gap between spar flange and skin

CalKid · Post by **CalKid** » Sat Feb 28, 2009 12:52 pm

Had a hole problem with the HZ skin along the front spar which resulted in drilling the hole to 40 and using a 1/8 rivet. When I set the rivet, because the dimple didn't quite accept the Mgf head of the rivet, the spar flange in the area of this hole is not flush with the skin; slightly curved. I see further problems if I drill this rivet out. I'm thinking build on. Any advise appreciated.

Post by **bullojm1** » Sat Feb 28, 2009 2:11 pm

Is what your saying is there is a #40 dimple, drilled out to a #30 hole with a 1/8" flush rivet in it? if so, yeah that's a problem. Probably not catastrophic, but the fix is probably to remove enough rivets so you can dimple both the skin and the spar to #30. I can't remember is the spar is dimpled or countersunk. If it is countersunk, you probably might need a doubler on the shop head side of it.

Anytime you have non-contiguous (i.e. wavey) contact between two pieces riveted together, there is loss of strength.

Post by **Spike** » Sat Feb 28, 2009 6:11 pm

Or if that is the case you could pull out that one rivet and replace it with an 'oops' rivet.

Spike

Post by **bullojm1** » Sat Feb 28, 2009 7:10 pm

Is it just one rivet or a whole row of them? In my original post, I wrote it interpreting the original message as a whole row done this way. Now that I reread it (with Spikes input), if its just one rivet, the NAS1097AD4-x OOPS rivets are the way to go. They have a #40 rivet head and a 1/8" shaft.

I would order a whole slew of oops rivets - http://www.vansaircraft.com/cgi-bin/cat ... oduct=oops

If I were you, I would order 0.05 lbs of each. They will come in handy down the road.