First tig welds

[pondy]

Had a go at some tig today, I have a very basic set up comprised of an r tech 140mma and a cheap wp17 torch, probably not the best way to get started but all my budget can allow. I need to get a thick plate to do a pad of beads but couldn't wait and had a go on some scrap today, running before I can walk as I ran a joint, I need a lot more practice just running beads then getting the feel for adding filler Before I tackle joints. Turned out a lot better than I had expected, I do have craters at the ends of the welds due to breaking the arc and loosing gas coverage, I have a lump of copper I plan to use to get around that.

Some have brown soot around them, is this due to low gas flow? Had it around 5 lpm then turned it to 10lpm and it seems to have gone

 

[Richard.]

The fillet joint looks really good for your first attempts.
The brown soot isn't surprising. Could be gas flow, could be arc length, given the process it could be where you have pulled away to end the bead but been a little slow at doing so and extended the arc length allowing oxidation or it could be down to mill scale on the plate. 10lpm is high, too high in fact so I would suggest getting a peashooter for the ceramic and set it up there at 6-8lpm.

 

[Brad93]

At 10lpm with a standard collet body I would imagine you could even be creating eddy currents that pull in air, on steel I run about 4lpm through a size 5 cup.