is it ok to use self tapper screws on alloy panel under bulkhead the one the battery sits on ?
Presume you mean th plate that holds wiring/fuses and stuff that can't be seen, Into the chassis tubes?
Not everyone's choice but reason why not as long as they grip ok
If you're going into thin sheet, no. They won't grip and will become unreliable. I'd go for nutserts for thin panels and then a good
old fashioned socked-headed cap screw. Even then, nutserts can be unreliable, and you have to be careful to get a very high-quality hole (I generally
under-drill by 0.5mm and them ream). Socket headed cap screws are also more reliable than the black self-tappers. You don't run the risk of
damaging the cross-point because there isn't one. The socket head is supported on all sides. Westfield fasteners sell this stuff by the thousand,
and it's dirt cheap.
Rivets are OK, but they're a one-way deal. Rivnuts give you a good compromise. Yes, you can drill a rivet out but it's a pain, worse if they
spin, and sometimes you end up with crap rattling around in the chassis, or a larger hole than you started with.
I don't like self-tapping screws going into the chassis - again there's generally only 1.5mm for them to bite into and I've had enough
work free. If you have to remount something, the screw thread will wear and you will eventually have a spinner. What's more, they create a
stress-riser and cab be an ingress for water.
My favorite route now is to bond a bracket of some kind in place, or (and this is only if you can), I use a nutsert, then put a tiny tack of weld in
to hold it. You can only really do this with tig. Once the bolt has been tightened into this the compressive force gives you a strong bind.
If you want to start getting deeply into this, check out
Prepare To Win by Carroll Smith - it's the bible on this stuff.
quote:
Originally posted by FuryRebuild
I'd go for nutsertsl....
Rivnuts give you a good compromise....
You're right. I was thinking of self locking nut plates as well. These things
thanks guys so screws would be ok for iva?
Iva should be fine if all secure and pointy ends aren't contactable
I was thinking this sort of self tapper
http://uk.rs-online.com/web/p/self-tapping-self-drilling-thread-forming-screws/4831252/
When building my MK Indy I made an Aluminium plate for this area and riveted it to the chassis rails (also sealed it with some black sealant as well). No issues at SVA for me and it was easy to make further holes in for battery holding etc. I guess self-tapping screws would have worked, but I had the drill bits and rivets to hand so went with them - no regrets thereafter.
thanks for help more question soon lol