It would not be too difficult to work out the geometry for this engine.
Start with drawing a piston, find the TDC and BDC points for the piston that alllow a little clearance between the piston and the head.
Convert the piston travel to crank arm length.
If you can't find any drawings, you can send me the following, and I can work out the geometry:
1. The distance from the center of beam to center of one outer boss, and from the center of the beam to one of the intermediate bosses.
2. Final bore dimension.
3. Total bore length.
4. Distance from bottom of A-frame support to centerline of the bearing that sits on top of the support.
5. Dimensions of port face that is on the cylinder, and the diminsions of the ports.
We can create drawings as far as setting up the correct geometry that will work.
If you are good at fabricating steam engine parts, such as piston rods, gland nuts, etc., then you should be able to work it out using the geometry drawings.
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