I certainly would not weld up a hole in a wing attach fitting. There is no telling what would have in the way of small voids and/or cracks in the weld, soft or hard and brittle spots from contamination, etc. If it was welded you would need to remove any plating, use a 4130 welding rod, put on some extra material, then machine it down flat again, re heat treat it, and if I was flying it all would be done by a professional aerospace welder and it would get professionally inspected for cracks by X ray, eddy current, magnaflux, or whatever the correct method is. Admittedly, I may be going too far, but I certainly would not weld it and put my ass in the plane.
I remade a set of wing attach fittings for a Starduster 2 once. The holes to attach it to the spars were hand drilled so they were not perfectly spaced. I wanted the new holes to perfectly match the holes drilled in the wood spar so what I did was clamp the new undrilled fitting on my milling machine, put the old fitting on top of it and eyeball align the first hole and drill, put a bolt through both fittings to hole them together aligned, then one more hole at a time I found the center of each with a dial indicator and indicated and drilled one hole at a time. I think it took three or four hours to do eight fittings, but the result was new fittings that perfectly matched the holes drilled in the spars. Any machine shop should be able to do this for you if you have fittings that are not machine drilled to the exact spacing. Epoxied in dowels may also be acceptable, but been a long time since I have read the wood repair section of the 43.13. -------- Original Message -------- Subject: KR> Wing Attach Fitting questions From: Dave Acklam via KRnet <krnet at list.krnet.org> List-Post: krnet@list.krnet.org Date: Sun, January 24, 2016 11:35 am To: KRnet <krnet at list.krnet.org> Cc: Dave Acklam <dave.a.krnet at gmail.com> Ok... Since some folks here have a much better understanding of the 'design' behind the WAFs than I do... I'm not an engineer, and I don't want to die... So further experience would probably help Some questions: 1) What is the key force or mechanisim providing strength to the WAF joint? Is it the clamping pressure imparted by the bolts? The shaft of the bolt itself? 2) Is there a preferred method to 'adjust' a set of wing fittings that were drilled wrong? Would welding up the hole & re-drilling work? Bushings? Just make a new set? Any other info would be useful. I'm trying to mate wings from another KR, that I bought, to mine... _______________________________________________ Search the KRnet Archives at http://tugantek.com/archmailv2-kr/search. To UNsubscribe from KRnet, send a message to KRnet-leave at list.krnet.org please see other KRnet info at http://www.krnet.org/info.html see http://list.krnet.org/mailman/listinfo/krnet_list.krnet.org to change options
