Phenolic Board? Plywood? Aluminum?

[Dennis Leonhardi]

I acquired a nearly complete profile which is nicely built, but set up for an engine about twice as big as reasonably needed.  Rather than basically redoing the motor mounts/doublers, I'm thinking of attaching a "plate" if you will, cut out for the smaller engine.  We're talking a .10 here ... A friend of mine used to make motor mounts for his RC planes out of phenolic board and they seemed to hold up very well.

Suggestions/comments?

OK, now suppose the engine is a .40 ...

TIA!

Dennis
 

[Geoff Goodworth]

Has the model been used?  If not, a water resistant carpenters' glue will make a stronger joint than the timber around it.

My Ringmaster was built with the bearer spacing at 1 1/4" but I only needed 1 1/8" for an FP/TT 25 so I glued pieces of 1/16 ply to the inside of both bearers and left it a few days before I drilled the engine mounting holes. The nose has survived a wind gust that gave me four pieces instead of one. The breaks were all fairly clean so the repair consisted of removing all the hardware then one at a time, gluing the pieces back together with aliphatic carpenters' glue. That was nine months ago and the model has been flown several timea a month since.