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Priming and riveting dilemma

chaliboy

I'm New Here
Just started riveting parts after prime painting.

Question, rivets do not fit without applying much force. Seems that the paint
Inhibits the rivets from going through without some extra effort. The holes were
Previously drilled and deburred.

I’m I doing something wrong ?
 
Assuming your talking about non-dimpled -4 rivets with #30 holes?

In a perfect world, a #30 drill bit leaves a .1285 hole A -4 rivet is .125. In other words, if it's perfect, the hole is only .0035 bigger than the rivet you're trying to stuff in it.

Obviously there's going to be some slop from holding the drill crooked, machining tolerance of the bits, rivets, etc. but yes, the primer can make the hole too tight to get a rivet to drop in. (FYI- per mil-spec, the allowable hole size for a -4 rivet is .125-.135)

I typically prime before match drilling, so there's no primer in the hole. But if you choose to do it the other way it's not a big deal. If you can't get a rivet in and you're sure the hole is final size and didn't get missed when you were match drilling, its pretty simple to just twirl the appropriate side drill bit between your fingers and clean the primer out of the hole.
 
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If primer is applied too thick (or just beads on the rivet holes) it can make it difficult to push the rivet through. Just twirl a reamer in the hole freehand to clean out the little bit of primer in the hole. No big deal.

Without photos it’s hard to help diagnose the true issue but doesn’t sound like a show stopper.
 
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The layer of primer should be really thin and not impact the size of the match drilled hole. Are you spraying it on too thick?
 
I think that I might be applying it a little thick.
Will use the reamer to remove primer from hole.

Will make adjustments.

Thanks you all.
 
Using steward system.

I had the same happen to me when I was using Stewart System's Ekopoxy. I eventually switched to a different epoxy primer because I could get it locally, and I still occasionally have that problem but not as often because I've gotten better at keeping the primer coat thin.
 
Instead of a reamer or drill bit, I like to use an awl, punch it in, and wiggle it around. If that doesn’t work, then I do the drill or reamer thing.
 
The surface tension of paint causes it to be attracted to edges, where the excess extends beyond the edge. Thinner coats should help.

Larry
 
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