Using electrical conduit for roof rack

[Mark_BC]

I want to make a full length low profile roof rack. I bought some cold rolled square steel tubing from Metal Supermarket which is nice strong stuff and good to weld, but it has been sitting in the garage for a few months and man does it ever rust with the slightest bit of moisture. I don't trust using it on the rack. Any nick in the paint is going to cause major rusting.

Some people make racks out of electrical conduit. It is galvanized and won't rust. They say it is toxic to weld but I'd just grind off the galvanizing where I weld. But it is pretty thin walled and not very strong. However I'd only plan to use it to lay down directly on the existing frame rails, with tabs welded on the sides to bolt onto the sliding nut inserts int he rack. So it might not be so much of a problem that it isn't super strong. Since it would be continuously supported by the existing frame rails. If I tried that with the metal Supermarket tubing it would for sure rub, rust and be impossible to touch up.

For cross bars I'd use 1" steel tubing like I mentioned before but because that would be elevated off the roof rack rails, any paint chipping would be easy to access and fix. These I would weld onto the EMT conduit running front to back.

Any other thoughts on using EMT for roof racks? Or other tubing that is available, cheap, strong and doesn't rust so bad?

 

[Mark_BC]

Maybe using this black pipe from Home Depot. It's fairly heavy and I'm not sure how I'd do the bends.

Mueller Streamline 3/4 in. x 10 ft. Black Steel Pipe-584-1200HC - The Home Depot

 

[Roamed YT]

Cheap, Strong, Light & Rust-resistant. Pick any three.

Angle & Square isn't too bad but yeah, you do need to protect it properly. If you were willing to spend, I'd suggest going aluminum. Solves the strength, weight and corrosion issues at the cost of well, cost.

 

[theesotericone]

1" PVC. Light and rust proof.

 

[Mark_BC]

1" PVC. Light and rust proof.

Actually that might work for the frame rails, use some Sched. 80 which is pretty strong, fairly easy to bend with heat. Then how to make the cross members that attach to that?

 

[Mark_BC]

Cheap, Strong, Light & Rust-resistant. Pick any three.

Angle & Square isn't too bad but yeah, you do need to protect it properly. If you were willing to spend, I'd suggest going aluminum. Solves the strength, weight and corrosion issues at the cost of well, cost.

My welder does aluminum which I have never welded, maybe worth a try.

 

[theesotericone]

Actually that might work for the frame rails, use some Sched. 80 which is pretty strong, fairly easy to bend with heat. Then how to make the cross members that attach to that?

You could build everything with T's and 90's and cross sockets(4 ways). The longer the pieces the more prone to bending they would be. If you used t's along the rail and cross sockets every 12" or so for the cross members I bet it would be pretty damn strong and not flex much.

 

[Mark_BC]

You could build everything with T's and 90's and cross sockets(4 ways). The longer the pieces the more prone to bending they would be. If you used t's along the rail and cross sockets every 12" or so for the cross members I bet it would be pretty damn strong and not flex much.

And you saw the roof rack that slid off the 4runner totalled in Oregon today?? LOL. Although that was the nutserts that slid, not the roof rack itself falling apart.

 

[96RedRunner]

My welder does aluminum which I have never welded, maybe worth a try.

.

Be prepared for a learning curve with aluminum, it can be a pita. It flows different than steel when molten. But it is worth the trouble.

 

[96RedRunner]

EMT works very well, I built mine using 1/2" & 3/4" doesn't weigh but 30#'s, is a bit longer than the rails. I tote 3 55# kayaks all the time doing interstate speed.
Being toxic is a bit over stated, don't weld it in a small enclosed area, use a fan to pull fumes away your good to go. Have been working with galvanized steel a long long time.

 

[rbgerrish]

And you saw the roof rack that slid off the 4runner totalled in Oregon today?? LOL. Although that was the nutserts that slid, not the roof rack itself falling apart.

That was mine! I had some extra conduit after a house project and needed a roof rack for an event I was attending. I ground the galvanizing off before welding, and still wore a proper respirator. I painted the whole thing black and bolted a piece of plywood to the top. It was quite strong, I could stand on it easily. I was going to remake it out of regular DOM 1" tube...

 

[rbgerrish]

One more if it done

 

[beer-toe]

One more if it done

how did you attach the inserts the rack rail? was it bolted or just slide into place? [MENTION=123612]rbgerrish[/MENTION]

 

[Mauzer]

Plenty of people build roof racks with EMT, you can use muriatic acid to remove the galvanized coating.

 

[MandAtaco]

[MENTION=73515]ajonesnv[/MENTION] built a couple really nice racks out of EMT before switching to mild steel. They all seemed plenty strong to me. Easy to bend with a standard EMT bender too. As stated above, biggest thing is welding the galvanizing.

I just finished a rack using 1" steel, bought 4 20' sticks for around 45 bucks I think. Stuff is pretty cheap if you don't want to deal with the galvanized EMT.

 

[rbgerrish]

how did you attach the inserts the rack rail? was it bolted or just slide into place? [MENTION=123612]rbgerrish[/MENTION]

I just slid them into place. The tension from securing all the mounts to the rack flexed it a bit to keep it from going anywhere, and the front and rear stops were on. (barring a 45mph head on collision!)

There was room to drill holes to bolt them down.

 

[turbo8]

The galvanized steel will rust where you welded it together.
Get the mild steel rack powder coated, it will be pretty hard to chip the paint off.
Your welder should be able to weld stainless steel too.

 

[96RedRunner]

When working with galvanized steel you can use a product (cold galvanized coating). Comes in spray can to keep it from rusting, use it like a self etching primer, then top coat. All steel will rust, even with powder coating.