sheet metal fastener

[monkeydelmagico]

Need some brain power y'all. Help a fellow gear head out.

I need to bolt to sheet metal without being able to get behind/to the back of the sheet metal. Kind of like fastening into drywall but hope there is something a little more robust than a plastic insert. Sheet metal screws alone are out, not strong enough. Rivets and tack welding are out, needs to be removable.


Anyone got suggestions?

 

[Greenman]

Threadserts are your answer.

http://www.amazon.com/Thread-Setter...TF8&qid=1400197108&sr=1-2&keywords=threadsert

 

[boomerang]

http://www.enfasco.com/atlas-fasteners.php

I've used these before and they're pretty slick. Upper left, Half-Hex Shank Low-Profile Head. Click to check the catalog. The thinnest sheet metal they will grip is .020.

You drill a hole that is an interference fit for the hex portion. The far end of the fastener is threaded internally. You will thread into that and actually collapse the fastener. It will grip the thickness of the metal and the hex is added insurance against it spinning. The catalog shows them before and after installation.

 

[boomerang]

Is the metal beefy enough to weld a nut onto the backside? Drill a hole and tack a nut in place would be your least expensive option. If it's thin, you're obviously going to distort the hell out of it.

 

[phucheneh]

It sounds like what he's attaching to is already installed and inaccessible from behind. Perhaps not.

But if so, that removes the option for any kind of threaded fastener. Heck, if he could get back there, nuts with the little 'teeth' on the bottom (unsure of technical name) or just a star washer beneath them would be doable. You just pull on the bolt a bit as you tighten/loosen so that the nut and/or washer gets a bite.

Really sounds like a rivet situation to me. If you just want it to be ABLE to be removed, as opposed to KNOWING you're going to need to constantly remove it, rivets still make sense. Especially if aluminum ones will be strong enough (they are super easy to pop the heads off of with a half-decent drill bit).

Hell, there are even 'plastic rivets' a.k.a. 'push pins' out there that are pretty damned strong. Strong enough that I've bent many a piece of sheetmetal trying to remove damaged/stuck ones.

 

[monkeydelmagico]

you guys are the best. I didn't even know what they were called but had an idea what I was looking for. They go by alot of different names, well nut, rivet nut, threaded insert, etc. Found something similar to the atlas rivnut at the local fastenal. I think it will work perfect. Thank you again.

 

[Fenixgoon]

pop rivets would also work, IIRC