Strike a balance between visually appealing and structurally sound TIG welds, even on social media

I’ve noticed a trend on social media lately where welders post photos of their oversized aluminum beads with the description of “stacking dimes” or “walking the cup” to denote exceptional welding profiles. While I admit they are visually appealing, structurally they make me nervous.

Usually an aluminum TIG weld needs to be cosmetically appealing and structurally sound enough to hold a liquid or a gas. This means precise penetration is of the utmost importance. It needs to be leakproof.

Just how leakproof?

I have welded a product that needed to be so tight that not even a helium atom could sneak out. This product also allowed just the tiniest amount of melt-through. The entire length of each weld was then tested using a mass spectrometer leak detector, which we referred to as Veeco because that is the machine’s brand name. But I digress. This device located and measured the size of a leak either by vacuum testing (inside out) or pressure testing (outside in).

If a leak was detected, we had to remove the welded material and start over, which was incredibly labor-intensive and time-consuming. Often a concave weld was used for the first pass followed up with a convex weld pass for aesthetics. Sometimes that convex pass was completely milled flush so you wouldn’t even know it was there.

I guess what I’m trying to say is, aluminum welds are much more than a pretty bead. An important thing to remember is that aluminum is susceptible to bulging with excessive heat input, so make sure what is on the back or inside isn’t being touched with excessive weld, potentially ruining components. For example, I once made a bulging aluminum weld on a medical laser and accidentally touched a $9,000 component, rendering the entire laser useless and unsalvageable. You might say I learned the hard way about the detrimental effects of excessive heat input.

For all of you aluminum welders out there, keep posting your work on social media and playing around with bead design. You are doing beautiful work and getting others interested in our industry.

But once you’re out in the field, always check your tolerances before deciding on how big your bead should be. If it’s structural, get the tightest-penetrating weld in there. Then post a picture of it because that’s the weld I want to see.