Gas Engine Powered Shop Rags. History and Demo.

Flying shop rags were popular after we broke our planes as kids. We were addicted to these Cox glow engines, so we had to run them, just to run them! Today, I run the smallest of the Cox engines (.010) and show how to make flying shop rags. In those days, we usually ran and tried to catch them as they landed.
The Tee Dee series, without a doubt, is Cox's greatest and most famous engine. This engine was "THE" engine to use in competition for many years. It was designed by Bill Atwood who had been hired by Cox specifically to produce the Tee Dee line of competition engines. The important features of the Tee Dee are as follows:
· Tapered cylinder and a lightened and tapered piston
o Result: tighter piston fit at TDC and less piston mass = more performance.
· Two deep bypass ports with two bypass booster grooves on each bypass port, extending slightly above the main bypass groove
o Result: significantly better air fuel mixture induction = more performance
· True peripheral venturi
o Result: more efficient fuel intake, fuel draw and induction = more performance
· Precision balanced and milled crankshaft
o Result: better fuel intake, better balanced engine = more performance
The Tee Dee was tested by Aeromodeller Magazine in 1962 and the output power was recorded to 27,500 RPM. In 1973 the bypass porting, crank shaft timing and venturi were modified slightly and a mesh screen was added to the venturi to keep out dirt. This resulted in a minor performance improvement over the earlier versions.
Cox engines were in production for more than 50 years between 1945 and 2006 by L.M. Cox Manufacturing Co. Inc. who later became "Cox Hobbies Inc." and then "Cox Products" before being sold to Estes Industries when it became Cox Models.
Hobbico purchased Cox Models in January 2010.
Thank you for watching another of my History lessons and all the support.
Dave Herbert
AMA 8221
Leader Member
Contest Director
Scientific.