After buying my first TIG machine, I had set to teaching myself anything about it I could... many of my favorite useful tidbits have come from this group, in fact. ButI thought it best to still take a class, and after some research found only one place in the nearby area (a community college) that offered a TIG course. So I took it. A few classes have passed, and here's things I have seen/learned in the class that just don't sit right with me and what I had learned thus far:
- There's lots of tungsten types available, but all you ever need is the 2% thoriated kind... all AC aluminum welding in class is being done with them, in fact.
- You need to grind a point on a tungsten, but there's no special procedure... just whack it a few times with any old grinder and make it kind of sharp.
- Argon flow rate? Just whatever.
- Yeah, stainless just gets all black like that when you weld it. Just grind it if you don't like how it looks.
I'm wondering what other bits of knowledge will arrive. Granted, it might just be that the instructor is letting us play around with the equipment to get a feel for the process first, and I hope that's the case, but we'll see. The first day in the welding lab brought lots of interesting demonstrations on grinding tungsten (I saw one that was so badly balled up it looked like it had a bee sting on it, and the student was sharpening the ball into a gigantic tear drop shape) and eye protection ("Hey, the arc's really not all that bright..."). And I guess the little spikes that appear on the thoriated tungstens after a few minutes of welding on AC just means it's time to go re-grind.
In the meantime, I'm perfectly happy to keep using my zirconated tungstens with the nice concentric points ground in them with the grind marks running lengthwise exactly the way I've learned from listening to the knowledgable and experienced folks on this group, and people have been wondering why I hardly ever need to regrind my tungstens and why my beads are so much more uniform....
Bryan