While setting up my hollow log planes for the Walt Musciano event, I had the opportunity to tinker with a bunch of Cub 049s.
The plane shown in the photo is my best attempt at hollow log.
It is the Bullet and, weighing around 5 ounces will do most of the pattern.
The wing is 1/8 thick and the leadouts are INSIDE the wing - figure that one out.
But, to the engine.
1) I removed the cylinder base gasket to raise the compression a bit.
2) Cleaned up the crankshaft, polished all bearing surfaces and smoothed out the intake port.
3) Deburred and polished the connecting rod, added a lube hole at the lower end
4) Deburred and polished all surfaces inside the crankcase.
5) Slightly opened up and polished the cylinder bypass ports.
6) Relieved the lower half of the piston by polishing with crocus cloth - hard to measure but I estimate around .0002. This supposedly will reduce the piston-to-cylinder friction a bit.
7) Cleaned up and polished the inside of the venturi.
Swinging a 5 1/2 4 nylon prop and running on 30% nitro/20% synthetic, it had no problem staying out on the lines, even in the overhead maneuvers.
Bob Z.
Topic: Who does hop up work on Cub .049 engines? (Read 1091 times)
