Riveting. What on earth am I missing?

I've been riveting a body together. Four hundred or so rivets in, all was OK - insert pop rivet, squeeze riveter, repeat. Then my Stanley riveter exploded (I think something came unscrewed, so when the rivet mandrel snapped, it launched the riveter's internals everywhere).

Since then, everything has gone downhill. I switched to using my lazy tongs riveter - OK for a while, but then it began snapping stems at half height - they would neck down and fail in tension. I bought another "normal" riveter but as a Screwfix own brand unit it wasn't very stiff. I swapped the internals into the vacant interior of my Stanley but that began snapping rivet stems at half height too. OK - bad rivets; it had only started happening since I got a new box. I took the new box back and bought some from Machine Mart instead. Much better at first, but gradually they started to exhibit the same problem!

I worked around it for a while but it's gotten steadily worse until only one in four or five is actually going in correctly and it's taking an hour to set twelve rivets. Clearly this is ridiculous. I've now bought another good Stanley riveter; so far I've fed it two rivets and it's not set either as it should.

So - four riveters from three suppliers, two types of rivet from two suppliers. They're all 4.8mm aluminium rivets which I'm installing into 5mm holes in aluminium bodywork. Previously I could machinegun them in without any difficulty or particular finesse - they just went straight in. Now nothing works. What am I missing?

One final piece of the puzzle - I have some large flange head rivets that I use less often. These... seem to work.

I don't know what you're missing. Maybe buy another stanley ? ...

I lost interest in "manual" rivet doohickies years ago, and use an air hydraulic one now - think it's a CP ( Chicago Pneumatic ), and it caused a few drinking vouchers to change hands, but it was worth it.

Two Stanleys is enough for me - the original (rebuilt) one, and a brand new one bought this morning that did the same on its first rivet. At least that appears to rule out its being the riveter that's at fault. I'd conclude that I was the common thread in all this, but I managed literally hundreds before this started to happen, and it's been happening for me and for my daughter too.

I hate diagnostics...

The holes are too big. You need BH rivets and not BS rivets.

Interesting. Hopefully it's that simple. I'll switch from 5mm to 4.5mm and give it a go.

..BH vs BS?

thetim said:

Interesting. Hopefully it's that simple. I'll switch from 5mm to 4.5mm and give it a go.

Click to expand...

4.8 rivets are 3/16. You need a 3/16 drill bit. All you need to do is drill the hole then stroke the bit in and out a couple of times to give clearance. Rivets should be a tight fit in hole not flop around in it like a whippets dick. Break head rivets are better than break stem but they need filler applied to seal them and flush head. Either that or the rivets are too long for the material being fastened. That would certainly cause stem protrusion.

Ah, break head rather than break stem - makes sense
I'm confident that it's not the length at least - I'll report back once I've got the drill size down.

I reduced the hole size to 4.5mm and then expanded it until the rivets just went in; they snapped with depressing consistency. What seems to have worked is modifying my lazy tongs riveter so that it reliably sets the rivets fully in one stroke. Good to be functional again (for now at least...)

I'm still confused as to why a technique that worked for hundreds of rivets suddenly became so unsatisfactory. I'll certainly be careful with the drilling and will get some 3/16 drills on order by way of limiting scope for variation.

This is riveting.

Sigh

> I'm still confused as to why a technique that worked for hundreds of rivets suddenly became so unsatisfactory

Any major changes in ambient temp?

You said yourself that it occurred after changing rivets. Ime rivets from screwfix/mm are pants and I bought all mine off eBay. I can dig out the supplier if needed but think it was Kay's fixings or something. Sealed rivets int body and never use rivets that are too long or Stem protrusion as mentioned above will occur.