold the shaft but this time decided to use a block made at work for grinding work - like a big finger plate only 50mm thick. I don't know why I haven't thought to use it before as it was perfect for the task ::) Unfortunately the pics taken are really blurred but I'll take some more tomorrow.
All went well though so that's another part done .....
(https://lh4.googleusercontent.com/-VV0gS9WQVXc/UWSFWjI5IjI/AAAAAAAAHc4/QMPKFK9v2Fk/s640/DSCF2533.JPG)
All the parts made so far are individually bagged in small polybags to offer some form of protection. The box they're in grows fuller but there's still a way to go yet. The plan is to keep on with all the steel parts now so it's the liners next and some of the smaller ancillary bits.
That's it for now -
Regards - Ramon
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That's very instructive, Ramon. Are you roughing out with carbide and finishing with HSS? The end result looks superb, well,from this far away at least.
Hugh.
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Ramon, I have a question in regards to your soft jaws. Is the chuck a Myford original or one with soft jaws that came with it? I have been looking for soft jaws for my existing chuck, but can not seem to find them. A chuck with soft jaws cost quiet a bit.
Your cranks came out great. Do you always use bolt material for the threaded portion of the shaft?
Don
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I like that fixturing Ramon, clever idea using the crank pin as the driving ""dog." The crankshafts certainly did come out well but I didn't expect otherwise :)
Bill
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Hi Bill, Don, Hugh, et al, good to hear from you as usual.
Don, That three jaw - a Pratt-Burnard precision ground scroll would you believe, goes way back to my first ML7 (possibly even the ML10 before that - does that have the same chuck mounting as the 7 ? Now that is a long time ago :old:) It's done sterling service but has seen better days now. It was very pricey in it's day but when I tried to replace it a year or three back the cost was simply astronomical :o and totally unjustifiable.
The soft jaws were bought from an agent who used to regrind all our cutters - they've been in use a long time and I am very frugal with machining them - the tapped holes are for holding slices of hexagon bar which further extend their use - I do have a spare set but was thinking the other day that these ones could be resurrected at some stage by silver soldering pads to the front as they are only mild steel after all - any one else done that?
Re the use of high tensile bolts Don, so far all the engines I've made have had the shafts made this way. Initially done to conserve a small, and only, piece of En24t it proved a viable way to limit the amount of this material both from an availablity and excess machining point of view. With that front end reducing from 32.0 diameter to 6.35 quite a bit of material and energy is saved. Bear in mind these engines will only ever get bench run though they are given their head when the situation allows. So far nothings gone awry - yet ;)
Hugh, I'm not keen on using carbide at home. Well versed to using it at work I feel the power of the Super 7 isn't really up to the demands of using the carbide efficiently so virtually all turning is done using HSS. I was given this tool by a good friend quite recently and decided to see if it would speed up matters on this En24t which it has - a big improvement over HSS but I still don't see a need to use it generally other than tough material or the odd hard spot in a casting.
Re that block referred to last night - heres some pics of the set up to mill those webs...
(https://lh4.googleusercontent.com/--ZcPrH1avpk/UWW-7yZT7YI/AAAAAAAAHdI/6wJgC-Z8W9w/s640/DSCF2535.JPG)
The block was made at work from some extremely tough cast iron - a redundant twenty ton press bedplate.Wheeled into the machine shop by the press shop foreman one morning with a 'Is this any good to you otherwise it's going in the bin remark' it was swiftly reduced to sizable chunks and stored for that rainy day ;). Have no idea of the grade but very tough. I made the Waller cylinder from a piece of it and also a dividing device for the mill before redundancy took over - I guess like so much else it all ended in the scrap bin
It has three vee grooves ground in and plenty of tapped holes for clamping screws.
(https://lh4.googleusercontent.com/-bPtfWlD8zUc/UWW--I-aJTI/AAAAAAAAHdQ/OLtAHEyYg1k/s640/DSCF2536.JPG)
It was much easier to align the centrel line of the pin to that of the shaft than when held in the vise....
(https://lh6.googleusercontent.com/-juVjfysjxAs/UWW_AvjK0pI/AAAAAAAAHdY/qCZTYW84aaI/s640/DSCF2521.JPG)
....and then mill either side to stops.
(https://lh6.googleusercontent.com/-nPztelnNukQ/UWW_GrOGnzI/AAAAAAAAHdo/xmTw8pnRUJw/s640/DSCF2537.JPG)
I don't think I've used it since leaving work - that could now change ;D
Made a start on the liners today. Once again these are made from freecutting En1a which is a good combination with a cast iron piston. Bored the blanks to size first using the expanding mandrel made for the previous ones as a plug gauge then roughed the outer surfaces in the chuck before finishing the outer surfaces to the bore on the same mandrel.
Finished ready for milling the transfer and exhaust ports
(https://lh4.googleusercontent.com/-3myV0FGUh6U/UWW_UgzQtlI/AAAAAAAAHeY/ctHKkikY-sk/s640/DSCF2571.JPG)
Where's the fourth one? Well that is a spare left over from the prevous engines and just needs the ports finishing by filing - more on those ops later.
The weather at last has turned so that can mean only one thing - distraction - the garden beckons ::)
Regards for now - Ramon
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Ramon, it's always a pleasure to log onto your posts . There's always something to learn and admire.
following with great interest
peter
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Ramon,
I do have a spare set but was thinking the other day that these ones could be resurrected at some stage by silver soldering pads to the front as they are only mild steel after all - any one else done that?
Since buying my far eastern lathe about 5 years ago, I have stuck with far eastern chucks, both 3 and 4 jaw self centering, as 50% of my turning work is done using soft jaws, most of the other work is done in a collet chuck. They are very cheap to buy for these far eastern chucks, normally around 25 UK pounds per set.
So if I am doing any normal turning with the scroll chucks using the normally supplied hard jaws, parting, facing etc, they are plenty good enough anyway.
So for the person who doesn't have a lot of cash to spare to buy very good quality chucks, far eastern chucks are a good compromise if you do a lot of soft jaw work, as there is no difference after they are bored to size from a very expensive one.
I think I have bought almost all of mine from RDG, here in the UK.
Very good write ups and descriptions BTW. :praise2: :NotWorthy: :praise2:
John
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Hi Bill, Don, Hugh, et al, good to hear from you as usual.
Don, That three jaw - a Pratt-Burnard precision ground scroll would you believe, goes way back to my first ML7 (possibly even the ML10 before that - does that have the same chuck mounting as the 7 ? Now that is a long time ago :old:) It's done sterling service but has seen better days now. It was very pricey in it's day but when I tried to replace it a year or three back the cost was simply astronomical :o and totally unjustifiable.
The soft jaws were bought from an agent who used to regrind all our cutters - they've been in use a long time and I am very frugal with machining them - the tapped holes are for holding slices of hexagon bar which further extend their use - I do have a spare set but was thinking the other day that these ones could be resurrected at some stage by silver soldering pads to the front as they are only mild steel after all - any one else done that?
Re the use of high tensile bolts Don, so far all the engines I've made have had the shafts made this way. Initially done to conserve a small, and only, piece of En24t it proved a viable way to limit the amount of this material both from an availablity and excess machining point of view. With that front end reducing from 32.0 diameter to 6.35 quite a bit of material and energy is saved. Bear in mind these engines will only ever get bench run though they are given their head when the situation allows. So far nothings gone awry - yet ;)
Hugh, I'm not keen on using carbide at home. Well versed to using it at work I feel the power of the Super 7 isn't really up to the demands of using the carbide efficiently so virtually all turning is done using HSS. I was given this tool by a good friend quite recently and decided to see if it would speed up matters on this En24t which it has - a big improvement over HSS but I still don't see a need to use it generally other than tough material or the odd hard spot in a casting.
Re that block referred to last night - heres some pics of the set up to mill those webs...
(https://lh4.googleusercontent.com/--ZcPrH1avpk/UWW-7yZT7YI/AAAAAAAAHdI/6wJgC-Z8W9w/s640/DSCF2535.JPG)
The block was made at work from some extremely tough cast iron - a redundant twenty ton press bedplate.Wheeled into the machine shop by the press shop foreman one morning with a 'Is this any good to you otherwise it's going in the bin remark' it was swiftly reduced to sizable chunks and stored for that rainy day ;). Have no idea of the grade but very tough. I made the Waller cylinder from a piece of it and also a dividing device for the mill before redundancy took over - I guess like so much else it all ended in the scrap bin
It has three vee grooves ground in and plenty of tapped holes for clamping screws.
(https://lh4.googleusercontent.com/-bPtfWlD8zUc/UWW--I-aJTI/AAAAAAAAHdQ/OLtAHEyYg1k/s640/DSCF2536.JPG)
It was much easier to align the centrel line of the pin to that of the shaft than when held in the vise....
(https://lh6.googleusercontent.com/-juVjfysjxAs/UWW_AvjK0pI/AAAAAAAAHdY/qCZTYW84aaI/s640/DSCF2521.JPG)
....and then mill either side to stops.
(https://lh6.googleusercontent.com/-nPztelnNukQ/UWW_GrOGnzI/AAAAAAAAHdo/xmTw8pnRUJw/s640/DSCF2537.JPG)
I don't think I've used it since leaving work - that could now change ;D
Made a start on the liners today. Once again these are made from freecutting En1a which is a good combination with a cast iron piston. Bored the blanks to size first using the expanding mandrel made for the previous ones as a plug gauge then roughed the outer surfaces in the chuck before finishing the outer surfaces to the bore on the same mandrel.
Finished ready for milling the transfer and exhaust ports
(https://lh4.googleusercontent.com/-3myV0FGUh6U/UWW_UgzQtlI/AAAAAAAAHeY/ctHKkikY-sk/s640/DSCF2571.JPG)
Where's the fourth one? Well that is a spare left over from the prevous engines and just needs the ports finishing by filing - more on those ops later.
The weather at last has turned so that can mean only one thing - distraction - the garden beckons ::)
Regards for now - Ramon
Nice Fixture Ramon!.....I like it!
Thats about 100 x 50 x 25 or so?
Dave
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Hi John, Thanks for your input.
Yes I have a far eastern 5" 3jaw still awaiting the back plate to be fitted though I do not have any soft jaws for it as yet . As you say, cheap or expensive, the beauty of soft jaws render either attribute more or less equal :D
The PB chuck has the internal Myford fitting and that was what I was more interested in in replacing. Having decided a new one was out of the question I was fortunate enough to find a little used replacement at the last but one Myford Open Day. This is a Toolmex version with a heavy reversed backplate and internal thread. Using it yesterday to bore those liners it literally seized solid, the jaws stuck half way. I stripped it down to find it absolutely full of swarf and thick grease. Examination showed that the back plate inner face doesn't meet the chuck inner face so allowing swarf to get in. An o ring popped in between will hopefully put an end to that.
