Author Topic: Tug's Corliss Tandem Compound Project  (Read 1299 times)

Offline Ramon

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Re: Tug's Corliss Tandem Compound Project
« Reply #15 on: December 07, 2017, 10:06:05 AM »
Good morning guys - really nice to hear from all of you.

Thanks for your welcoming words and comments which are much appreciated. I will perhaps succumb to your charms and put a bit more up than intended but have to say the time factor is still an important one for me. We shall see what the days ahead will bring.

To comment on a few points :

Crueby - the flywheel does get used but not quite in that form - more on that later

Jason - yes as said it was originally bought as a Twin tandem - I had to go to the Post Office to collect it as they wouldn't deliver it  :o I have to admit I had not even considered the weight factor until that moment ::). We bought a new sideboard for the hall that was intended for the Wide a Wake but having placed it on there decided we didn't like it. The space is therefore reserved for this one ;)
I guess the air pump is bronze due to the amount of water running through it (if used correctly) both the cooling water and the effluent. It's not a particularly nice casting as it's slightly misaligned but I guess some careful fettling will bring it to shape. One things for sure its going to be a real pig to set up for the initial ops on the bores

Bill - the base is 44 inches long by 16 wide so yes another big footprint

DT - I was speaking to Bob Potter just recently - it's all still available  ;) Could make for some heavy hand luggage next time you come  :D

Vince - good to see you here - I do hope this will help give you some inspiration to continue on your engine.

Phil - I'm not sure quite what to do at the moment. The top is a very nicely textured stone like surface Formica layer. I was considering engraving  lines to represent large stone flags but changed my mind at the last minute in case I got it wrong  :-\ My original thought was to try to make this as close to a full size in detail as possible but have stepped back from that ideal somewhat. I think I'll go for a 'stylised' base with simple foundation and concentrate on the engine.

Don, good to see you here too - hope you are well my friend :ThumbsUp:

'Whiskey' - I knew it, you are a silver tongued owd devil   :)

Guys, my thanks to all of you for your words -, Simon, Jim, Bertie, Achim and Kim it's nice to see all your names up here too. I'll try to live up to expectation in coming days and post some more pics later but for now the crankshaft and bearings await attention  - I'm off to the workshop ;)

Regards for now - Tug
"I ain't here for the long time but I am here for a good time"
(a very apt phrase - thanks to a well meaning MEM friend)

Offline jeff l

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Re: Tug's Corliss Tandem Compound Project
« Reply #16 on: December 07, 2017, 01:59:37 PM »
Tug , Thanks for posting this build .Jeff

Offline Tennessee Whiskey

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Re: Tug's Corliss Tandem Compound Project
« Reply #17 on: December 07, 2017, 07:18:09 PM »
So you mean to tell us that Sue allows your models to be used as “objects de art” in her household? Now that’s as good as finding a spouse that owns a fishing boat and a liquor store  :lolb: :lolb:

Cletus

Offline Dave Otto

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Re: Tug's Corliss Tandem Compound Project
« Reply #18 on: December 08, 2017, 12:40:38 AM »
Hi Tug

Thanks for deciding to post pictures of of your new, or new again Corliss project; I have always enjoyed being able to see your beautiful work.
Any progress pictures that you decide to post will be most appreciated.

Dave

Offline Mcgyver

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Re: Tug's Corliss Tandem Compound Project
« Reply #19 on: December 08, 2017, 12:39:56 PM »
That is a great looking project, i'm glad you are taking the time to post the build's progress

Offline Jo

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Re: Tug's Corliss Tandem Compound Project
« Reply #20 on: December 08, 2017, 05:08:44 PM »
Sorry for arriving late  :-[

Is that an all Corliss or one of Peter's Corliss HP and Sliding valve LP engine  :noidea:

It makes a long old engine the tandem but at least it is not as wide (and not as heavy ) as my cross compound  :paranoia:

jo
Usus est optimum magister

Offline Ramon

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Re: Tug's Corliss Tandem Compound Project
« Reply #21 on: December 10, 2017, 03:02:29 PM »
Hi Guys

Jeff, Dave and Mcgyver - Thanks for your interest in this – Jo thanks for looking in too

A couple of apologies –

Firstly - 10K Pete - sorry, I trust I didn't offend by leaving you out – you just ‘slipped the net’ .

