Wooden muffler

The Mark's Models Bushwhacker had a plywood muffler and it was very quiet for the day (this was back in the 70's and 80's.) You epoxied aluminum foil to the inside of the wood pieces and then epoxied the whole thing together and then glassed the outside.

I had 3 of these planes over the years (and still have one NIB :-) and on each one of them, the muffler only lasted about 10-15 flights before the exhaust pulses blew out the hunk of ply opposite the engine exhaust outlet. Even when using heavier glass on subsequent mufflers (using what I learned with the others) I would always get a blowout. This was using an OS .20 engine.

It's a great idea and really fairs the muffler into the side of the plane which made for a very sleek little sport plane...to bad the construction just isn't robust enough IMHO.

Don

Seems like RCM had something about this in the early 70's.

Actually I found this article in going through my magazine back issues. I even found a Vol. 1 No. 1 RC Modeler from 1963! Anyway the wood muffler article was in RCM June 1974, written by Rod and Mark Smith (of Marks Models). It is billed as experimental, could probably be improved with a modern hi-temp epoxy. Earle

I have an old Bushwacker which uses a wooden muffler. It used plywood, balsa, expoxy, and aluminum foil, IIRC. The mufler was made so that it blended into the form of the fuselage. It made it look really sweet.

Greg