Stainless Rivets in the Stainless Firewall

[MotReklaw]

I'm having a problem getting the rivets to seat properly. I'm using a manual riveter and two pneumatic riveters. None will consistently pull the rivets up tight. Out of about 20 rivets I pulled this morning 19 were loose enough to have to drill out. Some moved up to 1/8". it seems the problem is that the two stainless pieces total about .038 thickness while the 1/8 rivet is .125". Is there a trick to get the rivets to pull correctly. I've popped about 20,000 rivets in the past 10 years, mostly aluminum, and this is the first problem I've had.

Any tips on getting .125 to compress to .038 is appreciated.

Thanks,

[jamesmil]

try useing a 1/8" thin washer over the rivet on the back side to take up some of the clearance. hope this helps:)

[MotReklaw]

James, that's a great idea!

I sometimes don't think of the obvious...

Thanks!

[HighWing]

One more thought. I have squeezed lots of SS with both hand and pneumatic squeezers with no problems. I wonder if you have a bad run of rivets. I know the mandrel is scored to provide a predictable break point, maybe the fabrication adjustments were a tad off. You might want to try another batch of rivets.
Lowell