Fire eater engine book 2

[rolland]

I have been studying the fire eater engine in "Steam & Stirling" book #2 and when working out the cylinder dimensions they don't seem come out right. The flat side if using the existing measurements I come out with a .406 for material that needs to be removed . I got the measurement by counting the 17 fins being 3/32 each and that worked out to 1.59375 leaving the .406 for removal on a 2 inch od cylinder. It just don't look right to me looks like the bore wall will be really thin..
If anyone has built one of these I would appreciate any help/guidance

[Mcgyver]

I made one of those years ago... a fun engine to run. It would be nice if the drawing gave that dimension....it really just wants you to end up with 1" width of the flat. I just measured mine, OD is 2" and I took just over 7/16 of - .440 (more than you were thinking).

oh, small tip.....running is really dependent on the flame's position. I put a rare earth magnet in the base of the fuel tank and a disk of steel recessed into the bottom of the AL base....so its easy to move it about and have it stay in place

[rolland]

Thanks that answers the question, the photo also.

[vpt]

Nice looking engine!

These have always intrigued me. Would probably be the first I would build if I were to start small engines if I make it to retirement (and if I even get to retire).