Dave (Steamer), a little bigger - it's 125 x 75 x 50
Regards - Ramon
Peter - My apologies, I didn't mean to ignore you. Thanks for your kind comments - it's good to see you have an interest but yours ,for me, is much more inspiring :ThumbsUp:
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Hi Guys had a repreive today - it rained like hell ::) only one place to be then ;D
Just a few pics of cutting the porting in these liners which may be of interest to someone. Not a difficult operation but one that has to be done with a degree of accuracy if the timing is to remain as designed. The original liners were quite 'high tec' in their day - for model aircraft engines that is - in that they were investment cast steel and had the transfer ports cast in. Close examination of the Mk1 & 2 originals showed the tops of the transfer ports to be flat and square to the bore whereas most other engines of the day having angled ports being drilled or milled giving an elipse form inside the liner. I filed the Mk 1 & 2 ports to a gauge but it occurred doing these that providing the holes were correctly located filing could be done until the inked up port just showed an indication of ink. The ports were made a bit larger as per the liner in the Elite that I was loaned. You will notice some slight difference in them - that is by choice, just to see if theres any performance difference.
First off was to mill the passages...
(https://lh3.googleusercontent.com/-yUguHcsToVM/UWhkWqJopNI/AAAAAAAAHeo/C8u4CmsqGxM/s640/DSCF2575.JPG)
...then set the milling attachment at 35degrees and plunge cut the ports with a 3mm FC3 cutter. The position of this was established by CAD and datumed off the lower surface of the exhaust flange which is the datum face for the timing for both ports. The liner was moved radially to widen the cut to match the passages by engaging backgear and applying radial motion by turning the main drive pulley by hand - there's a surprising amount of control doing it like that :)
(https://lh5.googleusercontent.com/-c_gLCZY9OGA/UWhkZb3_BpI/AAAAAAAAHew/q2Wke838zTM/s640/DSCF2579.JPG)
The cut outs were done at the same time as these would be used to align the liner to the rotary table for the next op....
(https://lh4.googleusercontent.com/-W1hRvDjypHw/UWhkb03YssI/AAAAAAAAHe4/fmvsuGi8RYs/s640/DSCF2589.JPG)
....which was to cut the exhaust ports using the same cutter as was made for the Mks1 & 2
(https://lh3.googleusercontent.com/-TVAAVgLT22M/UWhkedPR1QI/AAAAAAAAHfA/p5O1Dt8-0VE/s640/DSCF2591.JPG)
All finished ready for lapping. The one with the fins on is for the Elite Mk2 which had shrunk on fins and a separate head. I popped the liner in the freezer whilst I had my dinner and then later heated the fins with a hot air gun. Despite having a rod through the bolt hole as a guide to align the bolt hole with the pillar between the exhausts the speed at which it contracted did not give enough time to get perfect alignment ::) It ain't coming off now though
(https://lh4.googleusercontent.com/-ivRFPFrNUVM/UWhkhIW3ztI/AAAAAAAAHfI/5Tbu9kbE5LM/s640/DSCF2600.JPG)
It will be a while before the lapping gets done - I'll leave the cast iron till last. Next will be some of the less exciting ancillary bits - cylinder bolts and rotor pins etc - in the meantime the box of goodies grows :)
(https://lh5.googleusercontent.com/-G47WURiBuwY/UWhkjawbgOI/AAAAAAAAHfQ/k-BDZGgYo-g/s640/DSCF2606.JPG)
Time for a day off, weather looks favourable tomorrow - it's my first race :o
Have a good weekend now :)
Regards to all - Ramon
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Hope the wind blows for you, assuming its a sailing race.
J
PS Good to see your article in MEB.
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Hope the wind blows for you, assuming its a sailing race.
J
PS Good to see your article in MEB.
Ditto! Nice article and hope you do have fair winds!
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Hi Ramon,
What a Brilliant article, the finish you have on the engine body is better than die castings.
The machining tips, tooling, and set ups are excellent. I used the holding fixture for taper ball handle making way back when building the Quorn T&C Grinder, and I agree it was very useful , pleased you passed that one on. I have made made quite a few special milling cutters using the same materials and hardening techniques as yours, however it never occurred to me to make the cutter heads separately. It saves on materials, can be easier to make, and the shank can be used for various heads.
I started reading this article today and couldn't put it down like a good thriller.
Well Done Cheers David
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Hi Guy's - where on earth has that week gone ? Time certainly flies when you're enjoying yourself that's for sure.
Firstly thanks for your kind words David - it's always nice to hear that someone benefits.
Despite some garden distraction what time managed in the workshop has been well spent though. All the cylinder head bolts are turned and slotted, the stainless pan head screwshave been reshaped to round heads and the rotor disc wear plates and rotor pivot pins made.
The wear discs were apparently an aftermarket part no doubt to reclaim a worn backplate face. The original Mk1 I had loan of did not have one fitted and the circular wear marks were quite prominent in the ali surface. The 5cc Mk 1 was left as per the original but the Mk 2 had a plate made which is also what has been done here on all four.
The original appeared to be a stamping but these have been made by parting off some En1a of the correct diameter about 1mm thick then holding it in soft jaws and facing it to 0.8mm. The blanks were then lapped to a fine finish on the wearside using a pot magnet as a holder. Lapped on a lapping block to begin with they were finished by polishing on 2500 grit Wet and Dry on a ground cast iron surface.
Still holding it in the soft jaws the inlet segment could be removed - I thought of Vince and his flywheel doing this - same op, just a lot smaller but no doubt same anxieties ::)
The edges were defined first - any error here alters the desired timing.
(https://lh6.googleusercontent.com/-Jtw1K60DVxQ/UW_TccCJjAI/AAAAAAAAHfw/9b28Vzvi9jo/s640/DSCF2608.JPG)
Then the segment removed
(https://lh6.googleusercontent.com/-gyskdNdFGtY/UW_Te8ZLfxI/AAAAAAAAHf4/Fvc5QvL4_B8/s640/DSCF2611.JPG)
They fit into the recess in the backplate and are held by the rotor pivot pin. No means are there other than clamping pressure of the pin to prevent them rotating - obviously if they did it would alter the timing but that isn't something that's occurred so far
(https://lh6.googleusercontent.com/-e3XDJJEQHGI/UW_ThWut6rI/AAAAAAAAHgA/G_2o3kh5-BI/s640/DSCF2617.JPG)
I can't remember who but someone was recently asking about rounding something in the lathe - these stainless screws were soon reshaped using a home made cutter - the profile was just milled into a piece of GFS and heat treated. Note the colour - because of the amount of screws to do and their toughness this was tempered to light straw.
Shape to begin with...
(https://lh4.googleusercontent.com/-S9bZIErsylY/UXGmM9pP7aI/AAAAAAAAHgQ/xbMGqcoLdZI/s640/DSCF2619.JPG)
....and finished.
(https://lh6.googleusercontent.com/-w2HrjxGJuSc/UXGmPSF3eMI/AAAAAAAAHgY/eG8g1RHTr7k/s640/DSCF2628.JPG)
The tool shows no sign of wear after shaping 48 screws - that includes 16 on the previous engines. Hope that's of use to someone.
The rotor pins were turned from silver steel and screw cut UNF 8-32 L/H. (Only suitable L/H tap available). I've screwcut some pretty varied materials over the years but nothing can be worse than silver steel. for some reason this material is always a pig to screwcut and this time would prove no different. That said only one had to be made twice and the rest though not brillliant were acceptable.
These were heat treated one at a time so as to give good 'positional' control when quenching. By plunging them into the oil squarely to the surface any potential distortion is kept to a mimimum - particularly at the narrow point where the thread runs out.
A piece of copper tube was tapped to hold the threaded end and the main body of the pin then heated to a bright red. Once up to that it was removed from the flame for a few seconds and allowed to cool to a dull red before quenching in oil. Doing this helps stabilise the temp through the part.
These couple of shots are posed after using the scrapper but give some idea of the colours involved. Because of having to handle the camera this first image has the part somewhat brighter than would be the normal colour taken to.
- this is actually much too hot.....
(https://lh5.googleusercontent.com/-I6zGqtsBBlI/UXGmUbFiHNI/AAAAAAAAHgo/V9HtB9I2DXI/s800/DSCF2634.JPG)
.....this is more the 'red' ready for quenching
(https://lh6.googleusercontent.com/-zxRUumdfiNY/UXGmWYp_AcI/AAAAAAAAHgw/T-iSBTH3oJc/s640/DSCF2637.JPG)
Once quenched the pins were polished back to bright steel and cleaned of all traces of oil before tempering in a tray of hot sand.
The sand should be very hot before putting the part in as this helps ensure consistency if multiple parts are being treated. It is not a good idea to put more than one part in at a time as once up to temp required it's surprising how quickly it will travel through it's desired colour and once past - well ::)
(https://lh6.googleusercontent.com/-W0JxZA-B42Y/UXGmRsaKEFI/AAAAAAAAHgg/r74C-2xuwbQ/s640/DSCF2631.JPG)
Finished ready to fit to have the rotors fitted. Though they look near black in the image they are in fact a nice blue going on brown to look at in shop light - well pleased with the outcome
(https://lh3.googleusercontent.com/-0v0Di7143Gc/UXGmYhD_dlI/AAAAAAAAHg4/zw_eSGsAxlc/s640/DSCF2640.JPG)
Think I should just say that the above re heat treat is based purely on practical work experience and not one of academic knowledge - this is not to teach granny - just my way of going about heat treat at home based on many hours of doing it correctly with the proper kit in a commercial environment.
Well that's as far as things are at the moment - the rotors are next so the workshop will be permeated with that nice aroma of machined tufnol and after that its on to the pistons and finally some fitting work :)
As always hope this of use to some one
Regards - Ramon
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Beautiful work Ramon,
Some interesting tips on heat treating; thanks so much.
When you screw cut the crankshaft threads how do you finish the inboard end? Is there a thread relief or do you pull the threading tool out at the proper time? If the latter do you have any tips on how to do this consistently for each cut?
Thanks for taking the time to post your wonderful work.
Dave
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Very interesting post Ramon.
I know next to nothing about heat treating and found this very helpful.
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Once quenched the pins were polished back to bright steel and cleaned of all traces of oil before tempering in a tray of hot sand.
The sand should be very hot before putting the part in as this helps ensure consistency if multiple parts are being treated. It is not a good idea to put more than one part in at a time as once up to temp required it's surprising how quickly it will travel through it's desired colour and once past - well ::)
(https://lh6.googleusercontent.com/-W0JxZA-B42Y/UXGmRsaKEFI/AAAAAAAAHgg/r74C-2xuwbQ/s640/DSCF2631.JPG)
Ramon many thanks for your detailed descriptions and photos. The pan of sand was heated before placing in the pin in did you have to heat the sand while the pin was in the sand? What was the heat source? It looks like the pan is setting on something is that a heater or a stand?
Dan
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Hi guys just home from a good days sailing :) Thanks as usual for your kind comments and input. Glad to see you are still hanging in here Zee :)
When you screw cut the crankshaft threads how do you finish the inboard end? Is there a thread relief or do you pull the threading tool out at the proper time? If the latter do you have any tips on how to do this consistently for each cut?
