Should it stay or should it go?

GKnut · #1 06-20-2012, 08:26 AM

While drilling the HS-405 to the forward spar, I didn't realize that the -405 moved, even thought it was clamped and ended up with an extra hole, as you can see from the pic. Question is. Can I ignore it as unsightly but not having an impact on the structure, or, due to it's proximity to the hole where the rivet will reside, it will weaken the integrity of the area? Thoughts?

http://i172.photobucket.com/albums/w...k/DSC01531.jpg

flion · #2 06-20-2012, 08:32 AM

I'm assuming the extra hole is in the rib only, not the spar. In that case, deburr, rivet, and move on. Yes, that one rivet will have poor edge distance due to the proximity of the hole but it should not significantly impact the overall structure. Playing devil's advocate, though, a replacement rib is pretty cheap.

Bob Axsom · #3 06-20-2012, 09:14 AM

I made a decision early in the building of our RV-6A that there is a repair for any mistake and committed to fix instead of replace. I would probably come up[ with some kind of doubler to fix this. No way would I consider this scrap - that's just wasteful.

Bob Axsom

JonJay · #4 06-20-2012, 09:19 AM

Fix it. Cut off the flange, bend a replacement, and rivet it on. Quick and easy. This is common practice and an acceptable repair even in the certified world.

GKnut · #5 06-20-2012, 09:34 AM

A doubler sounds like the most prudent. I could order a replacement but the world has only so much aluminum. Thanks for the input all!

JonJay · #6 06-20-2012, 09:51 AM

Quote:

Originally Posted by GKnut

A doubler sound like the most prudent. I could order a replacement but the world has only so much aluminum. Thanks for the input all!

A simple doubler would probably work, heck, leaving it the way it is would probably not be a big deal. However, since the errant hole is in the radius of the flange, the proper repair would be to replace the flange or use a doubler shaped like the flange and riveted to the rib web.
AC-43-13-1b shows many examples of repairs to structure, including flanges. If you make a doubler for this area, the doubler would essentially be another flange nested into the existing flange. It seems easier to me to cut off the offending flange and rivet a new one on. Same amount of work and cleaner.
Not trying to make a mountain out of a mole hill, but learning the proper repair techniques early will help you evaluate other situations down the road.