I am well into this build at the moment and have not taken many pics of the early stages so can't do much about that. However, despite your very heartening comments to do so I don’t think I can give the time to this that you may like but I hear your encouragement and will do the best I can so will try to remember to take more pics than perhaps originally intended.

Ok - where to carry on.

I guess first off some words on my thoughts on this engine and where I’m hoping to go with it.

The engine was originally designed by Arnold Throp for Terry Fleet of Fleet Engineering Services who offered castings for varying versions for sale.

It was not a scale model of an original prototype but Arnold had designed it on basic engine principles learnt as an apprentice and subsequent engine fitter in one of the last firms of engine makers, Cole, Marley and Marchant. He produced his own patterns for a single cylinder condensing version that was described in the August and September 1982 issues of Model Engineer

Unfortunately Terry lost all his patterns and castings when the foundry he used shut overnight and the design was fundamentally lost to the ME world.

Several years later during a conversation with Peter Southworth this design cropped up. He told me he had Arnold’s original patterns for the left side engine and also a full set of drawings. He had bought them at the sale of Arnolds estate but had no intention of selling them commercially.  The conversation developed much further and the upshot was that Peter kindly made patterns for the other side engine and the castings then became commercially available again.

A full set of drawings had been sent and as said previously the Twin Tandem was chosen but eventually discarded due to the weight factor more than anything else. I originally intended to make this as a Corliss valve HP cylinder with a slide valve LP but having seen Terry Fleets (double Corliss) Cross Compound running at the Lowmex shows the decision was finally made to make this all Corliss.

There are one or two points of the design that I did not like personally – that’s not to say there’s anything wrong with it – just personal preferences. One was the heavy bolting flange between the main bed-plate and the cross-slide bed-plate. I also felt that aesthetically the con-rod appeared a tad short . I did not like the style of LP slide valve cylinder either so decided I would make one to my own vision from solid. Fortunately there was a large off cut from a job at work that was scrounged – ever the inveterate scrounger!

Original intentions were to try to make this as scale like as possible using full size practice where ever possible but again, time and the desire to do so much with 'what's left' has tempered those thoughts to some degree.


As said all the castings proved easy to machine - beautiful homogeneous cast iron. Despite the long storage under the bench however the cylinder bed plate proved somewhat surprising.

The cylinder bed plate or plinth was machined as the other parts ....


...but with the change in in converting to all Corliss came the need to modify the bed plate by machining it's thickness down at one end. This surprisingly led to a degree of warping which would require this op doing again.


With every thing nice and flat at this stage however it was time to turn to actual machining.



Another factor I found a tad lacking was the low overall height of the bed-plates so it was decided to mill away the beading around the castings and mount them all onto an Ali sub plate. The cast in foundation bolt pads were also milled off and would be re-sited further outwards with pads JB Welded in.

The castings were set up at a 2 degree angle - setting each edge level with a scribing block



The new mill played a good part in all this machining but the old Linley, so faithful for so long played it's part as usual



The bolting flange was milled away on both bed plates...



... and everything was ready for the next stage.



Two pockets were milled into the Cross-slide bed and holes drilled through to match two tapped holes in the Main bed plate. These were pulled together with a spacer between (to help lengthen the con-rod appearance) and would be back filled with JB Weld. The cylinder plinth was machined for the HP cylinder at this stage too...



... and this is where it had to be re-faced to reclaim the flatness. Note the blob of blue tack - that helped take care of the resonance and chatter set up by the marginal clamping surface. That extension insert BTW was required to take care of the HP Corliss cylinder footprint.



Another area I decided to change was the cross head. The original had a slipper sliding on the bed direct but a decision was made to fit a locomotive type with two bars. This required the cross-head area to be milled away. The two slots for the joining bolts can be seen better in this shot.


I think that'l do for this time - more later.

Oh yes - 'Whiskey',  Sue has put up with a lot over the years in her own inimitable tolerance for my doubtful modelling and non modelling meanderings. We even once had climbing wall blocks screwed to the hall wall   :o - yep you wanna believe it  ::) but now the tolerance is tempered somewhat. The Waller engine is reluctantly accepted in the lounge and there's a nice Edwardian Yacht in a case in the bedroom - where else you might ask (case of needs must I'm afraid) but that's it - nothing else but I'm working on the sideboard area ;)

Regards Guys - I'm off to do a bit more - 'Ole' Tug
"I ain't here for the long time but I am here for a good time"
(a very apt phrase - thanks to a well meaning MEM friend)

Offline Ramon

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Re: Tug's Corliss Tandem Compound Project
« Reply #22 on: December 12, 2017, 02:12:34 PM »
A few more pics to work toward where matters currently stand.