Dave
Hi Don, a good question. Because of wanting to maintain maximm strength in the shaft no there's no relief which means, as you say, pulling the tool out in time. Theres no 'scientific' way to do this by hand just by eye and quickness - setting the speed to match your personal reaction is about the only thing I could say that helps. Sometimes it catches you out when you're a little slow on the up take but worst is bringing it out too quick leaving more to take off the next time. A run out for the thread is much the better way to go if possible.
Ramon many thanks for your detailed descriptions and photos. The pan of sand was heated before placing in the pin in did you have to heat the sand while the pin was in the sand? What was the heat source? It looks like the pan is setting on something is that a heater or a stand?
Dan
Hi Dan, Yes the small tray - the ubiquitous tobacco tin - is standing on a butane camping gas stove on a low flame throughout the process. Reason for getting the sand hot first is to stabilise the temp of the sand. If you put a part in and then heat the sand it takes quite a time for the colours to begin to show and theres the temptation to be distracted - typically that's when the heat 'magically intensifies' and takes the part beyond the colour/temper desired ::) The sand is HOT - keep your fingers away - don't ask ::)
BTW the sand should be very dry - if it's damp when first setting this up then let it heat up for a good while turning the sand to totally get rid of any moisture.
The other thing worth a mention is if a part is quenched out after tempering and it's thought it should be given a bit more don't put it back into the sand expecting a further colour change as this won't happen - the part has to be recleaned back to bright steel - all traces of oil removed and the part re tempered. This will then show a colour again without affecting the temper of the part other than at the 'new' colour. (Of course this doesn't apply if it's been over tempered in the first place) Tempering twice is usually carried out on a commercial basis on GFS/Silver steel equivalent metals so this will not affect the part.
If a part is over tempered then it can be reheated and quenched and then re-tempered however the reheating for hardening tends to bring the carbon to the surface and this can leave a soft skin - not very thick agreed but something, if not aware of, thick enough to sometimes confuse when a file is rubbed over to check for hardness.
Hope this helps a bit more,
Regards - Ramon
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Still watching with much interest Ramon. Excellent pictures and a great build log in all respects.
Bill
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Hullo again everyone,
A few days ago I placed a new post on the forum to the effect that I was disillusioned and was departing MEM.
That was due to my reaction to what I considered an uncalled for and somewhat heated response toward me in another post. It was not one of dummy throwing or the fact that someone had disagreed but quite simply that if this is how this is to be at times I'm afraid there's no part for it in the quiet life I try to lead.
As the post life was extremely short most members will probably be unaware of the situation but the whole thing was quite upsetting. However what took me back, and I have to say completely by surprise, was the virtual immediate response both on the thread and via PM's by fellow members including two moderators asking me to reconsider.
It was after a discussion with Sue then, who reminded me of my own philosophy that sometimes events make it so easy to get negative due to one unpleasant thing rather than to remain positive about all the good things that I began to realise what I was going to miss. With that in mind I set out to try to have the posts removed but found that in this short space of time not only had they been removed but that I had also been banned for a week - cut off at the stocking tops as the saying goes - unable to respond even to defend myself.
It's said "a week is a long time in politics" and these last few days seemed very long indeed but did give me time to rethink the situation. Although the thought 'I don't need this in my life' was still very much in my mind that was tempered by realising just how much pleasure this forum and all the 'forum friends' I've met on here actually matter. I don't belong to any clubs - this (and HMEM) is my club.
Suffice to say with the support of the Admin team (and to whom a huge thank you is in order) the ban has been lifted and I'm very much back on song.
Some things are sent to try us - sometimes they are trivial in hindsight but at the time they don't feel like it - lets hope this is the last time this happens to anyone on here - if I was French I could only cry 'Vive La MEM'
Enough - What's done is done - time to move on. Let's talk about engines :)
I have been beavering away when the super weather and subsequent garden distraction would allow. I had a very pleasant morning over my friend Lee's the other day to bead blast the cases - No pics as yet as they need a dip in the ultra sonic cleaner before assembly but all parts are now made save for the wrist pins. Assembly is not far away then.
Here are a few pics to bring it up to date - well nearly .....
The rotors were made from Tufnol again but this time the rough diameter was turned to fit that clamping plate that gets so much use. It made the transfer from lathe to mill much easier for this part.
(https://lh4.googleusercontent.com/-xZcoatwYnBU/UYbDD_7KujI/AAAAAAAAHks/vg5krR9lz04/s640/DSCF2660.JPG)
(https://lh4.googleusercontent.com/-43uEM-AV9YQ/UYbDHD4x4sI/AAAAAAAAHk0/rS-nYVPExhw/s640/DSCF2665.JPG)
(https://lh4.googleusercontent.com/-GqZNqBqJKOY/UXooG2fK1VI/AAAAAAAAHhQ/KOS64cmXBY0/s640/DSCF2674.JPG)
The needle valve parts were next. The needles are made from 16swg piano wire and ground by rotating it on the side of the off hand grinder before running it in the lathe and supporting it at the tip by a piece of hardwood. The tip can then be trued and polished using a worn needle file conventional or diamond. This method produces quite concentric and efficient needles.
(https://lh4.googleusercontent.com/-9urM55Yb8U8/UXooJ0kSE0I/AAAAAAAAHhY/IXv_9S5rgNQ/s640/DSCF2679.JPG)
This shows one with the lathe running - very little run out
(https://lh5.googleusercontent.com/-vipktSuTLAk/UXooNHQ2cfI/AAAAAAAAHhg/WF_6wzkwoXM/s640/DSCF2683.JPG)
The threaded portion is made from a 7BA screw, held gingerly in a collet and drilled thru then 'reamed' using a piece of the piano wire ground at an acute angle as a reamer. This produces a good 'Loctite' fit on the wire. Constant withdrawal to clear the swarf is neccessary as it soon builds up and will jam on the taper.
(https://lh5.googleusercontent.com/-D1LQnJ2eZIE/UXooQarpOmI/AAAAAAAAHho/y6vjzIubcDo/s640/DSCF2686.JPG)
(https://lh5.googleusercontent.com/-aLtaqz4BTYk/UXooTn0g-RI/AAAAAAAAHhw/gar9HjFc3Zw/s640/DSCF2690.JPG)
(https://lh5.googleusercontent.com/-FyZ23_CJW_k/UXooXOCS25I/AAAAAAAAHh4/Jbki4zkGjHA/s640/DSCF2704.JPG)
I finished machining the pistons and contra pistons today so there is just the wrist pins to do then the lapping of piston and liners can get underway.
'Tangler' - Rod, recently requested if I could be more specific in showing the lapping process that I use. Jo has also intimated she'd like more detail for her Crosskill engine. I had actually begun to take some pics to cover this subject to make it as detailed as I can so I think the best thing would be to combine it all together on a separate thread. I will try to begin that tomorrow night.
It's good to be back guys - you just don't know how good that feels :)
Regards for now - Ramon
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Good to have you back Ramon and thanks for this update. Will look forward to the thread on lapping too.
Bill
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Hi Ramon, I have no knowledge of any problems you have had, but I am glad you have reconsidered and returned to us. You have so much knowledge to offer us and I for one would be very disappointed to see you leave. Problems do arise but we must remember that sometimes no matter how small they are they can be turned into a mold hill. Some rules have to be followed and I do understand this.
Remember some of us are grateful for what you can contribute to us. Thank you for your continued inputs.
Don
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Ramon, I always read and enjoy your posts and I am especially looking forward to your lapping methods. There are several high pressure metal to metal fits on diesel ships engines that have to be maintained by micro lapping, so I have had some experience but you have a real knack for explaining machine operations with clear photos and words.
Many thanks for your efforts.
:cheers:
Dan
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Very, very pleased to see you back, Ramon. Looking forward to continued progress on these engines.
--Tim
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So glad you're here Ramon!
:praise2: :praise2: :praise2:
Dave
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Ramon,
I'm very pleased that you are back with us.
Rod
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Ramon ....what you did to support that needle is just brilliant!....just like a Jacot tool!
Awesome my friend!
:praise2:
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Ramon
Nice to see you back, I hope all the problems we had are just memories.
Phil
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I did not see the problems you mention but I am glad you are back with us. Your expertise and explanations are much appreciated.
Jim
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I missed the upset as well. Really glad that you haven't "slung your hook" Ramon. I thoroughly enjoy your threads.
cheers
bp
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I'm glad you're back Ramon.
It was very upsetting to see you go.
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"clear minds have prevailed" Well done Ramon. I'm very pleased to see the continuation of your work. You always seem to have some new trick to show us, for this I thank you. :ThumbsUp:
BC1
Jim
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Hi ramon
Did not know you left, but Im sure glad your back!
A FAN
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I was also unaware, Ramon. The world is as it should be.
Hugh.
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Good to see you back here Ramon, don't know if you got to see my reply in the other thread before it went but would be a pity if the forum lost you as you have a lot to give which we can all learn from.
It would be good to have a separate lapping thread, if for no other reason to save me looking for the various ones on the other forum each time I direct someone there. ;) If its not too much trouble could you include the copper laps as well as the expanding one which I think you are likely to use on these engines.
J
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Please you're still with us Ramon I was beginning to wonder where you were, I learn a lot from your posts, I don't tend to say too much:- that's just my way, but I do look and remember.
Cheers
Stew
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Ramon
If it's not too much trouble, I would love to see a lapping thread.
Vince
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I've just had my spirits lifted by hearing on the radio Bach's Tocatta in Fugue played on strings by the Philadelphia Orchestra and then came through here to find all these replies. What can I say - I'm totally overwhelmed. I don't think I need say anymore than just simply thank you for all your kind words of support. I think you must know how I feel - it will certainly not be forgotten.
It's best now though that we move on - I'll be back later :)
Regards - Ramon
PS will PM you later Jason and respond to the other PM's too
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Ramon,
Glad to see you back, best wishes,
Simon.
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Glad to see more posts on this Ramon and most pleased you're still here.
Cheers
Steve
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Ramon,
So glad you chose to stay on here. Like many others, I have no clue about the issue, but I can tell you that I learn much from your posts. And you always seem even keeled to me in all your posts; just offering your experience to a conversation. I find your explanations very clear and understandable. I learn much from what you have to say.
Thanks for taking the time and effort to share with us!
Great work on the needles! Very interesting. And I will add my voice to the chorus of requests for a thread on your lapping technique! :)
Thanks Ramon,
Kim
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Hi 'Guys' - Just to say I'll be back on the main computer tomorrow.
Have took plenty of pics today and all the cylinders are lapped and the pistons and contra pistons fitted but I'll leave those pics for the other thread. Had a good clean down - it's a right messy op is lapping ::) and set up ready for the final assembly. I just have the wrist pins to make but I'll do then per assembly and tackle the anodising in the next day or so. Hopefully they'll be ready for a run next week ;)
Heres a pic of the bead blasted parts - I think you'll agree it does make a nice job of it
(https://lh6.googleusercontent.com/-Wdz00klX7NM/UYllEYgH7gI/AAAAAAAAHrc/DRR1guue6Lo/s640/DSCF3017.JPG)
And all the parts ready for assembly - always 'the nice bit at the end' :)
(https://lh3.googleusercontent.com/-cpNCqm9USnE/UYllBQ4U5UI/AAAAAAAAHrU/bDNvji4arPY/s640/DSCF3015.JPG)
I shall sleep well tonight ;)
Regards for now - Ramon
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Pretty amazing work there. Looking forward to the run.
