V-Twin Wobbler

 

This is my own design after finding that the PM Research model only comes pre-machined.

  

This was quite an interesting project having to create an air routing manifold in the center block to allow direction reversal.  The handle sticking up behind the air inlet controls a rotary valve that allows speed control along with direction of rotation control.  It is the same operation as the PM Research model except that there are no cast parts in mine.  The pistons are .5" dia. with a .75" stroke, double acting.  Everything is milled from rod or flat stock.  It turns at 2300 RPM on 15 PSI of air.