My last post leads me to yet another question! (I'm full of 'em, ain't I?) Thanks for all the answers so far. There's obviously a lot to know about this topic, and I'm just scratching the surface at this point (pun intended!)...

What are the start methods for TIG (I'm going to make my best guess, so correct me and/or add detail):

1) Scratch start: most primitive, drag the tungsten electrode across the workpiece and lift it, like with stick welding.

2) Touch start/lift start: I'd assume there's some circuitry involved here that determines when you've short-circuited by touching the workpiece then lifting the electrode off the work piece?

3) High frequency start: to my understanding, the power source superimposes a high-frequency AC voltage on top of the AC or DC current at the electrode to help the arc jump the gap, then shuts this off, leaving with you with low-frequency AC or plain DC (depending on what you've set the machine to, etc.)

4) High voltage start: Rather than a high frequency voltage, the power supply superimposes a very high voltage on top of the AC or DC current at the electrode to help the arc jump the gap.

5) 2-stage non-HF/4-stage HF: See my previous post about the ESAB 161 AC/DC. I have no idea here (unless you push a button on the torch 2 times or 4 times to switch from a start arc to weld arc, or something along those lines). I'm hoping someone can explain this one.

This covers the arc start methods, right? Which ones are also used to maintain the arc as well as start it?

Regards,
Dave