I'm still kicking myself for not having picked up the blasting cabinet when I had the chance.
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Will have to look at getting a blasting cabinet, those engines look amazing. Looking forward to seeing them assembled. Keep up the great work.
Paul.
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They look very professional Ramon :ThumbsUp:.
I bet you are looking forward to getting them together to give you a bit of bench space again ;).
Jo
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Those look great Ramon!.... :ThumbsUp:
Dave
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Hi 'Guys'
As always thanks for your interest.
Jo you'd be right there - the next project is going to need quite a bit of space ;)
Thought some might like to see a few pics of the piston making - the lapping of 'em will be on the other thread....
They were turned from some 1" cast iron bar bought from 'Noggin End' - no connection just satisfied. The bar was lovely to machine - very uniform and was taken down to 20.0mm diameter long enough to make the four pistons and contra-pistons.
The ODs were turned to 18.5mm and the inside drilled and bored to depth. The inside diameter of the skirt was then relieved to 16.5 mm to fit on the turning fixture and the whole parted off before transfreing to the mill to have the wrist pin hole drilled and reamed.
Once to this stage the internal profile could be milled first setting the wrist pin square to the table.. This was acheived by holding a slip block against a dowel in the wrist pin hole and squaring up to it by using the rotary table to align it
(https://lh6.googleusercontent.com/-dWoraf_SsME/UYllr0ghVDI/AAAAAAAAHrs/pLQV-637IMU/s640/DSCF2773.JPG)
Oops just hit the post button ::)
The major slot was milled by plunge milling in 1mm steps - the slip and dowel was removed first ;)
(https://lh6.googleusercontent.com/-AJO48UFZFI0/UYllpIU8SOI/AAAAAAAAHrk/59BbWl2cfOY/s640/DSCF2770.JPG)
To lighten it as much as possible the corners of the bosses were relieved .....
(https://lh3.googleusercontent.com/-xrqR263iMic/UYbDW_8ZM3I/AAAAAAAAHlc/EzxZBJkEJlc/s640/DSCF2791.JPG)
Before popping back in soft jaws to turn a relief at the top
(https://lh3.googleusercontent.com/-cZrHJJKPz5g/UYbDZ29R_9I/AAAAAAAAHlk/X1oXXpXMSR0/s640/DSCF2795.JPG)
Once this stage was reached they could be mounted on the fixture.....
(https://lh5.googleusercontent.com/-Bot-AJJneKc/T_HQ_M6njHI/AAAAAAAAGk8/2UMnTqBWFUk/s640/DSCF0798.JPG)
..... for finishing the ODs and turning to length
(https://lh6.googleusercontent.com/-sDCNE_9H0ks/UYbDcqKdYiI/AAAAAAAAHls/Iwiu0Mdow6E/s640/DSCF2800.JPG)
The contra pistons were all bored to fit an expanding mandrel used in reverse ie the expanding screw removed and the spring of the jaws used to provide the gripping power. This is sufficient to resist turning forces for turning the OD, facing and the turning of the cone recess. Once finished to fit a liner the wall thickness will be reduced.
(https://lh6.googleusercontent.com/-d3_JesPly-I/UYll8LYIzdI/AAAAAAAAHsc/phcfqAFJL1Q/s640/DSCF2807.JPG)
And all done ready for lapping
(https://lh4.googleusercontent.com/-ngemlttQfMc/UYll-iYkR6I/AAAAAAAAHsk/-OIvcbxn6dI/s640/DSCF2812.JPG)
Assembly began today along with some anodising. The lower ends all went together with a minimum of tweaking just a couple of the bearing housings proving slightly too tight. Hopefully if all goes well they could be together tomorrow ;)
Regards for now - Ramon
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Ramon, I notice your piston turning fixture places the work a long way from the chuck, is there any reason for this? Or do you make it long to start with and take a bit off to true it up each time you chuck it and the longer length gives more uses.
J
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Morning Jason - yes looking at the image it does appear to have rather a lot of overhang. Took a look at it this morning - the reduced portion is just 35 mm long and it is as you say for recutting the seating for each piston(s)as well as allowing the lap or hone to pass - the last one had got far too short for that to happen.
The pistons, by the stage you see it here, have only a small amount to come off - in this case 18.5 to 17.95 - so far no chatter has been experienced even with this bit of overhang.
Just finished the first wrist pin so am about to assemble the first engine ;) The anodising didn't go quite as well as hoped for - more on this a bit later but for now, it's back to the comfort zone :)
Ramon
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Hi 'Guys'
Thought you might like to see this ;)
First engine assembled is the Elite Mk2 ( the original was all 'self coloured' - no anodising on this one)
(https://lh5.googleusercontent.com/-PD0sEu5qkQA/UYuDB4vmORI/AAAAAAAAHvk/uxePITIliKg/s640/DSCF3040.JPG)
(https://lh5.googleusercontent.com/-bNTmi_sIVAg/UYuDFEgloSI/AAAAAAAAHvs/kZJrmRUflVM/s640/DSCF3045.JPG)
(https://lh4.googleusercontent.com/-VQDbmFCowTM/UYuDIUvfLDI/AAAAAAAAHv0/qwwTzl2fPXo/s640/DSCF3046.JPG)
Hit a small problem with the piston skirt hitting what I first thought was the crank web - after taking off a mil on diameter it was catching on the top of the front housing register ::) a quick stripdown and a step milled on cured that. The only other hiccup was the comp screw - all of these were screw cut to their respective heads to ensure a good fit but this one did not want to go in bar a few threads - it would go in the other heads okay and the others would fit but this wasn't having any of it till I ran a well opened up die down it :???:
Anyway the thing you really want to know - is yes it did :)
(https://lh6.googleusercontent.com/-xx6hLwmEDas/UYuDLZAF0tI/AAAAAAAAHv8/5GPoZ5cgmJA/s640/DSCF3053.JPG)
(https://lh5.googleusercontent.com/-kuRJu2X0w0E/UYuDOSYkrlI/AAAAAAAAHwE/HrbXGjhLUnI/s640/DSCF3054.JPG)
Didn't take long to find the settings and once found it was away - revs kept well down at this stage - prop is the usual 'first run' wooden 12" x 5" and the fuel kept nice and rich. Couldn't run it for long as my neighbours house is only about 50 feet away directly behind the workshop. They are pretty tolerant but I don't like to over do it. However with the comp well back it did have a gorgeous intermittent diesel 'crack' to the exhaust note
Well that's the first one done - three more to go - had much better success on the anodising only to spoil it when distracted by the crank/piston problem - ah! Sue's right there then - I can't multi- task ;)
More on that a bit later - I'm off to concentrate on the anodising and see if I can get it right this time ::)
Regards - Ramon
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Well done Ramon :ThumbsUp:, I wish I could say the same about the R&B :-[
Jo
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Good to see one going Ramon and by the looks of the "Gold Top" in the background the anodising is comming along. Also looking forward to seeing the silencer that you mentioned to me.
Are the cross head screws commercial ones, modified commercial or completely made by you? if the latter I would be interested in your method of cutting the cross slots.
J
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Wonderful. Thanks for sharing.
Rod
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Sue's right there then - I can't multi- task ;)
Regards - Ramon
Very Nice Ramon :NotWorthy:
Regarding the above. Galina tells me the same thing. My response is. "I know this is one of the shortfalls of the male, however that means I apply 100% to the task in hand - remember how well I chose when I chose you." :cartwheel:
Best Regards
Bob
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Sue's right there then - I can't multi- task ;)
Regards - Ramon
Very Nice Ramon :NotWorthy:
Regarding the above. Galina tells me the same thing. My response is. "I know this is one of the shortfalls of the male, however that means I apply 100% to the task in hand - remember how well I chose when I chose you." :cartwheel:
Best Regards
Bob
I like that one Bob. I'm going to have to remember that one.
Cheers :cheers:
Don
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Hi again 'Guys'
Jo - hang on in there you will get there in the end and it will be all the more satisfying :ThumbsUp:
Jason, the screws are commercial stainless 6-32 Philips pan heads modified to look like the original engines round head versions.
Contrary to virtually every other makers engines - if not all - the Eta 15s had these roundhead screws - everyone else used slotted cheese head - It did look strange at the time compared to others but I feel it now adds a certain character. I found impossible to get stainless Philips R/H hence the mod.
The Mk3 was assembled next and I managed to give it a run this afternoon. About the same as the Elite earlier not quite the crack and much steadier with the compression backed off. I only ran it long enough to get a couple of pics .....
(https://lh6.googleusercontent.com/-Jtyp-gvtrYw/UYv1yCvuevI/AAAAAAAAHwU/RIiwDFBR8CQ/s640/DSCF3059.JPG)
Anodising the two Elites has not been without a few problems mainly based on using gold dye for the first time. However I've learnt quite a bit today - As you can see above the blue on the Mk 3 went quite smoothly but but the gold was a real pain. I did some test pieces first and acheived this lovely pale gold which was just right.
(https://lh5.googleusercontent.com/-gNn6yXjWx_E/UYv-cVeIbkI/AAAAAAAAHw8/HtJNsTfsa1I/s640/DSCF3027.JPG)
(Yellow was tried to just to see if it looked 'gold')
One head, prop driver and spinner then went in together and appeared to have anodised okay. They all went in the dye together too and this was the point when I was distracted by the problem with the piston hitting the register. Oops :facepalm2: they were left a bit too long and that pale gold turned into a much deeper shade - nearer bronze. No pics as yet but as Jason noticed you can see it in the background. For some reason the spinner appeared not to have been degreased thoroughly and was a complete disaster so was set aside while the same three parts for the second engine were done. This time the parts did not seem to anodise as well and despite a long soak they would only reach a 'biscuit' colour and two varying shades at that.
Heres some of the 'disasters'
(https://lh3.googleusercontent.com/-Az8xr2neBSs/UYv-eyuMi2I/AAAAAAAAHxE/AaD8Nk8hhew/s640/DSCF3065.JPG)
After some thought it was decided to keep the darker shade as is and try to match the spinner from a second attempt. I had not tried to remove anodising before but knew that a soak in hot caustic soda solution was recommended. Got this heated up and in went the part - nothing happened at first then suddenly it 'burst' into action bubbling and fizing like mad. It was washed clean before degreasing as usual in washing soda solution and re-anodised. Lovely uptake of colour as close a shade as mattered but left it in the steambath too long without turning it - the colour leached out on one side - Another case of 'Golly Gosh' - isn't this fun :facepalm2:
Stripped the 'biscuit' coloured parts and re-anodised and this time getting a good shade of gold but time was pressing at this stage and dinner was on hold :o - I'll take some pics tomorrow.
