Alot of the older kits had wood selected more for its die cutting characteristics than weight or strength. Especially for a 3/8 or 1/2 thick fuse piece, die cutting of soft material causes alot of crushing--so they made it firmer.
Putting silkspan or other fabric over the wood with dope or other material will make the fuse adequately strong. No need to go overboard as the Buster fuse isn't that long.
A long-moment stunter, like a cardinal for instance, needs both a light-weight fuse to keep the CG in the correct plae and it needs to resist flexing to keep the control surfaces in alignment. On stock kits, you can watch the fuse flex from outside the circle. In those cases, glass or carbon cloth with epoxy, a built-up frame fuse planked with 1/64 ply. or some more esoteric fuse construction can be beneficial.
On one of my "full-out-profile" models (the little plane that could), I used a 4 Lb/cuft plank fuse with a carbon tow truss wrapping around the plank. Appears as a series of bridge girders bracing under the silkspan. It is one of the stiffest and lightest fuse structures I have seen.
FWIW
Curt
Topic: hard balsa (Read 1451 times)
