More TIGing Practice from Brad...

[blasphemy000]

Thank you, all of you guys, it's very encouraging. I'm learning more every time I use it so I'm happy so far. I'm mainly practicing holding proper arc length and consistently feeding wire at the same time. I'm slowly getting the hang of it. Like I said, I've got about an hour total torch time. For the type of machine I'm using, and the homemade torch, it works surprisingly well. It is scratch start though, so that's kind of a pain. I did learn that 2% Lanthanated holds a blunted point better than 2% Thoriated, with the scratch start anyhow. Can't wait until I can afford a 250EX though cause I want to try my hand at some aluminum.

My power source is a 90A Chrysler alternator strapped to a 220v 1.5HP Westinghouse motor from my air compressor. I'm powering the field with a battery charger with a rheostat to control the OUTPUT power from the battery charger. My foot pedal is a Phase-Angle controller from a sewing machine plugged into the wall and controlling the INPUT power to the battery charger. I set the max current with the rheostat and then use the foot pedal to vary from 0-Max. I just recently added a micro-switch to the foot pedal and a gas solenoid to control my argon. The brass valve I had mounted to the torch was heavy and made the torch really cumbersome. Also, on my original torch design, the head was 90* to the handle so I couldn't hold it properly, with this new redesign and the angled head, I can hold the torch properly and it's helped quite a lot. I really can't wait until I have a proper machine to use. With a few tanks of gas worth of practice, I'm sure I can be really good at this. If you want to see pictures of my machine/setup, I have a thread in the introduction section from a while back.

@Tritium: I've thought of that. The alternator has taps just inside the case into each of the 3 phases. Unfortunately I'd only be able to feed a single phase into the torch because with 3-phase power, the phases overlap each other. With all 3-phases combined and rectified I have a MAX of 90A, so with a single phase I would only be able to get a max of 30A or less, so I would only be able to weld very thin aluminum, if it would even hold an arc w/o HF. Because of this I've decided against trying to wire an external tap into AC output of one of the phases.