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  #1  
Old 09-05-2016, 10:00 PM
rv6builder's Avatar
rv6builder rv6builder is offline
 
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Default Offset rivet set/ Crooked tails

Folks- I'm sure I'm not the only one who has been driven crazy by offset rivet sets. I'm riveting the forward top structure on my -6 and for some reason a lot of my shop heads have mushed over crooked, to the point that the edge of the hole is still visible around part of the rivet tail. Checked and double checked we are holding the gun straight, bucking bar is straight, rivets are the right length (even tried a few slightly shorter). Any ideas from the experts out there??

Cheers,

Alex
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  #2  
Old 09-06-2016, 08:37 AM
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Offset rivet sets are inherently very difficult to use. Make sure your work is extremely well supported. If your not making smiley's on the factory head, there is something else wrong. Too little air pressure at the gun, bucking bar not heavy enough, etc.... would be things to look at.
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  #3  
Old 09-06-2016, 08:43 AM
StuBob StuBob is offline
 
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Quote:
Originally Posted by JonJay View Post
Offset rivet sets are inherently very difficult to use. Make sure your work is extremely well supported. If your not making smiley's on the factory head, there is something else wrong. Too little air pressure at the gun, bucking bar not heavy enough, etc.... would be things to look at.
Is this what you're saying: If the problem was that the offset set was hitting the heads at an angle, he'd be getting smilies. If he's not getting smilies, the problem isn't directly related to the offset rivet set.

Excellent point.
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  #4  
Old 09-06-2016, 08:58 AM
nilberg nilberg is offline
 
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Two other contributing factors are:

- Rivet not 100% straight in the hole due to slight misalignment of the layers. So even if the bucking bar is normal to the surface, there is a misalignment between the force from the rivet gun and the bucking bar.

- Rivet a little too long.

Most of my crooked rivets are a combination of the two above.
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  #5  
Old 09-06-2016, 09:03 AM
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Thanks for the info guys- Ill give it another try after work today. Cheers!

Alex
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  #6  
Old 09-06-2016, 12:28 PM
Tom Martin Tom Martin is offline
 
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another common problem is the offset rivet set trying to turn during riveting. Use electrical tape and securely tape the set to the gun so that the set can not swivel.
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  #7  
Old 09-06-2016, 12:31 PM
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Quote:
Originally Posted by Tom Martin View Post
another common problem is the offset rivet set trying to turn during riveting. Use electrical tape and securely tape the set to the gun so that the set can not swivel.
Or hold it with your fingers if another person is on the bucking bar.
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  #8  
Old 09-06-2016, 01:03 PM
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All good discussion regarding an offset rivet set, but as mentioned, if there is not visible damage or influence to the manufactured head, it is not likely caused by what rivet set you are using.

Rivet length, enlarged holes or bucking bar technique (or a combination) are more likely causes.
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  #9  
Old 09-06-2016, 05:36 PM
rv7charlie rv7charlie is offline
 
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Alex,

What everybody is dancing around, is that an 'offset rivet set' is a tool with at least one; usually two, bends in it, that is inserted in the end of your rivet gun. The posts describing 2 people holding one rivet gun are talking about that. I'm pretty sure they were created by guys looking for a good deal on a slightly messed up pre-owned kit.

A shop head that sets off-center or bent ('clinched') is likely what you're asking about. As others mentioned, bucking bar alignment is important, but keeping the bar from 'wiping' across the shop head is also important. If it moves sideways during riveting, it can move the shop head with it.

Charlie

Last edited by rv7charlie : 09-06-2016 at 05:38 PM.
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  #10  
Old 09-06-2016, 05:59 PM
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The problem with the longer rivet sets is that they have more mass than shorter rivet sets. I had to really bump up the air pressure whenever I used an offset rivet set. Try using 75 psi on some scraps and see if it helps get the rivet bucked quickly. If you have to pound away at it with lower pressure, the rivet will work-harden and then the tails will tip over instead of smoosh smoothly.
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