The two main bed plates were to be set on an aluminium subplate as one piece and the cylinder plinth on another piece. The subplate would replace and reproduce the beading previously milled away. Ali tooling plate is very flat and proved ideal for this.

The two main bed parts were temporarily bolted to the ali plate and once more set up a 2 degree angle and milled to profile standing approx 2mm proud from the casting edges. The vertical edges (in the image) were milled square on the mill axis then dealt with a file to create the angle. The bolt pads have been removed and  the new locations drilled for the new inserts.



At last something could be done toward what had been an idea...
The slots for the cross-head slide supports have been milled and drilled.


Finally it's together, bolted and JB Welded to the sub plate with the cross head supports firmly in place.


The cylinder plinth was treated in the same manner


It was then a matter of settling down with some files and emery to fair all the JB weld fillets and the bolt pads. Once done the two parts were brought together. At first as the joining bolts were brought up tight the end lifted about 2-3 thou so I took a fine file to the lower edges of the ali plate only to increase it to 10 thou ::) Both parts were reset on the mill and the faces barely tickled with a very sharp cutter. The result was better than hoped for - zero movement at both ends and at the bolting face - I really was pleased with that  :) (Says something about my old Linley mill too ;))




I think it's best to keep the posts short but frequent until we catch up so hope you can live with that  :) - as you can see in the background the cylinders were well under way at the stage described so perhaps something on them next.


It's bitterly cold here today, the car still solid with hard ice but the workshops warm so I'm off to finish the eccentrics  ;)

Regards for now - Tug
"I ain't here for the long time but I am here for a good time"
(a very apt phrase - thanks to a well meaning MEM friend)

Online b.lindsey

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Re: Tug's Corliss Tandem Compound Project
« Reply #23 on: December 12, 2017, 02:44:08 PM »
Geeze....that is a lot of progress Tug. Please keep the pictures coming as time permits, this is quite a build!!

Bill

Offline Ramon

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Re: Tug's Corliss Tandem Compound Project
« Reply #24 on: December 12, 2017, 02:48:45 PM »
Yes all done in the last couple of days Bill  :lolb:

No, not really  ::)  I began in earnest on Aug 28th this year so this is catching up. What has surprised me though is just how much I'm enjoying the machining and just how much has been done so far. Novelty's gotta wear off soon though don't ya think ;D

Yes, I'll keep it going now ;)

Tug
"I ain't here for the long time but I am here for a good time"
(a very apt phrase - thanks to a well meaning MEM friend)

Offline Jasonb

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Re: Tug's Corliss Tandem Compound Project
« Reply #25 on: December 12, 2017, 02:57:55 PM »
Thanks for the updates Ramon, nice to see some minor mods that will make it your own.

Online b.lindsey

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Re: Tug's Corliss Tandem Compound Project
« Reply #26 on: December 12, 2017, 03:54:01 PM »
New and interesting projects like this one Tug, keep the novelty alive and well. We all need to take breaks at times but the lure of model engines of all types keeps calling us back eventually :)

Bill

Offline Ramon

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Re: Tug's Corliss Tandem Compound Project
« Reply #27 on: December 13, 2017, 11:51:50 AM »
Thanks Bill and Jason,

Yes the idea was to make it a bit individual Jason, I'm told by Terry Fleet that no one has done the Tandem all Corliss before but somehow I don't think that can be right - surely someone has by now
I've taken another look at that air pump casting and the more I look the more I'm convinced to fabricate one. It's not that bad but I don't think it will look too symmetrical at the ends once machined - we'll see.

