Stuart Triple Expansion Engine

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huntandfish

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I have completed a large % of my Stuart Triple and I am in the assembly stage . I see from earlier posts that there are several members who have built this engine and my question is what is the prefered method of fixing the reversing shaft levers to the shaft ? I cant see anything on the drawings . I could simply lock them on with studlock but what have others done ?
 
I have seen levers pressed onto shafts, and also small allen head setscrews used.

Not sure if either is applicable here.

Pat J
 
I tried a set screw thinking it would be good to retain the option of adjustment , but there wasnt enough grip .
 
A small pin across the shaft....that way I could take it apart if I desired.....but I doubt you will ever need to..

Dave

 
It sounds like you are on the home stretch. I have recently started on the Stuart triple expansion. Despite it being my first metal working project and a very steep learning curve, I have set very high standards. After making the 8 columns, I figured I might as well dive in deep and make the crankshaft, which I just completed yesterday. If the rest of the parts come out so well, I'll be elated.

As for fixing the reversing shift levers (part 32) to the reverse shaft (part 54), i believe Stuart specifies 4 taper pins, which are listed on the parts list directly below the reverse shaft. If you have the Model Engineer magazines, it shows drilling for the pins with a long drill bit after everything is assembled and alignment has been sorted out. IMHO, there should not need to adjust these after the fact. I have seen some poorly built engines fixing them with set screws and bolts, which doesn't look too good, and unless a dimple is machined into the shaft, I would think they would almost certainly slip. Using a press fit might also be a problem for the two shift levers that are in the middle of the long shaft.

Hope this helps, and please post photos as there is much I am learning from each one I see.
 
rhankey
Thank you the taper pins seem the way to go . I hadnt noticed them on the parts list !
Did you fabricate the crank and braze it ?
 
I made the crank from a single piece of 1.5" solid bar stock. I will attach the counter weights as seperate pieces with studs as detailed in the drawings. I haven't decided whether to peen the studs as shown in the drawings or to machine a shoulder to the studs. I'm a little scared of peening the studs and dinging or bending the crankshaft. I'll figure that out once I have made the counter weights.

I had been debating making the crankshaft from 1 3/4" bar stock so I could machine the counter weights with the rest of the crank shaft, but it looked like it would have made life a whole bunch more difficult.
 
rhankey
Saw your crank on the other thread , it looks great I fabricated mine . It works and runs true but not as good looking as yours . I uysed the Stuart casting for the counter weights with studs as the drawings not peened over yet but i will fix them that way . I am currently in initial assembly fettling the pieces I dididnt quite finish or left a little long etc ! It is taking some time .
 
Hello,
I just got my Stuart triple, and a few more goodies in the mail today, great castings from 1959. and started with a file.
Alec Ryals

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Hello Alec

As Bill said that's a really intimidating photo. Are all those parts for just one engine? I think I saw three crankshaft castings.

Vince
 
Yea that's what I said to myself you should of seen it when it was all just a box of lots of parts for several engines and a vacuum pump, Has any one done a triple as I am kind of lost on attaching the high pressure cylinder to the I.C. and the L.C and what is a good machining procedure, any thing will be of great help.
Thank You Very Much.
Alec Ryals
 
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Here is a photo of the castings I got for the triple I'm not sure if there is anything missing and I only have one drawing out of three.
Alec Ryals

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My triple was bought in England back in June 1960 for 13 pounds and 33 -- Wow
Alec Ryals

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Well I found out how to connect the HP to the IP,LP cylinders no angle needed like I thought, Now my next question is should I add the gasket between the cylinders so that all deminishions will fall into place with the .016 gasket material, I think I will bore the cylinder centers and mounting holes with a gasket in place rather that find out later things don't line up. Here in photo I super glued the mounting ears to 1/2 parallels then clamped to the table so all the ears will be even and that alines the casting pretty well on this one. then took little cuts on the top of the cylinders till it cleaned up as this will be my referance leaving .027 per side for my shaper to finish after I add the high pressure cylinder.
Alec Ryals

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Now I'm going to bore the cylinders and face the ends -.010 on the bores and for honing and .004 over on the length for lapping, I'm picking up center scribe lines here.
Alec

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Well I just got threw boring out the cylinders and facing the ends, now I have 61 holes to drill on just this one piece, next it will be drilling the holes that attach the HP cylinder to the LP & IP together then resurface the unit as one and face the remaining end then drill 61 holes plus another 21 holes of which about 3/4 are threaded Opp's did I loose track :) Here is a import C-wrench that would not let go I keep tossing it but it keeps coming back.
Alec

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Amazing work your doing there Alec, don't skimp on the photos please mate, I'm really enjoying this build!

cheers, Ian
 
Thank you Ian,
I really need a new camera were do you live.
cheers
Alec
 

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