Things learnt ? Gold appears to need more care than other colours. Hot Caustic Soda solution really does strip the anodising off. It also puts a lovely matt finish on which the anodising does not seem to affect - colour then is flatter than usual. The process though could be used to apply a dull smooth finish to self coloured parts - I did think about leaving it as was but it didn't look right. Colouring the last parts I left the driver in the dye as it seemd slightly lighter than the head. In the time it took to pop the head in the steam bath the driver had increased in colour. Aagh - but I tried putting the head back into the colour - after the soak in the steam bath to seal it and surprisingly it took up more colour - something well worth knowing for the future
Sorry for the lack of pics - it's been a busy day :)
Regards - Ramon
Bob - I'll save that one ;)
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Some really nice engines (again) :)
Glad you stayed and show us - any chance of a video (with the glorious noise) :Love:
Best wishes
Per
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Yes Video would be wonderful....
Dave
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Yes Video would be wonderful....
Dave
Agree we need it.
Ramon when you have finished with your lapping thread, would it be much trouble to make one on anodizing?
Don
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yes!
That would be great...but I don't want to "kill the golden goose"....so to speak
Do what you can Ramon...I am thankful for what ever you can contribute!
:praise2:
Dave
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This was an educational build log Ramon. Great engines. Thanks for the journey.
Vince
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I would enjoy an anodising thread too, if possible. These engines, however, are a joy to behold.
Hugh.
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Amazing work Ramon, absolutely beautiful! Thanks for sharing your knowledge. :ThumbsUp:
Kind Regards.
Ewald
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I've been following this build all along, and I'm very glad you stuck with us, Ramon. So much interesting and useful information here, and great engines at the end!
Simon
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Hi guy's thanks for all your kind comments however it's not quite the end of the road yet.
All four engines are finished - just - and all have beeen run - back later with some final pics and details
regards for now - Ramon
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Ramon, threads like this one are what dreams are made of. So much useful information to digest and then there are the pictures to drool over :P as well. Those engines are truly works of art, with or without the colors added. :ThumbsUp:
Bc1
Jim
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Ram on, wot Jim said. These are Picassies in metal :praise2:
Yo Redneck,
Eric
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Hi again Guys
Another computer failure tonight :o but this time I think I finally traced the cause - apparent glitch in the power cable. The computer just 'clicks out' giving a total loss of signal but the strange thing is when the switch is pushed on the unit nothing happens except the fan goes into over drive like the kitchen cooker hood on full drive :???: At some stage pulled the power plug (from the computer) and replaced it and everything went back to normal :???: :???:
Oh well better late than never - wonder if that will cure it the next time?
It's been another long day - I tried again, without success, to match the colour of the Elites on the spinner nut's so in the end accepted the dye had probably been depleted and after taking it off with caustic - again - the nuts were polished up to remain 'self coloured'. However as mentioned earlier all the engines are now assembled and have had a quick run - one or two little probs but all over come and I'm pleased to say I well chuffed with the results .....
The first Elite was given a quick run on assembly but it soon became apparent that the contra piston was way too loose - it seemed tight enough when pushed in but as soon as things warmed up on running you could hear it rattling. A quick strip down revealed it sitting on top of the piston and it just fell out - I guess it lapped itself in :D I've mentioned this before but it's worth repeating I guess but if you overshoot the size on a cast iron piston or contra piston if it's heated a good cherry red for a couple of minutes and quenched in oil it will grow a little. This one gained a good 0.05mm but that does include the carbon!
(https://lh4.googleusercontent.com/-DjW8cet_lUc/UY1JVOzSpqI/AAAAAAAAHys/6HdTNeJKslg/s640/DSCF3083.JPG)
(https://lh5.googleusercontent.com/-CV5RTkpZrJ8/UY1JYOe3Q3I/AAAAAAAAHy0/WTOnuTCICt8/s640/DSCF3085.JPG)
Lapped down using two stones as before it was test fitted a couple of times to get the fit just right and it was back up for a run - and much better this time
(https://lh6.googleusercontent.com/-rSsX6LYOcUM/UY1JR2JFGtI/AAAAAAAAHyk/9dV-sA5WJKI/s640/DSCF3080.JPG)
Incidentally - when first assembled it was very tight just at the top of the stroke so it was stripped and re-lapped - I used a much finer compound and achieved a truly superb seal - more on this in the lapping thread when we get to it.
The second Elite was the last to get done and for some reason this one exhibited a tendency to kick backwards and run in reverse - it did this intermittently when suddenly it came to an abrupt halt. A careful but anxious strip down revealed the L/H threaded rotor pin had unscrewed until the head of the screw had fouled the conrod. This was reset using some thread locker and the slight scarring on the rod removed with a needle file and a polish with ScotchBrite. No harm done so it was back up for another go
(https://lh4.googleusercontent.com/-ty6voZgvbb0/UY1Ja0cfLEI/AAAAAAAAHy8/ic4mx8cXvg0/s640/DSCF3090.JPG)
Given the proximity of my neighbour it's really unfair to run these for more than a few minutes and well backed off at that but the temptation is there to turn the comp up and the response to that is encouraging - I appreciate your need for a video - I will have a word with him and explain so hopefully we'll have something in a day or two - won't be till Monday though ;)
When I set out to make the Mks1&2 a year or so back I had harboured thoughts of being able to produce the series but at the time could not see the way around making the crankcase. The idea of making the silencer register a separate part came into my head on holiday so see it work out as it has has given a great deal of satisfaction.
Heres some better pics...
Mk3
(https://lh5.googleusercontent.com/-0D4skjtszpA/UY1JgxAIbTI/AAAAAAAAHzM/Y3H-xPxjnyI/s640/DSCF3112.JPG)
Elite
(https://lh6.googleusercontent.com/-Xxe65w1xb9o/UY1Jd-wtWsI/AAAAAAAAHzE/BpwRlOTrEIA/s640/DSCF3106.JPG)
Elite Mk2
(https://lh3.googleusercontent.com/-n_U2NSaLuP4/UY1Jj2CyyuI/AAAAAAAAHzU/fwU6WhPx_FI/s640/DSCF3119.JPG)
This is the series Mk1 to the left - Mk2 to the right at the rear .....
(https://lh3.googleusercontent.com/-yxN8XCrBKVg/UY1JsZ6E1lI/AAAAAAAAHzs/T1YEGdIZnhs/s640/DSCF3137.JPG)
...... and this is the 'Stockton and Jehlik' version - a heavilly modified Eta 15d full details of the modifications of which were published in the 'Aeromodeller' magazine circa 1967
(https://lh6.googleusercontent.com/-Qi-zzp7SqFU/UY1JvZpTYyI/AAAAAAAAHz0/tXOWFW3U-gM/s640/DSCF3142.JPG)
It's not quite the end of the road as the Mk 3 onwards had the possibilty of fitting a silencer so it's intended to make just one as an 'accessory'. It's quite complex consisting of eleven separate parts but should make for a nice machining exercise :).
Well I really think that's about it on this thread for a while - As said all the lapping of the piston and liners will get dealt with on the other thread - it was my best intention to try again on that tonight - I'm, truly sorry to say but it's been a long day again and "Mrs Wilson's little boy is a tired little boy at that" - Definitely - most definitely tomorrow :)
Before I disappear though I must say a big thank you to all who have followed this thread and particularly to all who have posted and made such kind comments at times. It takes quite a bit out of the day to get this up here and it's nice to know at times someone is reading it. Thanks indeed - it is appreciated.
Regards for now - Ramon
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What a beautiful set of engines! You have inspired me again Ramon, as I can just dream of producing such outstanding pieces of craftsmanship. Very well done and very well presented. Thanks you.
Don
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gorgeous work Ramon!
A hard act to follow but very inspiring all the same.
Pete
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A stunning set. What do you call that? A 'gaggle' of engines?
--Tim
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Absolutely Ramon!
:praise2:
Dave
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I can understand that writing this up does take a bit out of every day. That, coupled with the actual making, mustn't leave too much time for other things. Thanks for your generosity in making these posts.
Hugh
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Hi Ramon
I'm a little behind with my comments as usual; but wow! What a completion to a wonderful and very interesting project; I have enjoyed very much following along with your ingenious setups, machining techniques and attention to detail.
I'm glad you decided to stay on MEM and look forward to seeing what the next masterpiece is that will come out of Ramon's shop.
Best regards,
Dave
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Wow - they've really come out superb Ramon
Steve
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Ramon,
After making so many engines on the same theme it looks like you are ready to get going on that radial of yours :ThumbsUp:
I personally get bored with too much of the same: Don't talk to me about studs :disappointed:
Jo
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:NotWorthy: Wow what a family portrait :NotWorthy:
Ramon, I heard a few references to the 'Stockton and Jehlik' version over time and I figured the part about the Cox front being the rear induction, but I haven't seen any pictures or explanation about the compression adjustment changes - is it a fixed squish band with a smaller diameter (than the piston) adjustment of the compression chamber ?
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Glad you like 'em 'guys' and that you've enjoyed the build. You may recall I said at the beginning that I was asked to write an article for the Model Engineer magazine about them - well it's about 60-70% done and now I really must devote the time to finish it. It will cover building the Mks1 and 2 along with full drawings - assuming they still go ahead with it - as well as plenty of pics.
I hear what you say re the Bentley Jo but it's not on the cards yet I'm afraid ::)
Admiral-dk - The Stockton and Jehlik 'Eta' engine was more S&J than Eta - I think the only thing originally Eta was the crankcase along with the piston and liner and the crankshaft (and even that was slightly modified to take a K&B spinner.
The rear drum valve induction was quite an inovation at the time and for team race engines a real ground breaker, many specialist (2.5cc team race) engines using a similar or improved version of it virtually to date. The black plastic moulded case came from a Cox Tee Dee 049 on the original but was machined from solid on the version above. Incidentally - the venturi and needle valve system, also off the same engine was brought round by a friend and I measured it while he was here. 'Scaled up' and drawings done it was only after it was assembled that it appeared too small and out of scale. I borrowed the engine again and the mistake was quickly spotted - I must have inadvertantly re-zeroed the digi caliper as I was measuring as all dimensions save 2 were out by 0.8mm :o Needless to say it all had to be made again - the small undersize version sitting here as a salutary reminder.
Wrong 'uns are on on the left !
(https://lh6.googleusercontent.com/-vf5Fs2AdB5o/TgT2AYfUPvI/AAAAAAAAFSg/WrJ8NKj1Qfk/s640/DSCN3261.JPG)
The contra piston is indeed a composite - the moving part is around 12mm diameter in a 17.90 bore. The major part a tight fit in the head and giving a squish band as you state.
This is the only image I have of it - it is to the right of the crankshaft inthe foreground parts
(https://lh5.googleusercontent.com/-jM-VgXPsAH4/TfzpUJj0gNI/AAAAAAAAFRQ/6NTxXywcemM/s640/DSCN3234.JPG)
It was the first engine I have used with such an arrangement and the compression control is very fine indeed but it does have a different sound for some reason sounding at first undercompressed when indeed it was over. Once that was realised however it does run really well.
In case anyone was wondering the usual tommy bar type compression screw was replaced with a allen head screw - I don't know about at the time circa 1965/7 but tommy bar screws are no longer allowed on safety reasons. This was the only area that was a guess - no details were given and there are as far as I'm aware only a couple of photographs of the original engine and this is quite indistinct. There is also some thought that it may have been a system that directly contolled the contra piston - often referred to as push/pull where the contra piston is retracted by the screw as well as advanced.
