Cory M

They aren't Allen, they aren't Torx, they certainly aren't Phillips. Is it Metric, standard? Who knows...

Why do so many trailer companies use these oddball star pattern fasteners to secure the siding, interior, and other parts? It's a weird size and you can't find bits for it at a normal hardware store. I've got literally hundreds of bits, including a complete kit of specialty drivers, and none of them fit. If you try to force a similar bit in there it will strip the head of the screw. Why do trailer companies do this? Is it so you have to take it into the shop for service when things loosen up? It makes doing simple repairs and outfitting the trailer with racks and gear such a pain. I end up drilling a bunch of new holes in the walls instead of just reusing the existing holes.

Any of the trailer company reps that hang out on this site have a logical explanation for this?

Trailers of the East Coast

If you're talking about the screws on the sidewall, they use a standard #4 square drive bit, they're just designed so the bit can engage in twice as many orientations. It's a cheap and common design (zinc plated usually, self drilling/self tapping) that's easy for mass production to mindlessly bang in without a ton of hands-on with the fastener. A lot of them actually have strip-fed screw guns now for speed.

ATC has gotten away from screwed exteriors entirely and gone to screwless standard -- Cargo Mate (as well as other Forest River brands) have abandoned them in favor of stainless T6 Torx screws.

I personally can't stand them but they're so prevalent in the industry that it's a necessary evil to deal with.

- Matt

Cory M

Last few trailers I've worked on had a star pattern with 8 or 10 points, versus the torx with 6 points. I wish they were square.

Trailers of the East Coast

If it is the 8 point "star" it is known as a double square drive, and a #4 square bit is what you use to install and remove them.

Looks like this:

Cory M

Cool. I'll give that a try. Should work better than jamming a torx in there and cursing. Thanks!

Trailers of the East Coast

No worries! They actually make a bit for them but the #4 square works so well that even the manufacturers that build the trailers use the square bit instead of the goofy 8-point one. Never had an issue.

- Matt

jlanka

Yup thats what my CH305 has

LuigiVampa

I have been hand tightening the same three screws that keep working themselves out because I could not figure out what bit, amongst the tons of bits I have, would fit this. Never tried square!