Stew.
I don't intend this to be a resurrection posting. I've precious little time to spend building Gold Blend, as it is!

I might have a rummage round, in a day or two, and take a few orphanage pics. There are still a few left in there....

Dave.
I don't think this piece of 3.5" bore brass ever went bang..... I would expect a case to have a tapered bore, and the little flange is neatly soldered on.

In fact, all the silver soldering and workmanship is first class..... But (I think) the design is wrong, in the detail.......

The short displacer cylinder is much too thick wall brass, and a regenerator displacer wastes too much space in a little engine like this.
My thoughts....... Unless anyone knows different?

David D