The arena of Team Racing has probably done more to advance the improvement in power and efficiency of these small engines than anything else. I know relatively very little about it save for being on the periphery of it when flying control line aerobatics and whilst a dyed in the wool 'aerobatic die hard' the TR fraternity are very much my 'aeromodelling heroes' Another 'oh for one more lifetime' moment ;)
Regards - Ramon
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:praise2: Thank you very much for the clarification - I've never seen the original article - so this really helps me understand how it's done :praise2:
Sorry but after looking quite a bit again - the part to the right of the crankcase looks like the propdriver to me - It's knurled, doesn't fit inside the cylinder either as far as I can tell - are you sure the part we're talking about isn't already "buried inside the head / cooling jacket" :noidea: ?
I didn't know about the Tommy Bar being banned either - does that only apply to Team Racers or are this a general thing ?
Best wishes - Per.
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Bentley Bentley Bentley Bentleybentleybentleybentleybentley :'(
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Ha Ha! Nice try Pete :D - it could be a while yet though ::)
Hi Per - I thought for a second I'd had a 'dyslexic moment' but I think you may have read 'crank shaft' as 'crank case' ;)
The contra piston is just behind the piston to the right of the crankshaft which is bottom left - the contra piston itself has a spherical chamber and is in actual fact 11.2 diameter.
I'm not certain when or exactly why the tommy bar rule came in but as far as I'm aware that is the norm now - for competitive team racing only. Whether the safety reason was one of injury - pilots catching the model at pitstops ? or of the potential of catching lines I don't know.
Regards - Ramon
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I thought for a second I'd had a 'dyslexic moment'
No you don't, but I do - or more correct :
I was extremely dyslexic as a kid until my parants in desperation decided to do something about it and send me to a specialist in "Christian Wolfs Method" (a Dane who was completely discredited by his peers), where I was tested with a number of different (some of them weird looking) tuning forks, put on different parts of my body and I was asked about how long the sound traveled through my body. All this was entered into a schedule and resulted in a single record (EP ?) that I must listen to on headphones for 10 minutes every day for six months :noidea:
I absolutely did believe it was all a scam (no placebo effect), so imagine my surprise when I after some 5-7 months starting to note when I wrote something wrong and started to be able to read fast instead of taking for ever to try to decipher a sentence :whoohoo:
It gave me a new access to a more or less hidden world :) and I'm not the only one "curred" this way. I'm still slower at writing than most, because I need to correct a good deal of my writing - thank God for computers and wordprocessors :whoohoo: - spellcheck is a nice addition to this, but I feel rather good if writing all this here and I don't get any errors (it happens now and again) ;D
I spotted the right part after your last post - it looks a bit like an upside down button with a concave (or is it convex) depression (dome) that must be the moveable part - thanks :praise2:
Best wishes - Per
ps 3 spell errors found by Spell Check - oh well ;)
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Sorry to be a pain - but have you talked to your neighbour about noise and a video ?
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Hi Per - no you're not a pain at all but one or two things have got in the way - article, lapping thread, garden, sailing, the enemy, oops sorry I mean the mother in law, Sue on holiday to name but a few ;)
I haven't forgotten the requests for one however and will do it first chance I get - promise
regards - Ramon
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Hi again Guys
Thanks to Pers reminder I made the effort today but truth to tell it didn't go too well ::)
I set the Elite Mk 2 up for running with Sue on the camera and within a couple of flicks it was away only to abruptly stop. Something was definitely not right :o . Taking the backplate off I was very surprised to find the head of the rotor pivot pin had sheared off at the thread undercut. Amazingly no damage appears to have been done.
I can only assume that maybe this was a bit too hot on heat treatment and perhaps the first to be quenched in the cold oil. It was certainly well tempered. I have seen this at work - particularly on silver steel - we used to heat a small piece of steel at the same time as the parts to take the chill off the oil in cold weather - who knows? Flame heat treatment at home is such a guessing game. I shall remake the pins from En16T and not heat treat them. This should be more than adequate for the amount of running they will get but a hardened surface would have been preferred.
For some reason unlike the Mk1 and 2 (which ostensibly have the same timing) these engines appear to have a habit of firing and running backwards - on the second engine tried (the gold headed Elite) this happened and spun the screw loose again - these will definitely require fitting with thread lock.
So - you'll have to settle for the 15d Mk3 and a poor video to boot I'm afraid - the focus appears to be slightly out and no way does the sound capture the bark like my ears do. Once these screw problems are sorted however I think these will prove to be easy starters and powerful runners. It does help when you have the fuel tube connected to the spraybar though :facepalm2:
https://www.youtube.com/watch?v=6vn8o8IHm7U
They'll need quite a bit of running before a 'decent' size prop can be fitted to let them really have their head - have no idea when that'll happen though
I've decided to leave the silencer for a while, currently I'm building a 'correct' 2.5cc size version of the Stockton and Jehlik modified engine but after that I shall be taking a break from machining for a while.
Hope you've enjoyed the journey as much as I've enjoyed posting about it - I'm also near finished on the article for Model Engineer and will have that off to them within a few days.
Back soon with a few pics of the S&J - it has a very challenging cylinder head to turn - 0.6mm fins with a 0.6mm gap 7.8mm deep.
Regards - Ramon
Edit - just realised there's a 'you tube' link ::)
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That is pretty cool Ramon! Your 15d Mk3 seems to run great!
Sorry to hear about the mishaps with the other engines, but I'm sure you'll get them working in short order.
Thanks for sharing the video!
Kim
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You're welcome Kim, glad you like it. It's the best of a bad lot I'm afraid - surprising how long it takes to upload such a short clip too.
The engines will be back together again today - I'm off to make new screws ::)
Ramon
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Great video Ramon, and a beautiful collection of engines as well. Having played around with C/L planes and glow engines as a kid, I am amazed how easily yours starts...more a testement to the quality of the build no doubt!!
Bill
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Ah Bill - it's all in that well practiced 'flick' ;) - I wonder how many times I've actually done that over my life :)
I've certainly had one or two that were a real pain to start but overall they've not been to much of a problem - it's more technique than anything I guess.
When flying control line aerobatics you had one minute to start the engine, get to the middle of the circle and take off. With only a seven minute flight from first flick to touch down and come to a stop, the longer it took the closer you got to an over run.
The engines (all glow) were expected to start first flick - after three something was usually wrong and the old anxiety levels rapidly kicked in so a technique for each engine was quickly developed. Ah - happy days. Hmmm on that note - am I allowed a little indulgence?
Taken just after I left the Army around 1967/8 the guy helping is a life long friend - Colin was my Best Man when I married Sue
The aircraft is an Italian design the drawings scaled from a three view in the Aeromodeller Annual. Engine was a 6cc Merco 35. It was my first big 'stunt' model.
(https://lh3.googleusercontent.com/-TPRyA82VjHg/UaXrVRkUHNI/AAAAAAAAH3g/VcZXXULPQwQ/s405/I-Baga%252003.jpg)
Many years later - 2006 to be precise, and a proud moment having just made the winning flight in very windy conditions for the Classic Aerobatic trophy at the UK National Champs. The model, my all time favourite and my last but one build, is an American design - The Thunderbird Mk 2 designed by Bob Palmer. Engine was a very smooth running Italian Super Tigre G21/46 rebuilt from a sorry looking R/C motor - a ten pound purchase at a swapmeet. It was to be the last year I flew a model of any kind.
(https://lh4.googleusercontent.com/-PDnKkXjWdx4/UaXrVzxbwsI/AAAAAAAAH3o/57rgeAqyEXo/s512/Tug%2520and%2520TBird.jpg)
Yes - definitely happy days ;)
Apologies for the nostalgia
regards - Ramon
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No apology needed Ramon, thanks for the added pictures too. My involvement was never from the competition side, just afternoons in the schoolyard with a few high school buddies...mostly Cox .049's which at the time could be had new for around $4.95. We did later get up in the higher displacements (.15 -.35 or so) but it took a lot more room and those wire control lines were a pain to keep unkinked. You're right though, good times for sure and far more innocent times as well. Sadly if it were today, I doubt we would even be let on the schoolyard for fear of liability issues, etc.
Bill
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Nicely done Ramon. Sorry to hear about the problems with the other two but it seems you already got them sorted out. Now I know why you always make three specimens. :)
:cheers:
Vince
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Ramon
could you clear up a point for me in my long lost past I used to fly a near scale Spitfire C/L fitted with a Mills 75
is it true that these engines pistons were tool steel lapped to the bore at the factory ?
Stuart
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Yes - definitely happy days
Apologies for the nostalgia
regards - Ramon
Not at all Ramon....thanks for sharing that!
Dave
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Careful Dave - I've been known to wax lyrical over these things for hours ;D
Stuart as best I can say you are correct. The Mills 'heyday' was just before my own Aeromodelling initiation but I do recall adverts from back issues of the 'fifties Aeromodeller magazine that I later collected that covered the various stages of manufacture of Mills engines.
I'm pretty certain they made claim that all the liners were heat treated and ground to a high tolerance (to anyone elses ?) and the pistons too. These were then checked using a highly accurate 'fluid measuring device' to precise limits and were then individually fitted to a suitable liner. I certainly remember wondering at the time about the 'fluid measuring device' and still do - never seen one and can only assume they work on displacement.
Control line flying has always been my 'achilles heel' as far as other modelling is concerned though I do believe it has run it's course now. To compete these days means lengthy journeys from where I live and to be truthful it's difficult to justify the cost for the usual three flights or so. Plus with nowhere to practice these days - and it does take constant practice - it's best to let it go and remember the good times. Sue and I have extremely good memories of our time with the 'stunt fraternity' - members of CLAPA in the UK - and often reminisce about it - as said, very happy days indeed.
I still have four airframes left however - just in case you see ;), three ready to go though I suppose gradually deteriorating as they hang in the garage unused and one requiring painting. All the parafernalia that goes with it is in the 'old stunt chest' up the loft ;) and I still hang on to several engines (as you do ;) ;))
This was the 'fleet' about 2005, all scratch built from plans the front three having gone, the Nobler and Oriental sold on but the Master in the foreground was lost due to a control failure (poorly soldered joint) in 2006
(https://lh6.googleusercontent.com/-VImonq_XzPo/UaY51pFdfSI/AAAAAAAAH38/3Z2h8AkX1zQ/s640/2005_0522Image0025.JPG)
The silver Nobler saw many comps and came through unscathed. It made it's last flight just as the T'bird was ready to go and I remember well, despite countless flights, the dry mouth feeling on that last flight before retiring it incase anything went wrong and it would go home in bits.
They are all conventionally built from balsa, tissue covered and painted. The lack of paint on the wings on all but one was in order to keep the weight down. The two Noblers are the smallest - wingspan - at 50.5 inches the Oriental is 52(54?) the T'Bird 55 and the Master 56.
