How to use big rivet to seal fuel tank tooling holes?

[IowaRV9Dreamer]

Hi - a fellow builder has given me a few AN470AD6-7 "big" rivets to use to close up the tooling holes in the outboard fuel tank ribs.

Even though these are the shortest 3/16" rivets that Vans sells, I think they will be way too long to use as-is. The fuel tank ribs are 0.032 thick. If I understand rivets correctly, I need to have 1.5D protruding prior to setting the rivet, or 0.281. Adding that to the rib thickness gives 0.313 which is about a -5 rivet.

My question is - what is the easiest way to remove 1/8 inch from a rivet without a rivet cutter (I'm too cheap to buy one for only 2 rivets). I have only a very few, so I can't experiment too much.

Thanks!

[jchang10]

I think it took probably less than 30 seconds per rivet with a hacksaw. Too obvious, i know!

[Thermos]

I used longer AD6 rivets as well. I wasn't too worried about getting the length exactly right, since the rivet isn't doing anything structural - just plugging the tooling hole. Plus, it will (or should, at least) get covered by Proseal.

If the rivet is too long to set at all, you could use a disk sander or even a file to shorten them. Just be careful if you use the sander, those rivets get hot!

Hope this helps...

Dave

[kentb]

This is not structural, so I used a #4 rivet and prosealed it good. It is not going to fall out even though it didn't fit the hole.

Kent

[IowaRV9Dreamer]

Originally Posted by Thermos

If the rivet is too long to set at all, you could use a disk sander or even a file to shorten them. Just be careful if you use the sander, those rivets get hot!

That was my first plan, but I was afraid of the heat changing the temper of the rivet, causing it to become unsqueezable.

The other poster is right, I "forgot" these aren't structural, so maybe I can squeeze them at the longer length.

Love these forums - three ideas in just a few minutes!

[jcoloccia]

Is there a reason not to used a sealed blind rivet?

[alpinelakespilot2000]

Originally Posted by IowaRV9Dreamer

That was my first plan, but I was afraid of the heat changing the temper of the rivet, causing it to become unsqueezable.
!

I don't think they become unsqueezable--actually they squeeze (or buck) a little too easily causing them to flatten out too much if you hit them too long. I haven't heard anything about the heat causing any long-term strength problems though if you grind off a little before bucking it. Anyone else know anything about this?

[Paul Thomas]

Rivets work harden, which means that if you heat them up, it becomes very difficult to set them. I'd try with a longer one first, as long as you plug the hole, you're done.

Pop rivets would work just fine and it won't be visible once it's on the airplane.

[airguy]

"Work hardening" is not caused by heat, it's caused by rearrangement of the micro-crystalline structure of the metal due to mechanical deformation. Heating it may affect the temper, but it won't "work harden" the metal.

[cytoxin]

cut it with a hack saw, put it in the hole, and smack it a time or two, enough to put some set in it and cover it with proseal. at least thats how i did it.