A fairly new TIG welder asked Kevin about triangular wave welding.

What do you use it for? Why do you need it? Should he buy this machine that has it or get that machine that doesn’t?

Triangular wave works with AC, so that means when you’re TIG welding aluminum, magnesium and other exotic metals. Mostly, though, it’s for aluminum.

Because of the short, short duration of the spike of the wave, you are able to weld very thin metals. It also helps with outside corners. Using triangular wave helps control the heat and therefore blow through. It also really, really helps when you’re out of position doing something weird.

Kevin is going to show the difference between the old-fashioned sine wave that was on transformer machines, and then he’s going to cool the metal down so it’s starting from cold again, and weld a section using triangular wave – without changing any the other settings.

OK: 16 gauge aluminum, outside joint. Let’s make some sparks!

Kevin is using the Everlast PowerTIG 255EXT. He shows how to set the machine on sine wave and on triangular wave. Other than that, he isn’t changing any other settings. He has the welder set at 80 amps, the AC frequency at 60 hertz, and the AC balance at 35 percent.

He puts on his safety gear and first tacks then welds a section set at sine wave. Next he tacks and welds a section using triangular wave.

The side Kevin welded with sine wave has a small shadow of AC balance cleaning around the weld. The weld looks nice. The triangular wave side has a much bigger area of cleaning, and that’s without changing any other settings on the machine. The triangular also has a much tighter bead.

On the back of the metal you can see some discoloration on the inside of the joint on the sine wave side where it was trying to burn through a little.

On the triangular wave side there’s just barely any hint of discoloration. It’s a much cooler weld. You could actually increase the amperage on triangular wave side. You get a little more penetration with triangular wave, but it’s colder, which is one reason it helps prevent burn through with the thin metals.

That’s why Kevin always reaches for the triangular wave button when he’s welding on the outside edge of some 16 gauge, 18 gauge, 20 gauge or thin metal. Triangular wave will also be good for those who like to weld soda cans together.

Kevin hopes that answers the viewer’s question. Before you go, you might want to hang around for another moment to see him not quite see eye to eye at the beginning of a video ….

See this video now ….