[#90-GTSC]

My enclosed race trailer has a steel skeleton, 16" on center, with an aluminum skin that was attached by self-tapping sheet metal screws. The screws use a square (Robertson) bit (four points) and have an eight point "female" on the oval head of the screw.

I've looked and looked and cannot find screws like this.

My problem is that it appears these are galvanized ... but some (not all) the heads rust. I'd like to replace the rusted heads with fresh identical screws. Ideally I'd like to replace them with stainless steel screws with the same head design.

Up to now I've been using stainless steel Phillips head sheet metal screws, which appear to get the job done, but don't match very well. And of course there is the issue of the Phillips bit wanting to cam out of the screw head and stripping it. My preference is a square Robertson head (four points), or the eight point into which the Robertson goes fine, or a hex, or a Torx.

Anyone know of a source for that? Especially in stainless steel.

Every once in a while I toy with replacing all the screws with pop rivets. The trailer is red, and I should be able to find pop rivets the racers use with a red aluminum head. But are those strong enough? I think they are aluminum. I'm a little concerned that if the hole is now bigger than the rivet shank, then moisture (rain/snow) might get by the head and into the steel skeleton and start to corrode it from the inside out.

Has anyone has experience with this? Has anyone riveted the sides of their T/C's using rivets like this?

Thanks for the help.

Dick