A real RivetBangers question

JOHN TIPTON · Post by **JOHN TIPTON** » Wed Nov 26, 2008 5:53 am

Hi

Have any of you guys slow (Rv9a in our case) building had any experience of rivets going off with age - resulting in both sqweezed and 'bucked' rivets not being 'ideally' set

Regards - John (England - wings RV9a)

captain_john · Post by **captain_john** » Wed Nov 26, 2008 8:01 am

John, I would love to blame the rivet sometimes too! Fact o' the matter is... naw. They are fine and don't have any age limitations on them (at least this is the case for our AD style rivets).

I DO try to remove all the clubbed ones from the tray before I try to set them though! (sarcasm!)

CJ

weezbad · Post by **weezbad** » Wed Nov 26, 2008 8:25 am

john i know sometime they seem like they just dont want to shoot right but the problem can usually be traced back to operator error.
i have rivets that are left over from from army surplus that were probally 20 years old when i got them. i have had them for 19 years myself and they will shoot perfectly fine.
the only scenario i can imagine, and its a far fetched one at that, is if they were somehow heated and cooled. not just to 90 deg ands 30 deg but a much wider spectrum. yeah i said it was a far fetch.

if you are shooting on thin material, esp on a rib or similar where there is a web, a little too much pressure will cause the open side of the flange to angle away from the gun thus tilting the rivet and leave you with a shifted shop head. i have seen this many times and is likely the most popular problem for people. whoever is doing the shooting needs to insure they are not pushing the gun to much towards the work surface. a friend was helping me and i could see the metal move when he would hold the gun up to the surface, this was enough to cause the problem. this is also why a lot of people use reamers and also one size smaller bit to matchdrill the holes.
i hope this didnt come across remedial but sometimes the problems are easier to fix than we think. YMMV

Wicked Stick · Post by **Wicked Stick** » Wed Nov 26, 2008 9:26 am

I remember a few rivets that split when bucked, but I'd say it's more a random defective rivet than age.

Post by **Spike** » Wed Nov 26, 2008 9:34 am

I find that most of the time my problem rivets are because:

1) I wasn't lined up on them squarely
2) I used one that was too long.

I dont know of any age problems though. The ones we use are mostly all aluminum. If they have problem with age I'd be worried about the aircraft metal as well.

weezbad · Post by **weezbad** » Wed Nov 26, 2008 10:37 am

Wicked Stick wrote:I remember a few rivets that split when bucked, but I'd say it's more a random defective rivet than age.

ive had this happen a few times. the rivet would split on a line 10-20 deg or so from the length wise axis. it was usually cold in my shop however, but it was likely caused by a side loaded die. only happened when using the pnuematic squeezer.

flytoboat · Post by **flytoboat** » Wed Nov 26, 2008 10:50 am

So get some new rivets and do a side-by-side comparison.

Wicked Stick · Post by **Wicked Stick** » Wed Nov 26, 2008 9:05 pm

weezbad wrote:
Wicked Stick wrote:I remember a few rivets that split when bucked, but I'd say it's more a random defective rivet than age.
ive had this happen a few times. the rivet would split on a line 10-20 deg or so from the length wise axis. it was usually cold in my shop however, but it was likely caused by a side loaded die. only happened when using the pnuematic squeezer.

Mine occured while bucking. Pretty rare though, maybe 3 or 4 that I can remember tops out of the whole airplane build.