TIG Welding – First Results
Well to be honest these are not my first results but the first ones that I was not too ashamed to publish.
Here’s the welder and the thermalite and slab of steel I’ve been using as a mini welding table. You can see my new vent in the background. The disposable gas is a bit expensive but I’ve not yet sourced a North London supplier of Argon in larger bottles who does not require rental.
I started on some 3mm mild steel , which I cleaned up using a angle grinder and a flap disk. First experimenting with getting a puddle and practicing adding the filler rod (left) and then tacking and various pieces, one of the later results (right). I’ve still to do a strength test on these, my previous attempt just snapped right in half with a simple tap of the hammer. At this thickness I found 80-85A seemed to work about right, I expect as I get quicker I’ll need to turn up the settings.
After three or four goes on 3mm steel I though I’d try some 1mm. I set the current down to 45A and successfully joined the sheet. You’ll see I’ve a bit of a melt through at the edges but that should go with practice, the trick is not to stop when you get to the end.
Finally I gave a go with a T joint, I just tacked the re-bar either side to a small offcut of square steel bar.
Feedback from the welding forum:
“The blue/grey is fairly normal, it’s surface oxidation colours depend on the temp of the metal when the gas shield moves away
You really want a root gap for 3mm steel, can use the filler wire to set the gap. Larger coupons would make life easier. The 1mm sheet, really need some 1mm filler (or straighten some 0.8mm MIG wire) and no root gap for that sort of stuff- 1.6mm filler takes more heat than the base metal making life a fair bit more difficult
Looks to me like your arc length is too long. Keep it tight, less than 3mm preferably no longer than the tungstens diameter. Longer arc length and the heat fans out so you tend to get a weld that has signs of too much heat while also looking cold”