I?m feeling flattened (and dimpled again)

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.

253 views but no one can help?

Maybe my post was too long?

I think if you post a picture showing how the parts attach to each other that will help.

I dont see any problem with making the screw holes slightly bigger to remove the cracks. It's just a cover plate.

Maybe this might help:

https://photos.app.goo.gl/AxCYKARovHx5eExr6

That's picture helps. I dont think it's worth worrying about. I vote build on. I've dimpled things the wrong direction by accident, then un-dimpled it the opposite direction and havent experianced any I'll effects.

I ended up with cracks on the horizontal J channel on the Bottom. Vans said not an issue. But I would ask the experts on this one as that's your aft bulkhead basically. It's way easier to replace now if you have to, than after its built.

My 2c

Trent, I wouln't be too concerned about this. I am sure many builders have made this mistake. I did.

In the case of nut plates the screws pass through the holes, the strength of the connection it in the nut plate and the material clamped to it.

And I would always say that technical advice should always come from the factory first. Do not rely on the opinions of people on these forums. It is a great source of information, personal experience and discussion but the vast majority of us here are interested amateurs. And I say that with the greatest respect, but that is what we are.

Thanks Peter,

I understand. The first thing I did was email the mothership, but have not heard back as yet. The next step is my TC.