Hello all,

I'm about to start cutting spruce for a wooden aircraft project. I've done some super basic woodworking projects around the house, so I'm familiar with the tools and general processes, but I've got a few base-level questions that I don't see addressed in most literature I've consumed. Maybe I'm just supposed to know this but I don't yet, so I thought I'd see what you all say. I want to make sure I do things properly to have good strong parts.

When cutting wood for an assembly, if you cut a piece just right and it fits together with everything else, great. But if it needs tweaking, can you sand it to fit? I’ve heard that can make the joint weak. Should you not sand at all and just get new material and do better next cut? Or if you have to sand a piece to fit in a joint or assembly should you do something to clean it before you glue it?

When you use the plywood for gussets, I’ve heard you should sand the sheen off. Is that literally all the more it needs, just a little bit to dull the surface? Doesn’t that fill the plywood with dust? Do you need clean out the grooves in the plywood before you glue it on?

Speaking of gusseted joints like a rib intersection: if some of the capstrip pieces are maybe a tiny bit different thickness than the others, do you sand the area where the gusset goes so they will all be at the same level and the gusset lays down flat? Like above, if you do, do you clean the sanded wood afterward before you glue the gusset on?

Thanks for the help, WIll