Welding Tips and Tricks

Hello Everyone,

I have used an old Miller TIG welder for years. I just replaced it with a new UNIMIG 200 AC/DC TIG. The old Miller had next to no settings. The UNIMIG has knobs everywhere. I am having trouble with the tip of the tungsten. I am unsure what is wrong. With the old Miller I got a round ball end when I used too many amps. This has weird little balls on the tip.

Ray.

What are you welding steel or al? What is your tungsten? How are you preping your tungsten? What’s your base metal condition? I might not be able to answer your question but put some more info out there and someone will help you out!

That tungsten is fractured badly. If you were using a 100% pure tungsten (green) on your older transformer, and now have switched over to an inverter, its better to use a 2% lanthanated (lt blue) tungsten. But your tungsten prep needs some attention.

A good method for AC welding with a Blue or Green tungsten, is to turn the balance down to 30-50%, hold the tungsten square to a piece of scrap aluminum, then ramp the pedal up slowly using ~150 amps. This will but a clean, symmetrical, small ball on the end of your tungsten (assuming you've prepped the end properly). Then return your balance to ~70% and weld away.

Don't "snap" or "clip" your tungsten. It will cause micro fractures. Grind them in half on the edge of your bench grinder wheel. Then make sure you grind the tip inline with the wheel to put a taper on it. For AC, I blunt the end very slightly then ball it.

*** You didn't indicate much information, so if this is all known to you, my apologies.