The engines? the Oriental and silver Nobler have OS35S's, the Master an OS LA46, the second Nobler had a Ukranian built Stalker 40 (truly superb engine and made specifically for purpose) and the T'Bird the Super Tigre mentioned before. The engines in these models are required to run at a steady rich setting in level flight - universally but eroneosly called 'four stroking' breaking into a faster two stroke as the nose comes up to give power through the manouevers. (no throttle control remember) This '4-2-4' running characteristic is not something that most engines will do without modification to the timing though the Fox 35 and OS 35S would do it out of the box. Head shimming, fuel and venturi size played a big part along with a good fuel tank set up too.
Ah stop he said - you see what I mean Dave ;)
regards - Ramon
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Raymon
You can go on all day if you want with your trip down memory lane. I enjoy it immensely as I have enjoyed all you posts on building and lapping your engines. It reminds me of my days of R/C activity with airplanes, cars and boats in years past. They are days past that we will never live again but they will always be in our mind ready for instant recall and enjoyment. :praise2:
Now put the pen down, throw an oily rag over the lathe, take Sue and go out and do some sailing and catch some sun and breeze. :stickpoke:
Cheers :cheers:
Don
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Honored to be taken along a trip of nostalgia. Much like being invited to someone's home.
I've enjoyed your posts like all the others. Keep them coming. But don't forget your other 'interests'.
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These were then checked using a highly accurate 'fluid measuring device' to precise limits and were then individually fitted to a suitable liner. I certainly remember wondering at the time about the 'fluid measuring device' and still do - never seen one and can only assume they work on displacement.
Ramon,
Try a search under "air gage".....Federal makes them amoung many others.
Dave
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Thanks Ramon for the info a bit more than I remembered
Stuart
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Hi Ramon
Thank you very much for the video and the pictures + tales of your wonderful models. I'm sorry to hear of your problems, but it just shows that we can newer take anything for granted in our hobby - certain IC engines have mind of their own :old:
I never had much success in my youth - several hours flicking the prop = less than 60 seconds of combined running of engine => no flying - or more correct I flew a combined 15 minutes during two years.
I kind of now knew back then, that I had fuel problems, and now I know for sure that this was the main issue along with wrong info on how to do a correct run-in of the new engine + you and a few other youtube videos has shown me that port priming is a lot more important (and require bigger amounts) than I realized back then.
Best wishes
Per
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Thanks for the suggestion Dave - checked it out and another example of learning something every day.
I would never have believed that the 'fluid' was air pressure. As some one well versed (or rather, was) with pressure of gases from diving days I find it quite remarkable that the fine movement involved can lead to a detectable variation in pressure. I guess I'll have to stick to my DTI and Bore gauges ::)
Per - you were not alone - your post brings back memories when as a youngster I was with a friend who had a new DC Bantam .8cc glow engine in a KeilKraft Firefly. It was a freezing winters day and we were in the middle of a rough patch with snow on the ground trying to get this thing to start using a dry cell battery. That little 'Quickstart' spring became a major hurdle to overcome with frozen fingers not to mention constantly taking the plug out as we continually flooded it. Not sure why we gave up in the end - the engine or the cold ::)
Zee, Don, thanks for your comments. Sue had a chuckle at my expense to your remark Don so I promised to take her out - to the model shop of course :Lol:
Regards - Ramon
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Actually the technology has been around since at least the late 40's...though it's gotten much better. Some of the very best ultraprecision machine tool spindles float on compressed air ( groove compensated aerostatic spindles).
Just another fairly useless piece of information stuck in my head.... ::)
The DTI works just fine....
Dave
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To try and overcome the problems inherent in oil operated hydraulic governors, I was lucky enough to be at Maidenhead when the RN was playing about with a fluidic governor, having no moving parts and being supplied with low pressure air as the operating medium. Mind you it was quite a large lump of metal and I think this was the principal reason for abandoning the idea.
Inside looked like something that a bored colony of worms would concoct.
Oh! and before I get tooooo far off track.................beautiful aircraft Ramon. :praise2: :praise2: :praise2: :praise2: :praise2:
Best Regards
Bob
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Ramon,
Really nice work there, can't remember whether I've said before but the first thing I ever tried making was a 0.8cc sparey compression ignition engine - needless to say I didn't get very far - not a good choice for a beginner! Strangely one of the elderly gents in our club did something similar - he's now made all sorts of great models and I think recently went back and re-made the sparey with his new found 50 years of experience and talent! He's also recently completed a 15cc V-Twin - L W Chenery which like yours looks like a work of art but he hasn't started it yet - keeps saying he hasn't got around to it yet but think he's a bit nervous of trying! He has just started having a go at the V8 aero engine by Eric Whittle too which is looking good.
With the compression ignition engines, do you wind the screw in to push the contra piston down giving a high compression to start with and then wind it out to lower it as the engine heats up?
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Hi Nick , theres been one or two who said they've had a go since I've been posting - so I'm sure you have. Whilst many have successfully made small capacity engines as a first go personally I think it's expecting too much especially with a diesel as those piston/liner tolerances are so tight the smaller you get. I've rebored .8cc but not made an engine of that size yet. 5cc is (for me) such a nice handleble size - parts not so big as to warrant a big outlay and not too small for workholding purposes. The 2.5 currently being worked on seems very small by comparison.
With regard to compression - the actual compression is really dependant on the load - for optimum revs it will vary depending on propellor diameter/pitch. They can also be ran with the compression backed off to lower the revs - engines used for sport and scale free flight models traditionally run them in this fashion.
Once well run in some engines do require a slight increase in compression to start, others not - it is quite difficult to describe as it's very much a feel thing. The smaller they get the more difficult it can be - some engines like to be very wet, almost flooded in fact, to start while others will get going on a couple of finger chokes
On a good performing engine the compression is rarely touched bar a tweak or so - rather with well established settings the needle is opened a turn more and the engine flicked and allowed to warm in bursts - it will start and run for a few seconds - and this is continued each burst running a bit longer then finally the engine will break into intermittent, burping, firing before settling down as the needle is gradually turned in to it's normal setting. The compression may need to be slightly adjusted depending on conditions - ambient temperature for instance. The Rivers 3.5 Silver Arrow I once had virtually never required the compression adjusting over several years of flying - a lovely motor to use.
Watching the video possibly appears to give a contradictory view - but this is first running and finding where the settings are. It's easy to flood an engine when you don't know it's characteristics and the the comp then does need backing off - that's the good thing about hand starting - you can rapidly feel that situation develop. Once running if the engine goes' hard' and begins to die it's over compressed - quickly backing off will ease things but if the engine has got hot it will usually come to a stop in a very laboured manor.
If anyone in the UK would like to see small diesel engines being operated to their very top degree then a visit to the control line team race circles at the Model Aircraft Championships at Barkston Heath near Grantham and held over the August Bank Holiday is a must - an ideal time and place to stock up on diesel fuel too ;)
Hope that helps a little Nick
Regards - Ramon
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Hi 'Guys',
Just a short(?) update on whats been happening over the last couple of weeks and one which will bring this particular engine project to a close.
Along with finishing the said article on the Mk1and 2 for the ME mag which has now been sent off I've been making parts for a 'Stockton and Jehlik' version of the 15d only this one is correct size - 2.5cc. All the details of this highly modified engine were published in a 1967 Aeromodeller magazine however unlike all the other 5cc versions made so far including an S&J this one is destined to be used as intended and is to be fitted to a replica of S&J's team race model 'Jefe'.
As per the original (modified engine) it utilises some 15d parts, namely the crankcase and piston and liner however though the original also used a standard but slightly modified crankshaft this one had a new one made to suit the prop driver/spinner arrangement.
It's now finished so for those with an interest here are a few pics and captions...
The front bearing housing and backplate. These were machined from a higher spec aluminium (Alumec 89) than the usual 6082
mainly for the fact that the rear valve bearing has no sleeve - how well it stands up remains to be seen.
(https://lh4.googleusercontent.com/-YUTuYPPc3GE/UcLhXpJ_6YI/AAAAAAAAH4k/5lTPtrD8Pd4/s640/DSCF3238.JPG)
The induction system differs from the original rotor disc to that of a rotary valve which is still driven by the crankpin extension.
(https://lh3.googleusercontent.com/-2DFDM7j-4KY/UcLhlJMIXMI/AAAAAAAAH5M/PnJ8Srw8FAM/s640/DSCF3252.JPG)
The original crank case. Unfortunately the front and rear faces were well out of parallel by some 0.2mm so after machining the as cast mounting lugs (a considerable fault with the original) true to the exhaust register the case was carefully set up, a very fine cut taken through the bore and all faces brought square and parallel
It had also had the cylinder bolt holes opened to 5BA, one of which was drunken and all slightly out of line to the bore. After setting up to the register for the exhaust flange the holes were opened up to 4BA and threaded ali inserts screwed in with JB Weld. After 24 hours these were re drilled and tapped 6BA - a successful reclamation.
(https://lh5.googleusercontent.com/-LVXHjiHFIIQ/UcLhqrewF6I/AAAAAAAAH5c/Gjt4B6_p68I/s640/DSCF3257.JPG)
This one is for Per ;) - it is the composite contra piston - the outer flange is a tight press fit to the liner and the inner moving part - 8.9mm dia - a tight but moveable fit within it
(https://lh3.googleusercontent.com/-_uRTCfevW9s/UcLhwOtE5HI/AAAAAAAAH5s/7WOA7rps0Xo/s640/DSCF3268.JPG)
The original article called for a (relatively) large diameter cylinder head with fins of 25 thou thickness and a 25 thou gap cut "with a tool ground from a hacksaw blade". A tool holder was milled up which worked extremely well but unfortunately an attempt to grind side relief into the blade led to the blade disappearing on the first cut. Thereafter the tool had no relief but the rubbing caused pick up which pushed the fins over - as called for they are quite deep 7.9mm. After 'not a little anxiety' as each fin was achieved - the fourth but last is hanging on by such a small amount it can be deflected quite easily - it did not take much to decide that it should go in the bin. Not only that but cleaning the swarf from the fins proved a real a pain and quickly lead to the realisation that as such, despite the extra surface area, any build up of detritus would soon lead to ineffective cooling anyway.
(https://lh3.googleusercontent.com/-qyIeD-xXAXY/UcLhdXgry2I/AAAAAAAAH40/SKpd8EqvruE/s640/DSCF3243.JPG)
A decision was made to do the same as the 5cc version and reduce the number of fins and open the gap. These were cut using a cutter ground from a discarded FC3 cutter shank which allowed some side relief and the whole thing was so much easier.
Incidentally - the bolt holes are put in first - this makes deburring the holes much much easier and is much less likely for the drill to wander when going through separate fins
(https://lh3.googleusercontent.com/-5C8CLfnx1uI/UcLhf5-l8JI/AAAAAAAAH48/zP7uYViCHKc/s640/DSCF3245.JPG)
I think you'll probably agree it was the right thing to do
(https://lh6.googleusercontent.com/-T0b7sTzXoUY/UcLhajDB3uI/AAAAAAAAH4s/nZbjiBc5Mg0/s640/DSCF3239.JPG)
The crankshaft was turned from En24T but this time (for a first time too) the crankpin was cut from a hardened steel pin and pressed into the web with about .0125mm interference. Again time will tell how this works out
(https://lh5.googleusercontent.com/--9j3QZERgI4/UcLhim-AVtI/AAAAAAAAH5E/4mVzXaFnqD8/s640/DSCF3248.JPG)
The Prop Driver, Sleeve Nut and Spinner parts. The brass spinner-nose screws into the front of the sleeve nut
(https://lh3.googleusercontent.com/-3lO_xLfMtfE/UcLhn9YR41I/AAAAAAAAH5U/KDYsBkq4XQ8/s640/DSCF3255.JPG)
The original used the nylon front end of a Cox TD-049 and its venturi/spray bar system. The intake parts here are original Cox but the case is machined from hard plastic.
