ORIGINAL: Michaelj2k
What is the possibility that the tabs shown on each rib are actually a long support that is shaped to match the airfoil and attached to the building board and not part of the rib? When the wing and stab are under construction, the support which would be as long as the wing panel, is used to pin the rib down to hold it in place while the spars and other associated parts are being assembled. If you look at a picture of supports for ships in drydock, you will see what I mean.
Another thing I see is the support is extended into the sheeted area of the ribs. Were the balsa skins pinned the building board supports then ribs, spars and associated parts added? This method would certainly insure proper wing alingment and automatically build in the required washout and anhedral.
I don't know of anyone using a technique like this.
The way I see it, the tabs on each rib, and the extensions of both the main and minor spars are in contact with the building table as they come together in "eggcrate" fashion. Once together, the bottom sheeting is applied to hold everything together, then the wing halves are flipped over and the tabs removed. It is possible that the anhedral is already figured into the support tabs, (we'll have to see from the plan how it comes together), so that only the root ribs and spars require some sanding where they join. The bottom sheeting then holds everything in place while the top sheeting is applied.
One thing we know to do is to cut all the ribs and spars with the tabs as shown, and alignment
should be correct. I assume Tom did all that figuring for us in the plan, so that only assembly is required. That's the hope at least.
I'll start working on the photos I took the other day to get them ready to put in the thread.
Duane