Board logo

Fixing on to powdercoat?
Slimy38 - 23/7/13 at 08:17 AM

A quick question regarding powdercoated chassis. On my travels on other car forums, there have been numerous reports of people's wheels being powdercoated, then torqued up on the car followed by a detached (or at least wobbly) wheel. The recommendation has been to at least cut the powdercoat away from the bolt holes, so the bolts can get a proper seating.

Does the same apply to powdercoated chassis, or isn't it as critical? I'm guessing the nylocs prevent complete loss of fixing (whereas a wheel bolt is just torque). I wouldn't want to get a nice new chassis and then have to remove the powdercoat just to get a proper fixing.

Then again, how does powdercoat behave when a bolt is fixed to it, does it stay in place or does it simply twist off as the nut is tightened?

nick205 - 23/7/13 at 08:35 AM

If you tighten a nut directly onto it you will damage it the same as paint, best to use a washer. The downside to powder coat is the difficulty of repairing chips and scratches, much easier with a painted finish.

Slimy38 - 23/7/13 at 08:40 AM

quote:
Originally posted by nick205
If you tighten a nut directly onto it you will damage it the same as paint, best to use a washer. The downside to powder coat is the difficulty of repairing chips and scratches, much easier with a painted finish.


I would use a washer anyway, but I've sometimes found even the washer will turn on the paint and damage it?

nick205 - 23/7/13 at 10:01 AM

Same risk with powder coat, particularly if you've drilled the hole after it's been coated.

jacko - 23/7/13 at 01:03 PM

The thing with wheels is the brakes heat the coating / paint that melts the paint and makes the nuts loose
Where i work we never paint the backs of wheels or where the nuts fit for this reason
Jacko

Slimy38 - 23/7/13 at 02:45 PM

quote:
Originally posted by jacko
The thing with wheels is the brakes heat the coating / paint that melts the paint and makes the nuts loose
Where i work we never paint the backs of wheels or where the nuts fit for this reason
Jacko


Aha, so it's the paint going soft that can allow the nuts to loosen. So I guess that won't really apply to a chassis? (Or at least I'd hope a chassis wouldn't get as hot as a wheel!)