We're just tooling up to rebuild a set of wings for a friend's 7AC that got flipped over (after I FINALLY got it rigged just right!!!) Does anybody know the correct size and length of the nails for attaching the wing ribs to the spars, and what is the correct procedure for placing and making the tramelling marks in the spars?
We're just tooling up to rebuild a set of wings for a friend's 7AC that got flipped over (after I FINALLY got it rigged just right!!!) Does anybody know the correct size and length of the nails for attaching the wing ribs to the spars, and what is the correct procedure for placing and making the tramelling marks in the spars?
I used the nails called out in the L16A parts list which is AC301-18-5. I purchased way too many. I will be happy to sell you a pound of them for what I have in them + shipping.
Others here have used other nails for various reasons.
Dan, sorry it took me so long to reply. Been a little nuts around here lately. For squaring the wing, we use the center of the inboard bolt holes in the butt fittings. On the outboard, the center of the bolts for the most outboard compression fitting. Put a little indentation in the spar with a scribe for the points to go in. If you square each bay, use the compression strut bolt centers.
I only square the entire wing, not each bay. If you use a string on the spars to be sure they are straight, you don't have to check each bay. As for nails, please consider using something larger than the original 18 guage(print calls out cement coated). I built my first set of wings in 1985-86, and flew them 3-400 hours. Sometimes pretty hard. When we took them apart last year, several nails around the rear spar at the aileron fell out on the floor. Lot's of loose nails too. Later model airplanes had lots of nail problems.
The new nails everyone sells are 14 gauge ring shank nails per Service Letter C-139. This is for the later airplanes but everyone treats the 7AC's the same. Including Bill Pancake. The new nails are borderline too long, if not shortened a little they will poke out the other side. I have been using 15 guage SS ring shank nails from Jamestown Dist.(a marine supply). The 14's look huge to me.
Does anybody know the correct size and length of the nails for attaching the wing ribs to the spars, and what is the correct procedure for placing and making the tramelling marks in the spars?