Thread: Fixing to RHS posts

Can you get a nut and washer where you need it to go? Yeah 4mm a little on the thin side for tapping in the application you have suggested. If it's steel, why not just weld?
Regards
Robbo

4mm thick is perfectly adequate for tapping a small diameter thread in, say 5 to 6mm. However I'd say it would be loads easier to use self drilling screws, AKA Tek screws, with a fine thread.

Example

I think you'd be in for a world of hurt if you wanted to weld it. Especially with aluminium and powder coated material.

I think you'd find that most people would use one of these:



And lots of these:

Either of Bee utey's suggestions. However the best suggestion is things called "rivnuts" (or other proprietary names), especially if you may want to remove them or replace them in the future. With these you drill a larger hole and insert a special nut that uses a special tool to expand the nut and rivet it to the post. See any specialist fastener shop, possibly a good hardware shop. Tapping into 4mm is possible, and probably strong enough. I have a variety of fittings attached to my verandah posts of similar material using both of bee utey's methods. If you use self tapping and drilling screws, get the fine thread ones for preference.

John

I'd be looking towards fixing a "U" section to the posts with something similar to Beeuty's link (same as Buildex series 500), don't try to use a coarse thread on 4mm steel as you'll snap more screws than you'll get in. Get your first slat in place and secure it from the back with a pop rivet at either end and from there on it's only a matter of placing a small piece of shim (Capral should be able to sort you out some plastic shims from 1 to 10mm thick that window installers use) inside the channel for the next slat to sit on and repeat the process. You could stick with angle on your posts but the screws and end gaps of your slats will be visible from the inside and the slat fixings will be visible from the outside and that would be Fnugly.

Self tappers or pop rivets ...................

We've recently done exactly this at my young bloke's place. We attached an aluminium frame to the steel posts of his car port, and then shadecloth over the aluminium frame.

He drilled the holes - I used my compressed air powered rivet gun. Took all of about 5 minutes to attach the entire framework.

Originally Posted by robbotd5

If it's steel, why not just weld?

I can still see my TAFE teacher back 37 years ago shaking his head at my welding. This project is meant to look good.......not something chucked together by a desk jockey with no clue

Originally Posted by BMKal

Self tappers or pop rivets ...................

In the future when I get around to enclosing my carport this is how I plan on doing it. Most likely self tappers as I only have a hand rivet gun.