Wing root bolt hole slop

[Bluebird19kf]

I inspected my wing root bolt hole and found the spare hole to be really sloppy. The fuselage hole is nice. What is the best way to fix this. My first thought was to rivet new steel backup plates in and re drill the holes. Tried searching but didn't see much info. Holes have probably 1/16 of play!!!!

[Esser]

I think you are on the right track with that idea. I would also put some hysol between the two plates so when you drill the hole, the old hole in the spare with slip is filled in. Best bet would be to call the factory.

[Bluebird19kf]

I talked to john at kitfox. He said AC 43.13....but the way the newer foxes are they put 2 steel doublers instead of 1 on the spars with hysol and micro balloons(controversial)and cherry max rivets . I feel like I am going to put 2 new doublers on with hysol and microballons out of 4130 with cherry max rivets and call it real. Now I just need to figure out the best way to line up and drill the holes perfectly. I'm liking the attach something to the fuselage carry thru tube with the hole and mimic that. Please comment with other words of wisdom. Thanks

[jiott]

I would suggest when you drill/line-up the holes in your new steel doublers you follow the same procedure in the manual as if this were a new build. Since your old holes are all wallowed out there is nothing there you can count on. Using the original rigging procedure will insure the wings are lined up (leading edges) and symmetrical (diagonal measurements from each wingtip to rudder post).

[WISDAN]

I agree with jiott, follow the rigging instructions to drill the holes correctly. I have re-inforcements that are completely circular and fit the inside I.D. Of the spar. I bought them from Blue Sky Aviation, don't think they are in business anymore. May be another optiion if you can find them. Two doublers should work out, good luck!

[redbowen]

Wisdan do you have any pictures of that set up?

[DesertFox4]

I have seen the stainless repair inserts WISDAN speaks of years ago. I also believe they were from Blue Sky Av.
I saw them at Murle Williams (Williams Aviation in Phoenix, AZ.)
Murle had a set but I am not sure if he used them or not in a spar repair. You might give him a call. 602-978-0553.
The spar repair inserts looked very high quality.

[airlina]

I believe these are the inserts you are talking about. When I was building back in the late 90's there was a guy in Colorado that made aftermarket stuff for the Kitfox and these SS wing spar root inserts were one of the items. i used them on my Series 5 . Was a slick setup as they were a nice tight fit in the spar and were glued and riveted in place. Weren't cheap though at 330 bucks and history has shown in the great safety record of the Kitfox that they were probably overkill and the current design has served well. Bruce N199CL

[DesertFox4]

Bruce, yes those are the ones I saw at Murle’s many years ago. Really they were overkill but a neet solution for a miss drilled hole or worn ones.

[WISDAN]

DesertFox 4 is correct, the inserts were designed to repair damaged or mis- drilled spar holes. Not really needed for a normal wing build as the kit supplied spar doublers are more than sufficient.