Bett-Zee Oscillating Engine-
Here's a small oscillating steam engine that's based on plans one of my students found in a magazine (we re-drew them, using simpler dimensions and some minor changes). Built two of these. Both ran OK but didn't like to idle real low. Not a lot of flywheel effect so that may be part of it. Built mostly from mild steel stock. No photos of the "live" engines (students took them home before I got the camera out).