Lure is right Bill but I never thought this would ever see the light of day - just goes to show I guess - never part with anything  ;)

Best - Tug
"I ain't here for the long time but I am here for a good time"
(a very apt phrase - thanks to a well meaning MEM friend)

Offline Ramon

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Re: Tug's Corliss Tandem Compound Project
« Reply #28 on: December 15, 2017, 04:25:57 PM »
Further tales from Ole Tugs workshop

A bit more for you  :)

The cylinder castings proved quite an easy machining task. The HP cylinder was as provided by Peter Southworth. One foot was cut off as this cylinder abuts the cross head bed-plate along with the two protrusions on each side. These were intended for reinforcing bars between cylinders but it was felt that they would not have been on an engine of the size that this model would depict.

With the top surface filed much like the bedplates the lower face was machined leaving plenty on, reversing to machine the top and finally as here turning over to machine the datum face still leaving a few thou to clean up after the bore was in. There was plenty of machining allowance as witnessed by the scribed line.




Both cylinders were done like this but the LP Cylinder was machined from a block of continuous cast bar. As said previously the intention was to use this to create a slide valve cylinder and the bore had been roughed in whilst still at work in ’98. The decision to change to an all Corliss engine meant this hole was out of line to the base. To cure this the lower face of this block had a 8mm deep groove cut through the length of the block leaving 5mm wide sides. A slab of cast was machined to suit and JB Welded in to increase the height and once cured the block machined to size all over leaving the feet at each end. The small gussets on each foot were cut from cast and JB’d into slots milled in at a later stage


Both cylinders were bored between centres on the lathe packing up on parallels and shims to get the bores a few thou higher height-wise and dead on centre width-wise.




Once the bores were finished, the lower ‘datum’ faces could then be tweaked the last few thou but this time to the bore to ensure both bores were dead in line with the lower face and at the correct height on each cylinder to accommodate the two differing heights on the plinth. How true wouldn’t be really known until the end covers were in place and the piston rod fitted




Machining the remainder was basically straightforward, the valve bores being drilled and reamed with the blocks set against an angle plate to ensure squareness. The steam cavities proved an opportunity to try out the new mill with a big (for this w’shop) cutter which it handled with ease. It may be Chinese but it did, and has done, all I’ve asked of it so far both with power and accuracy.




I bought this 1/2" radius corner cutter a long time ago for just a pound! Specifically with this op in mind – money well spent  :)




There were lots of 5, 7 and 8BA holes to tap and these were all done by hand by supporting the tap lightly in the drill chuck or in a brass sleeve held in the chuck. As described on another thread on here the drive to the tap was by accomplished by grinding a small flat on the side of the shank for the wrench to grip on. As the end got closer the anxiety levels increased a tad – only a tad mind ;) dreading a broken tap but all 200 plus holes in each block were finally done without mishap.




The inlet ways from the steam chest had been milled in using a Woodruffe cutter but the steam ways into the cylinder required a precise slot using a cutter of the correct width. A simple slotting cutter was milled from Arne tool steel (equivalent to GFS) and the tips backed off by filing. Heat treated, quenched in oil but not tempered and the tips touched with a diamond file it sailed through all four places in each cylinder without a hitch. The cutter was set to each position by touching it on a round bar protruding from each bore then moving back over the main bore and lowering to the set depth






The sides of the cylinders were relieved, not for any specific reason other than it seemed right. The cylinders will be lagged so this wont actually be visible. It was only at the last minute doing this that I realised something wasn't quite right on the LP cylinder. I had made a note on the drawings that the C/L of the lower two holes for the valve lever pivot was on the C/L of the bore. Misreading my own notes ::) I had placed the C/L of the four holes on the bore C/L ::) ::) (age thing - has to be  :facepalm2:) It was easily rectified by milling out a 2mm deep cavity, JB Welding a slab of cast iron in and re-machining and drilling the holes in the correct place once cured.




With all these ops out of the way work could begin on the end covers and glands and finally fitting that piston rod to see how it all aligns but that's for another day.

This is taking up too much workshop time  - I'm off to the comfort zone

Regards to all who look in - Tug



« Last Edit: December 15, 2017, 04:32:02 PM by Ramon »
"I ain't here for the long time but I am here for a good time"
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Online sco

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Re: Tug's Corliss Tandem Compound Project
« Reply #29 on: December 15, 2017, 04:51:28 PM »
That corner radius cutter was definitely a good buy as it's made a nice feature on the cylinder blocks Ramon.  Thank goodness for JB Weld though  ;D

Enjoying following along,

Simon.
Ars longa, vita brevis.