- Jun 28, 2020
I have looked through all of my references (Strojnik, Rutan, Arnold, Smith, et. al.) and cannot find indication of how to make really accurate wings with moldless construction. Strojnik talks about hot wire cutting foam then laying up skins that are prepared on a piece of plexi (great surface finish). Rutan talks about cutting the foam and glassing over it, then sanding it for surface quality. Arnold never really mentions it. If you assume the foam core is cut correctly (even perfectly) then even a really good laminate layup is going to have waviness and surface irregularity. What is the best technique to shape and verify the airfoil is accurate to +/- 0.010" (0.25mm) and the appropriate twist has been built in? Another way to ask is, can you build a moldless wing with the same quality as a molded sailplane wing? Just getting good surface finish isn't enough it needs to be accurate. I run into real problems trying to think through setting up some external reference system to control the dimensions. I am probably overthinking it.