As others said, stick and gusset is lighter, but early Avid-Flyer, Kitfox, the Kelly-D and others successfully employed this method... no reason it couldn't be used so long as the bird is engineered for it...Why go through all the time gluing gusetts on rib, would it not be easier to make a jig and use a router...
Key word there Scott. Planes like a Volksplane were designed to be simple and easy to build. You stack up plywood and saw out the ribs on a bandsaw. Compromise on other parameters perhaps but the objective was make them easier to build vs built up ribs.would it not be easier to make a jig and use a router to make them out of say 1/4 plywood
To follow-up... above are a couple pdfs of a modified plywood rib from an Avid-clone (Raven/Mohawk). as you can see the rib is routed out, and then ply cap-strips are glued to finish... pretty light, although not as quick as a simply routed 1/4" might be, but about 60% the weight...Why go through all the time gluing gusetts on rib, would it not be easier to make a jig...
Dana posted this very helpful look at alternative rib construction methods, including foam and ply. Even a bit of testing. Here's the discussion, see the PDF he posted, and go all the way to the end of the PDF. Foam ribs with wood caps were very light and strong, appeared to be approx twice as strong as built-up wood rib of the same weight (and probably a lot faster to build). It was a small sample, but I suppose this is better than a bunch of guessing.An alternative would be to cut the ribs out of extruded foam, and have thin plywood strips as rib caps. Can't think of any right now, but there have been some planes that use this method.
Already been done. Follow the preceding links in this thread.I think the only way to be certain about ply vs stick is to make up a known design rib using both methods, compare weight, then bust 'em. It would be an interesting project at least. Also influential is the type of spar and their location re cord %. Keep the ends rigidly supported (x, y, and z axes).
I would also add that if ply was better, it would rule already.
Only if you add some kind of fiber, i.e. spun glass, graphite, carbon, etc.could a 1/4 ply rib be coated in glue or epoxy to increase its strenght.