(https://lh5.googleusercontent.com/-x4kel5xTehk/UcNordcMVVI/AAAAAAAAH6c/4uyWNLvZojk/s640/DSCF3282.JPG)
(https://lh5.googleusercontent.com/-Aq8rRhui6MI/UcNoufjksoI/AAAAAAAAH6k/SmN8QCNafXs/s640/DSCF3291.JPG)
All parts were given a thorough cleaning .....
(https://lh3.googleusercontent.com/-NnVUtmlTsBo/UcLhVAWkqYI/AAAAAAAAH4c/ZMIxBIdI4gU/s640/DSCF3228.JPG)
.....and it was finally assembled today. The backdrop is a copy of the original 'Aeromodeller' article
(https://lh5.googleusercontent.com/-hhfGzW22Ous/UcLhyk7cjEI/AAAAAAAAH50/Tzge1e_3aZQ/s640/DSCF3271.JPG)
and this is it with it's big brother
(https://lh6.googleusercontent.com/-cArCeb3x9Is/UcLh4SXei6I/AAAAAAAAH6E/DDAp8QgLUfc/s640/DSCF3277.JPG)
Well 'Guys' thats the 'Eta' project over :D and for me time to take a break from machining - (Is that okay Eric? ;))
I guess by now you've all worked out that I'm not a true blue, dedicated, dyed in the wool, model engineer like most of you are but someone who likes a bit of a change from time to time. On that note I'm going to change tack (pun definitely intended ;)) for a while and do something completely different as plans are afoot to build a Marblehead yacht.
That does not mean to say I'm not intending to make any more engines - theres a couple of Italian beauties waiting in the wings for starters - but needs must ::)
I would however just like to say a big Thank You to all of you for your kind comments and encouragement throughout this thread - all extremely valued and much appreciated.
On that note then I shall 'slip me cable' for a while and return at some stage refreshed and ready to 'have another go'
Back 'afore too long then - Ramon
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Ramon,
Thank you for the builds you've shared so far.
I, for one, would love to see the yacht when it's finished (if not an occasional progress teaser).
--Tim
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I agree Ramon. Don't be a stranger here. Thanks for all your efforts, and sharing these builds.
Bill
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Thanks Ramon, a really interesting series of articles/threads, love the "brothers"....big and small!
cheers
Bill
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Thanks Ramon!...do keep in touch and send us a few pics of what your got up to!
Dave
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Best wishes with the model boat Tug. As Dave says looking forward to seeing some photo's of it.
Jo
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Ramon you can't really leave it there, you know we will want to see the S&J when its in the airframe and hopefully in action. ;)
Hope you enjoy the summer of sailing and find your way back into the shop soon.
J
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Ramon,
Thanks for all your postings here. :praise2:
Enjoy the sailing. :whoohoo:
AND
Please remember:
The definition of a "Confident Navigator" is the navigator who can tell you the name and exact lat/long of the shoal your currently suck on. :LittleDevil:
Best Regards
Bob
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Great build Log Ramon :ThumbsUp: :praise2:
Look forward to see the write up for the ME Mag
And good luck with your boat build I'm sure she will be cracker.
Stew
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Thanks for the posts Ramon
I presume that Marblehead will be a model one C I hope , In my dim distance past I used to race one made the sheet winch's with proportional feedback ( way before you could by them ) by cannibalising a servo and a mechcarno sp motor that had a variable gearbox
it was an interesting project confused the clubs measurement sec. as I had painted the bumper and they insisted it was over length until i demonstrated the cork number was not part of the hull as per the racing specs ( for those not into sailing length is important )
I seem to remember that the class of Marblehead was to create a model that would fit into the cars of the day
best of luck in your new project please show us the winches if you build them
Stuart
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:NotWorthy: :NotWorthy: Thank you very much Ramon for your fine article and how-to approach on some extremely fine model engines :NotWorthy: :NotWorthy:
Thanks for the info and pictures of the special J&K parts ;)
I'll agree that the thicker fins with more spacing looks right (better and stronger) :)
Enjoy your boat trip and as said - don't be a stranger, we all appreciate your work.
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Ramon it is always a pleasure to read you threads, they are always well constructed and like a class room to learn from. Please return once you have enjoyed your leisure time. I also will be on vacation next week and will be heading for the UK and Italy for two weeks. Enjoy Ramon.
Don
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Ramon, I can only echo what has been said regarding your contributions to this forum. Good luck with the Marblehead, I've just given myself a crash course in them (care of google), I'm sure you'll do a fine job of it. Hope we get to see!
Cheers, Hugh.
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Hi 'Guys' - just caught up with this so as ever thank you for your kind thoughts and good wishes for my coming project.
Obviously it's pleasing to hear you are interested to hear of progress so will pop the odd post on the Chatterbox board as and when.
Re the aircraft Jason - I made the engine as an exercise and a 'thank you' for someone who helped me early on. He's going to make the aircraft and hopefully race it in the relevant events ('Classic' Team Race I think)
I'll pop in from time to time but I do tend to get a bit focussed ::) so forgive me any long lapses.
One last thing - a bit early but just in case I forget/miss the opportunity.....
Jo - Good luck with your big day at the Guildford Rally. You've certainly prepared for it well so I hope it goes as well for you as it can and that there's lots of interest to reward those efforts. Have a really great time. :ThumbsUp:
Regards to you all - Ramon
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Jo - Good luck with your big day at the Guildford Rally. You've certainly prepared for it well so I hope it goes as well for you as it can and that there's lots of interest to reward those efforts. Have a really great time. :ThumbsUp:
Regards to you all - Ramon
Thanks Tug: I am looking forward to the 22nd July ;D
Jo
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Hi Guys -
You may recall that at the start of this thread I said I'd been asked to write an article on the build of these engines.
I thought someone might like to know that it's recently been confirmed that it is due for publication in the Model Engineer from issue 4473 which I think will be the late January issue.
Apparently a short intro in that edition will followed by the start on the build proper in the next but one - possibly even a cover pic too :o.
It's been a while in coming but 'all things come to ....' springs to mind
Regards - Ramon
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Congratulations on the publication being announced Ramon. It should make a nice cover picture too!!
Bill
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Congrats Ramon, it is well deserved. I look forward to some great reading.
Don
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:ThumbsUp:
It will be nice for the readers of ME to see a few real model engines being built in their magazine for a change :LittleDevil:
Jo
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When I spoke with Diane at Sandown she said she was half way through proof reading so I thought it would not be long, Look forward to reading it again.
There will also be a large version of the Mastiff to come later in the year and possibly a variation on the Nemett Bobcat/Jaguar.
J
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Hi Ramon,
Congratulations, is it the same engine that has been shown on the modelengineeringwebsite? I looked at some of those set-ups before I looked at the authors name, it had Ramon stamped all over it and I was right.
If it is the same engine I shall have to look out for the ME magazine at the local newsagents,
My best regards
Gray
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'Morning 'Guys',
That's very pleasing to hear you're pleased too so I hope it lives up to your expectations.
When David Clarke (yes it goes back that far) asked me to do it I was concerned that it might seem repetitive following the one on the 'Racer's so we agreed that it might be better to cover it in more depth. Diane agreed when she took over that that should remain so that's hopefully what has been achieved. That said it's more or less the same ground as covered on here on other builds - you can only say so much about making these fascinating little devils.
Gray - how are you doing ? enjoying your retirement I hope :ThumbsUp: -
No the engines on the 'modelengineeringwebsite'are the Super Tigres that were detailed on the - er, ahemm! - HMEM web site.
David Carpenter has been asking me to do something for his site for some time but it's never been the right moment. Recently he asked if he could use the Tigre detail from HMEM and rework it slightly himself. I was expecting him to present it as a 'one off' article and was surprised when it appeared as a build article especially right on top of this one coming out in ME - that's why he's agreed to put it on hold for the moment.
Thanks as always for your interest
Regards - Ramon
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Congratulations Ramon. Unfortunately I am only subscribed to the MEW.
Vince
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Hi Ramon,
I am not doing too badly, how are you and Sue? Retirement is hectic I do wonder now how I ever went to work.
I did wonder why the article had stopped suddenly but all has becomes clear.
I shall still look out for your work in ME, I enjoyed your Anodising article a bit back in MEW, it is in my file for future reference.
My best regards
Gray,
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What a fascinating read. Thanks for the patience and documenting your engine build. For piston fits, if you incline the compound slide to 0.5 deg angle, every 0.1 mm is 1 micron per side movement. If you move 0.05mm it will be 0.001mm on diameter movement. This is assuming that the sadle moves exactly as it should. To aide in this, I added a continuous oiling pot that keeps the saddle/bed wet with slide way oil. It works very well for fitting F2C diesel pistons without lapping.
Neil
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Hi Neil and welcome to the forum. When you have a minute, please post an introduction in the " introduce yourself" section so that you can be welcomed by all
Bill
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Bill, apologies for this old post being resurrected - it came as a surprise to me too but it was partly my fault.
I've been engaged in conversation on another (model aircraft) forum over the timing aspects of a potential new 5cc diesel. Neil had PM'd to ask if I had covered previous builds and I sent him the link to this one.
Though I hope he will, as he obviously has a lot to offer I can't say if he will continue to participate. My thanks to Neil however for taking the time to register to be able to post and for his comments.
I'm interested in what he is saying regarding piston machining/finishing and will raise this again in what I hope will be a new build in coming days.
Regards - Tug
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apologies for this old post being resurrected
No need to excuse Ramon - it is a great thread and it will stay that way as long as this site exists (along with many other threads here).
I knew about the use of the compound slide for those extremely fine increments, but would not have thought that it could be used for a cylinder in a CI engine ….
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Thanks Per :ThumbsUp:
Yes I've been aware of the technique for many a year but it does raise some interesting questions for me in this specific application. I'm intending to start a new engine quite soon so will comment on this at the time - hopefully with Neil's input.
Regards - Tug
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I was also going to raise a question or three for Nick about it, but will wait for your new thread which I'm looking forward to.
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Hi Jason - Looks like we don't need to wait now :D
I have just finished a new set of drawings so hope to start at the end of the month ;)
Regards - Tug
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Great news :whoohoo: a new CI engine from Ramon :pinkelephant:
:popcorn:
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Great news :whoohoo: a new CI engine from Ramon :pinkelephant:
:popcorn:
I think he may be carving his new IC engine from Aluminium not CI ;)
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:D
Easily done Jason - I've just done the same elsewhere ::)
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CI-Compression Ignition 8)
I can't wait
Rod