I have an old Uhaul that I'm turning into an rv. I'm putting the exterior unit of a ductless mini split AC on the "mother's attic" portion of the truck box directly above the windshield.

They make a wall bracket for hanging these but I don't think it's designed for hitting pot holes at 70 mph. So I plan to make my own bracket. I'll also be framing for a cover vent and fairing for protection and streamlining.

The weight needs to be kept down so I'm thinking of using 1 inch aluminum square tubing with a 1/8 inch wall to make two L-brackets. I'd be using an DC tig welder with Alumiweld brazing rod. The rod claims a tensile strength of 40,000 PSI.

The charged AC unit weight is 85 lb and the center of mass will be about a foot from the wall.

Does this sound like it would hold up? I really don't want this thing crashing down into my lap.

  • 1
    $\begingroup$ Brace it, that’s why many brackets have a triangle involved. $\endgroup$
    – Solar Mike
    Jul 2, 2021 at 4:09
  • $\begingroup$ Thanks Mike, the diagonal piece would have to be short to fit between the upright bracket leg and the foot ot th AC. About 4.25 inches. But i still don't know how much stress hitting a bump would create or if the aluminum will hold up. $\endgroup$ Jul 3, 2021 at 10:12

1 Answer 1


Short answer, no. At least not by me. I thought I had seen a video using a tig torch to braze the Alumiweld but couldn't find it again so I just used MAP gas instead. I'd get one side brazed, flip it to do the other side. But then the 1st side remelted and things fell apart. Then I found a promising method on video. Watch "Welding Square Aluminum Tubing with HTS-735-11" on YouTube https://youtu.be/PetfKFWGMUo I was able to make an L bracket, but it couldn't support my weight. I bought steal square tubing today. It's heavier than I'd like, but it will TIG nice and strong.


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.

Not the answer you're looking for? Browse other questions tagged or ask your own question.