Walking beam engine power cylinder placement

[PKM]

Hi all,

I'm planning a simple tin can engine for my first build, and for aesthetic and practical reasons I'm aiming for a walking-beam engine similar to the Boydhouse design. My problem is that I'm not convinced the epoxy I have for sealing the engine will take high temperatures well- the figure I find most often is 65C, which is about 150F.

I notice that in most builds of this type the power cylinder is placed midway up the displacer cylinder between the water jacket and the "firebox", presumably for simplicity. My question is, are there any good reasons I shouldn't have the power cylinder coming out of the top part of the engine, where the water jacket will help keep the join cool?

If my image embed has worked, there should be a diagram attached to this post.

[jimlarsen]

It looks like an idea that should work. JB Weld Epoxy can withstand high temperature. You might consider getting some if that is how you plan to make the joint. If you read through the Boyd plans you will see he has some alternative methods for making that joint that don't involve glue.

[Junkie]

Hey PKM
you should have no problems doing that. My engines all have the displacer epoxied (low temp stuff) on the side with no problems.