Wing covering conundrums
I am recovering the wings on my 108-1 with the poly fiber method, and have some questions.
1. Screw spacing and location. Both wings have the screws spaced 6" on the bottom of the ribs root to tip. The chart from the book spaces them at about 3 1/2" outboard the prop arc and about 2 1/2" inboard based on VNE. This chart references lacing, which spaces the bottom & top sides of the wing close to the same. My 6" spacing is about double what the book says. Granted it's on the bottom where the pressure is pushing the fabric up towards the wing. Is the 6" correct on the bottom, or should I add screws to make the spacing 3"? I did not miss any screw holes. The tops of the wings are another issue. One wing has the screw spacing at 3" while the other has 6". Here I put screws midway on the 6" spaced wing - making them match the other wing at 3" (and agree with the spacing from the chart). Question is the riblets aft of the rear spar have no screws. The unscrewed lengths are 8"-14", depending which rib. Should there be screws on the top aft riblets? This is a long distance for no screws, especially on the top of the wing.
2. Tapes. If I put screws into the offset wing ribs, how do the tapes go? Do you use 3" tape to wrap the wing with one piece, or cut shorter lengths of 2" tape and offset them over the offset ribs? I realize it's an appearance thing, but what is common? Using 2" tapes all the way round the wing doesn't quite provide enough width past the reinforcing tapes if they're offset.
3. Fuel tank. The fuel tanks are not fabric covered because gas made the covering release in the olden days. Is it ok to cover the tanks now since the glues are much better than they used to be? With no covering over the tanks, is it ok to put a 3" tape over the strap to cover it since the gap around the tank gets covered anyhow? This seems like a good compromise for no fabric.
Thanks for any help.
1. The Stinson drawing for the wing assy, covered answers all these questions and more. Like where the inspection covers and drains go. (Yes, there's actually one on the top of the wing)
2. No screws aft of the aft spar, or on the ailerons.
3. Do yourself a favor and don't cover the tanks. If you get a leak, its way easier to remove the tank by peeling the edge tapes off than to redo the whole area around the tank. And it becomes a 337 for a major repair because you recovered an area more than three ribs, right? Why cover the straps? Just paint them
Thank you for the help. I looked at the service manual, and found no info. Where did you get the drawings? Haven't found them in searches. Thanks again.
Oh, and I covered the wings with the tanks out, so if I were to cover the tanks it would only be over the tanks as a separate piece.
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