I’ve been trying to read up as much as possible about TIG welding aluminum, and some of the issues that are encountered. From what I’ve seen, there seems to be a general fear of doing it, for a few different reasons:
- It behaves differently than welding steel.
- The welding equipment can be quite a bit more expensive.
- It’s not difficult to make a joint that cracks and breaks.
- Aluminum itself may fail earlier than a similar part made of steel.
- It takes a bit more coordination than something like MIG welding.
Given how many vehicles are now being made out of the stuff (and how many more will be made from it in the future), I’d think that knowing how to weld it would be a very handy skill to have. That, and I’ve got a few personal projects that would involve fastening together some bits of aluminum.
So far, my only experience with it is from a few years ago in a welding lesson I got from an uncle. We cut and re-welded a section of aluminum irrigation pipe. I’m hoping to get a few more lessons in the near future, and maybe eventually purchase my own equipment.
To counteract the above points:
- Yes, aluminum behaves differently than steel. The puddle flows differently. From what I’ve read, if a person starts with aluminum, you don’t really have to un-learn what you’ve done with steel.
- Yes, the equipment is more expensive, but there seems to be some pretty decent lower-cost options out there, like this guy: http://www.everlastwelders.ca/tigwelders/pow…
- To prevent cracking/breaking joints, it seems like there’s a few things that are critical: surface prep (removing as much aluminum oxide as possible using a stainless steel brush, then rubbing down with acetone or alcohol), using the right tungsten (100% tungsten, not thoriated, if using alternating current), using the right gas (100% argon), slowly tapering off the arc when stopping a joint, etc.
- Aluminum fatigue is a real thing - just ask anyone who works with airplanes. Part of avoiding this comes down to the design of whatever it is you are making, and knowing that it isn’t going to last forever. Not everything can or should be made from aluminum.
- Yes, it takes more coordination, and thus, is going to take a lot more practice. Having also tried stick and MIG welding, I can say that MIG seems by far the easiest.
So Oppo, I’m wondering - does it sound like I’m about on track, or am I completely out to lunch? Am I completely underestimating how difficult it is to work with aluminum?