New builder here - sorry if this is a basic question!
So the RV14 has cover plates on the aft fuse which can be optionally dimpled. At that location, the countersunk nutplates (K1100-06) are installed on the vertical flanges of the aft most rib - I.e. the “parts sandwich” for the nutplate attachment holes would be dimpled nutplate attachment holes - dimpled aft rib flange - dimpled aft fuse skin and for the screw it would be countersunk nutplate - dimpled aft rib flange - dimpled aft fuse skin - dimpled cover plate - #6 screw.
In doing the dimpling of the #27 holes for the screws in the above sandwich (the screw holes, not the nutplate attach holes) I dimpled the wrong screw hole on the wrong rib, so needed to flatten it out.
But then got my ribs confused and flattened 2 of the 4 screw hole dimples in the above cover plate sandwich. Not really thinking it through, I then gently redimpled these holes...
I’m aware that you are not supposed to re-dimple a flattened dimple, but if I’m gentle...
In any case, there are minute cracks now along the inside lip of the dimple. Not all the way through the material, but through maybe half the material. I removed the paint from inside the dimples and can’t see any cracks there.
Here are some photos:
https://photos.app.goo.gl/KaCkJpVmrqvhLjG47
https://photos.app.goo.gl/DF7ESFonRkxq4ng57
So the question is / seeking opinions on how to proceed:
Given that the skin is held to the ribs by the nutplate attach holes, and the cover plate will be held firmly to the outside of the sandwich by the nutplate clamping pressure, can I just enlarge these cracked dimples to remove the cracks? I’m thinking that it is unlikely that screw pressure would deform both the cover plate and skin dimples below it into the slightly larger dimple below? (And cosmetically you would never see the larger drilled out dimple hole in the aft rib).
I.e. the sandwich would be countersunk nutplate screw hole - larger than normal drilled out aft rib flange screw dimple - aft skin dimple - cover plate dimple - #6 screw.
I appreciate everyone’s help - I know the easy thing is to order a new rib, but this takes a lot of time to Australia and shipping makes it probably a $100 exercise.
So the RV14 has cover plates on the aft fuse which can be optionally dimpled. At that location, the countersunk nutplates (K1100-06) are installed on the vertical flanges of the aft most rib - I.e. the “parts sandwich” for the nutplate attachment holes would be dimpled nutplate attachment holes - dimpled aft rib flange - dimpled aft fuse skin and for the screw it would be countersunk nutplate - dimpled aft rib flange - dimpled aft fuse skin - dimpled cover plate - #6 screw.
In doing the dimpling of the #27 holes for the screws in the above sandwich (the screw holes, not the nutplate attach holes) I dimpled the wrong screw hole on the wrong rib, so needed to flatten it out.
But then got my ribs confused and flattened 2 of the 4 screw hole dimples in the above cover plate sandwich. Not really thinking it through, I then gently redimpled these holes...
I’m aware that you are not supposed to re-dimple a flattened dimple, but if I’m gentle...
In any case, there are minute cracks now along the inside lip of the dimple. Not all the way through the material, but through maybe half the material. I removed the paint from inside the dimples and can’t see any cracks there.
Here are some photos:
https://photos.app.goo.gl/KaCkJpVmrqvhLjG47
https://photos.app.goo.gl/DF7ESFonRkxq4ng57
So the question is / seeking opinions on how to proceed:
Given that the skin is held to the ribs by the nutplate attach holes, and the cover plate will be held firmly to the outside of the sandwich by the nutplate clamping pressure, can I just enlarge these cracked dimples to remove the cracks? I’m thinking that it is unlikely that screw pressure would deform both the cover plate and skin dimples below it into the slightly larger dimple below? (And cosmetically you would never see the larger drilled out dimple hole in the aft rib).
I.e. the sandwich would be countersunk nutplate screw hole - larger than normal drilled out aft rib flange screw dimple - aft skin dimple - cover plate dimple - #6 screw.
I appreciate everyone’s help - I know the easy thing is to order a new rib, but this takes a lot of time to Australia and shipping makes it probably a $100 exercise.
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