I first tried using the Cleaveland tools “Tight-Fit dimpling Mixture” and it was very scary and tough to do. I carefully used the ram for the C-Frame tool and then drove the male end into the female mounted dye. It worked Ok but the nut plates were not sitting as flush as I wanted. I tried to hit them again harder but it was not effective enough to proceed with the flush rivets Called out in the plans.

So I decided to grind down my female dye after looking at the small amount required to make it fit and be able to use my hand squeezer. I marked the edge so I could line up the nut plate.

With the mechanical advantage of the squeezer these nut plates came out great and they stayed flat. Really pleased with the results so I thought I would share.

Allen
RV-14A (Elevators step 2 Page 09-12)

Hmm I've always just dimpled them with a squeezer, seem to get good results.

I've used a ton of different kinds of nutplates and never had to tap one; Boelube alone has always done the trick. Maybe it's necessary some times but it shouldn't be done as a matter of course. There are good reasons not to compromise the self-locking feature.