A friend had asked me for information/drawings on the Rotary Piston engine model
made by Robert S Hedin , a Simpson and Shipton engine.
Polly Engineering in the UK is offering drawings /kit for the short stroke version, but
He is looking for the original ones by Mr Hedin.
We think it may have been a Modeltec article or maybe even a Popular mechanics from the 1930's /
Julius De Waal has redrawn the engine ( in metric) , but my friend wants the original version
A help or leads appreciated
Rich