Vertical steam engine with Stuart cylinder

[Michael S.]

In another post, I repaired a Stuart 7-cylinder, and now I'm building a new steam engine. The bore and stroke almost match the cylinder of a French blueprint, so it will be a vertical engine.

First, the upper plate is made from brass. The four columns and the crosshead guide are attached to this plate. Drilling and milling were done on the milling machine, and the curves were finally filed.

Michael

[Sanjay F]

Very nice use of the cylinder you restored Michael - looking forward to seeing you build it 

[Michael S.]

The cylinder now has a brass jacket.

The blueprint shows that the two rods for guiding the crosshead are attached at the bottom with a bridge between two columns. But what happens at the top of the brass plate? Slotted holes are provided there, but how should it be attached? Has anyone ever built using this blueprint?

Best regards, Michael

[PaulR]

That looks fantastic 

[Jasonb]

Do you have the two CSK holes on the correct side of the cylinder end cover? Quite common to have CSK screws into threaded holes in the ends of the guide bars.

The slots on the original plate allow you to drop the whole cylinder, cover,guide, crosshead, etc into place

[Michael S.]

Hi Jason, you have to help me. What are CSK screws? Countersunk screws?
It's probably used like that at the bottom end. I can see that in the first image of the computer animation. There you can also see that the guide rod isn't round. A square shape is better. In the blueprint, it's round. I assume it's simply inserted into the plate at the top. I'll do it that way.

Michael

[Michael S.]

The distance between the two rods in the upper area is not the bolt circle diameter of the 6 cylinder head screws.

[Jasonb]

What is the distance between the inside faces of the guide bars? If something like 20mm than two flats machined onto the spigot would allow the bars to be screwed on to that.

[Michael S.]

Thanks Jason for the helpful advice.
I drilled a 3 mm hole in one of the slots (notches). I could insert the rod there with a tenon or file a square hole.
But your last suggestion is good, and I could do it that way. Thanks.

Michael