Dealing with a Bad Rivet

[jchang10]

Hi Everyone,

I finally started using my pneumatic squeezer, and i have my first bad rivet. I managed to drill out the AN426AD4-7 but left some scratches around the countersunk hole.



Any advice on how i should clean up this scratched up hole? Given all the care we take to remove all machine marks and scratches, it seems like i should try something.

At this point, I figured i would:
- drill the hole using the same #30 drill but circle the hole a bit to clean up the edges.
- run the countersink again to clean up the flared edges
- respray with primer
- retry the rivet

Any advice would be appreciated!

Jae

[jcoloccia]

Originally Posted by jchang10

Hi Everyone,
- drill the hole using the same #30 drill but circle the hole a bit to clean up the Jae

definately don't do that. You'll just make the hole bigger and then you'll never get the rivet to drive straight. I went out to your site and saw your pictures. Doesn't look bad at all...I'd just rub it out with some emery cloth and a scotchbrite pad, shoot some rattle can primer for touch-up, and try again. Wear a mask when you do this...If I read correctly, you happened to use Zinc Chromate on this part. The dust is not all that good for you.

I'm sure 10 different people will have 10 different ideas what to do here, but there's mine at any rate

[RV8RIVETER]

I agree, do not run drill in there again, unless you intend to go a size bigger, which really isn't necessary. You can run one revolution of countersink and lightly sand scratches and reprime. No big deal.

As a side note, FYI, since we didn't see the rivet. When you get to thinner sheets, you don't want to be too quick to drill out an "unperfect" rivet. If one is set on the edge of the spec, you can do more damage drilling out than leaving the rivet alone.

Good luck and happy riveting.

[jchang10]

Thanks again for the advice. I'm going to take more care to set these rivets, since taking it out was not as easy as i had hoped.

Also, how many spare rivets are we given to make mistakes or practice? I should have practiced more on scrap, but i wasn't sure how many spare rivets i would have.

This set of AN426AD4-7 came in a plastic labelled bag.

Jae

[jcoloccia]

Originally Posted by jchang10

Thanks again for the advice. I'm going to take more care to set these rivets, since taking it out was not as easy as i had hoped.

Also, how many spare rivets are we given to make mistakes or practice? I should have practiced more on scrap, but i wasn't sure how many spare rivets i would have.

This set of AN426AD4-7 came in a plastic labelled bag.

Jae

My experience so far is that you have way more than enough rivets to screw up all you like And if you run out, you can just order more. I ordered the rivet assortment from aircraft sprice when I started (be sure to get the hardened ones). Rivets are cheap.

re: drilling out rivets. After you pop off the head, take a drill a couple of sizes smaller than the hole and CAREFULLY drill through the center of the rivet shank. This relieves the pressure on the sides. Then back it with a piece of wood, and the sucker should pop right out with a couple of firm taps.