As you can see from the picture, the Ridders “bobber” is quite a pretty engine.
If it works perfectly it develops just enough power to revolve, but not enough to do any work or to overcome any perceptible internal friction.
Unfortunately, my Ridders does not even turn over with the heat applied. It revolves freely by hand, so I do not see where the problem is. In any case, now that I know how powerless these machines are, I have lost interest in spending more time on it, and I am returning to paint and finish the beam engine.
The pictures are for interest only.

(ps.  Note made April 2017.   About a year after I originally posted this, I returned to the Bobber.  I made a new piston from graphite, replaced the 3 steel balls with ceramic balls and retried it.   It still did not work.  Then I tried varying the number of ceramic balls.   With 2 balls, it ran perfectly!   Smooth and fast.  There is a video of the feat in a later post.)

This is the first engine which I have made which does not function.

Almost fully machined Ridder “bobber” heat engine.
With heat applied.
Unfortunately it does not work.