Center Rib Probem

[Bucky]

I have an issue that I was hoping to get some advice on. I am currently building the .024 center ribs with the aft oval lightning hole. The problem is, when I placed the jig hole for the tooling, I placed it with the round lightening hole in mind. When I started to make the oval hole template I noticed that the jig hole is less than 1/4 inch from the lightning hole and will therefore be in the flange. I think I know what the answers will be, but wanted to ask someone more experienced than me. Soooooo, is there a fix, or do I need to repurpose these ribs into something else? Sent from my iPhone using Tapatalk

[bestbearhawk1231]

Hi Lance, I did something similar on my full length ribs. I ended up remaking them and using the old ones to remake a couple flap back ribs I misdrilled as I went along. You could try deburring the hole and flanging it to see if it will crack. My guess is that it will end up cracking when you flange it or later in life due to vibration. In my 43.13 I vaguely remember a method for repairing a cracked rib using a doubler riveted to the rib. If you go that route, it will add weight, time, and complexity to your build. You may just want to bite the bullet so to speak and chock it up as a learning experience. You can get a lot of your attach angles out of them if it makes you feel any better! Hopefully others will chime in. Try deburring the hole and flanging one to see where the hole ends up, worst case is that it cracks.

[Bucky]

Thanks. I had the same thought. Didn't want to go the doubler direction simply because I didn't want to add that to the build. Probably just going to repurpose them into flap ribs or something. The hole is just too close to where the radius other the flange will be. Thanks for the reply! Lance Plans #1309