Would standard Borosilicate tube do?

**LINK**

I've bought from this bunch before- send a message and they can create pretty much whatever you need with nicely ground ends I believe.

If you can't get the glass tube, its still possible to do the build by using stainless steel, you can make the cup shape by welding an end on a bit of tube, job for a TIG welder, or you can carve it out of solid bar, takes time, but well worth it. Both the hot cap and the displacer can be made the same way.

One of my motors, built from junk found in the workshop. Power cylinder 3/8" bore x 12" stroke. The hot cap is made from the steel case from a dead AA size Nicad battery.

Ian S C

Yes the Borosilicate tube will work, that's what Pyrex is.

Here's the hot end of the little motor above, the hot cap is lying in front, behind that on the left is an AA size Alkaline cell casing(+ tit on wrong end), next is a Nicad battery case, the next two are an AA, and a AAA battery. I'v got a pile of old AA Nicads from old LED garden lights.

Ian S C