RV-14A Bellcrank Rib Dent

[Tilford]

While riveting the left bellcrank rib to the aft fuselage forward bottom skin, my bucking bar slipped and did some damage to the rib. I'm planning on replacing the rib, however, I thought I'd check here to see if there were any other thoughts on how I might proceed on this one?

Thank you,

[DGlaeser]

Where exactly is the damage? I don't see anything worrisome in that picture.
In general unless the damage is substantial, removing and replacing stuff causes more damage than the original 'problem'.

[Lionclaw]

It's just to the left of the metal rule, between it and the dimple, if I'm seeing it correctly.

I'll let others chime in on the dent, but it looks like there might be some small cracks in some of your dimples.

[clutch22]

When I was finishing my QB wings, I had one or two bar marks. On mine, I took some excess J-stringer material I had laying around and cut off the "J" part of it and installed it, nested over the discrepant location. Then if you add a rivet midspaced on both sides that will take additional load off the discrepant location. In the upright leg of my nested angles I installed some blind rivets to tie it to the rib web. I also fay sealed the angle.
Since everything is all riveted together, on the added rivets, I would use 1097 "shallow head/ oops" rivets instead of dimpling the stack-up.

[Tilford]

Andy, I saw that too when I first looked at the photos a few days ago. I inspected both bellcrank ribs and found, what I believed to be, cracks on 5 dimples. I drilled out the rivets from those holes and ran a scotchbrite pad over the supposed cracks and they all vanished. I suspect what we're seeing in the photo may have been marks from my deburring tool.

Thanks,

[OLDSAM]

If you replace every part with a riveting set or bucking bar ding, you are going to be older than me when you get done, or else you have really steady hands.

[Tilford]

OldSam,

I have a few small dings that I sand down and let go, however, with this particular ding, I'm concerned because, where the dent is, the thickness of the material is reduced by about 50%. I figure that by replacing the part now, I may be saving myself a giant headache later if the part were to crack after the plane is flying.

Your point is well taken though,

[bill@fusion4.net]

Originally Posted by Tilford

OldSam,

I have a few small dings that I sand down and let go, however, with this particular ding, I'm concerned because, where the dent is, the thickness of the material is reduced by about 50%. I figure that by replacing the part now, I may be saving myself a giant headache later if the part were to crack after the plane is flying.

Your point is well taken though,

I would think a doubler on the 3 rivets shown would be plenty of protection. But I am not an engineer, so probably not even worth 2c.

[greghughespdx]

Did you ask the good folks at Vans? My *guess* is they advise you to "keep calm and build on," but would probably be the best place to check with them just in case there's actually any structural concern.

[Tilford]

I did check with Van's. They were a bit vague on this one I suppose, but answered the question I had sent them. I took the response to mean, replace the rib.

Question: "Good morning Sir,
While riveting the left bellcrank rib to the aft fuselage forward bottom skin, my bucking bar slipped and did some damage to the rib. May I get your opinion on the damage please and a suggested repair if one is required."

Answer from Van's: "It's impossible to say what might happen here in the future, other than if the rib ever does crack, this is the obvious place for it to start. The simplest repair is to replace the rib -- trying to create patches can lead to more problems than it solve.

You might want to set your rivets just...a ...little more -- although photos can be deceiving.
Check them with a rivet gauge."

Also, in response to Van's response, I re-checked my rivets with a rivet gauge and they were good.