Stuart Triple Expansion Engine

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Thank You Jens,
Have you run your unit on steam, I cant seen to find anyone that has ? I plan to. Thank You for the great information!
Alec Ryals
 
Alec, still not ready to run the triple steam engine due i was not ready with the rest of parts of reversing links. I am still building the steam engine..
 
Well ive been timing the engine Okay now both directions was just hard to do with other cylinders connected and the pumps ! But it takes 60-90 psi to get the engine to start turning that seems kind of high! all the rings,glands etc cause quite a drag. Also was wondering why some folks put valves atop the cylinder heads or are those oil cups and why ?
Any Thoughts
Thank You
Alec Ryals
 
Beautiful work at your triple steam engine.. :)

Take running-in to adapt the parts togheter to a perfect fit who is impossible to make with machinetools. Same i has drag in the steam engine. It is common in the new unused steam engine. Do not save oil under running-in until all parts is adapted to perfect fit. Do not tighten too hard on packing boxes on glands, tight little until it does not leak steam out of the packing box.

"Also was wondering why some folks put valves atop the cylinder heads or are those oil cups and why ?"

It is up to folks to make the steam engine more realistic to prelubricate the steam engine before use.
Use displacment lubricator or mechanical lubricator if you want.

Storing away the Stuart steam engine after use: Run the steam engine with air and lubricate with conserving oil that you can buy in maritime dealers. To prevent rust develops inside the steam engine, lubricate well with conserving oil. :)
 
I'm wondering why Stuart gives such thick wall tubing for these I guess it must be to retain heat ? I hear these engines need large areas for crossover to make all things work correctly ? Also woundering if I should put some heat insulation under the cylinder shrouds ? I forget the proper name for these covers.
Alec Ryals
 
I'm wondering why Stuart gives such thick wall tubing for these I guess it must be to retain heat ? I hear these engines need large areas for crossover to make all things work correctly ? Also woundering if I should put some heat insulation under the cylinder shrouds ? I forget the proper name for these covers.
Alec Ryals

Yes, to preventing the steam is consensating in the cold crossover and expansion of steam will be reduced. Wrap around with thick string and paint around with matt white paint on crossover pipe for better insulation. The area of crossover pipe will allow the steam pass to next cylinder with less resistance.
 
I'm wondering why Stuart gives such thick wall tubing for these I guess it must be to retain heat ? I hear these engines need large areas for crossover to make all things work correctly ? Also woundering if I should put some heat insulation under the cylinder shrouds ? I forget the proper name for these covers.
Alec Ryals
It may be to make it easier to bend without crushing. The wall thickness makes virtually no difference to the U value, which, if there is no insulation, depends almost entirely on the fluid boundary layers at the internal and external surfaces.
 
Well I was able to bend crossover pipes to Stuarts specks by filling the tubes with lead then bend with a tubing bender I made,
Alec Ryals

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I maked the square treads for reversing link shaft. The pitch is 10/1". The hand crank fastened to the pulley for treading the treads without power from lathe motor. Also a sensitive work without distorting the treads on the work piece. :)

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Nice work on the threads they look harder than the double pitch ones! I had to remake the threaded rod as I didnt have enough travel for reversing even though it was made to specks.
 
I selected the square threads to make more realistic steam engine. :)

To make square treads is not difficult..

Rule #1: Make the threaded hole first and next job will be easier to trim the threads with needle file on the threaded bolt.
The top slide on lathe is not in use, carriage only to form square treads.
keep all tools sharp, use pocket diamond grinder in both coarse and fine grade to smooth out cutting surface (both rake and end clearance).
Allways handcranking the spindle when you are working with the small threads to prevent the work is spoiled!

Part #34

1. Drill hole 3,5 mm root diameter
2. Make the threading tool of old drill grinded (i used the old HSCO drill, you can use high speed lathe tool too) to right size 10/1" pitch = 2,54 mm pitch : 2 = 1,27 mm wide and 1,5 mm deep tool and the tool must have place to go into the 3,5 mm hole.
3. Thread up the treads in the hole 0,04 mm each time until the right size in main diameter is 5 mm.
4. The last work: Thread up the threads without change the measure on handwheel on carriage until all swarfs is disappeared due the tool is a bit flexing under work.

Part #55

1. The main diameter 3/16" and root diameter 1/8" showed as in drawning.
2. The threading tool has a wide at 1,29-1,3 mm (1,27 wide is not necessary on the bolt due we need the clearance in threads without jamming)
3. Thread up the treads on the bolt 0,04 mm each time until the tool is touching on root diameter
4. Tread up the work without change the measure on handwheel on carriage until all swarfs is disappeared due flexing bolt.
5. In case the part #34 can not go into the threaded shaft due the threads on the bolt is too wide (if the wide of tool was smaller than 1,27) : Use thinn needle file to trim the wide of the threads and take a test to fit the part #34. You can polish the sides in the threads to make smooth moving the reverse link.

I has Sieg lathe who has 0,04 mm for each mark on the handwheel on carriage. Your lathe can have other size for each mark, find out how much marks you need for each threading.

:)
 
I had to remake the threaded rod as I didnt have enough travel for reversing even though it was made to specks.

My treaded bolt is a bit longer since i can not be sure the lever is in right length due the swing radius can be longer who need longer threaded bolt to make complete travel between forward and reverse.
 
All valves and excenters are adjusted for each cylinders and testet with air for each cylinders. Now the steam engine is running on air pressure. Funny to see the triple steam engine as a freeze machine due the air do not have the properties as steam: Expansion. :)

Next work: Vacuum pump, waterpump. :)

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All valves and excenters are adjusted for each cylinders and testet with air for each cylinders. Now the steam engine is running on air pressure. Funny to see the triple steam engine as a freeze machine due the air do not have the properties as steam: Expansion. :)

Next work: Vacuum pump, waterpump. :)
Cool very nice work
Alec
 
I wounder what type of fitting is intended to fit the flat face an I think its a #5 BA thread on the water pump inlet an outlet.
Alec

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I am making the vacuum pump and drilling the hole for vacuum pump in the soleplate. The problem is the machine tool who the home worker do not have: Big lathe + faceplate or a big milling machine. The solution ---> see the photo what i did. First center is set, then clean drilling with boring tool for be sure the hot spots in cast iron in sole plate is removed and in correct size 3/4". And next drill 3/4" to make 60 degree bottom in the hole for vacuum pump. To prevent the soleplate is rotating: let the soleplate lying on apron with the steelplate between the apron and soleplate for smooth moving. Under work, be sensitive to avoid accident during work. :)

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