Tungsten sharpening

Arc weld · Sep 3, 2013

Are you using a 3/32" tungsten? How far is the tungsten sticking out past the nozzle? From your sample it looks the piece got real hot but the weld was too cold and/or you added way too much filler rod. TIG welds are usually slightly concave or flat and your's looks more like a cold MIG weld going too slow. One last thing, were you on straight polarity? The black tungsten may be from getting too hot. Lots of beginners do cut the rods in half until they get the hang of it. The long rod can make you shaky trying to feed it.

deereman75 · Sep 3, 2013

I have 1/16 tungsten, but I will try and get some bigger stuff soon.
The picture really made the weld look weird. I have it in front of me, and it is concave along the whole way, and has some undercut in places. For some reason my camera made it look totally different from what it is.
I think my main issue is that I am moving way too slow.

Any suggestions on settings for 1/8 lap welds? I was running about 85 amps.

I had got the 1/16 tungsten because that's what my miller weld calculator app on my phone said was the size I needed. I guess it might be a bit off....
Edit: I was running DCEN.

Shield Arc · Sep 3, 2013

I seem to remember when I ran Furu's Stickweld 250 it was off by about 10 or 15-amps from my V350-Pro. Don't get to caught up in numbers. Do what ever the weld / puddle requires! I see where a lot of rookies worry too much about exact numbers. You are better off to learn what the weld / puddle needs, and do that. Think of the numbers on the welder as just a reference. I've taken tests when you walk into the booth duct tape is over the gauges. First part of the test is to set the machine. If you're not within the manufacturer's limits, test over you go home right then and there!

deereman75 · Sep 3, 2013

I guess I was going way too cold. My miller app says 100-130.... It did seem to be going really slow....

I am going to try and get some 3/32 tungsten. Any recomendations on what type to get? I just grabbed thorinated because its the old stand by.

DaveOmak · Sep 3, 2013

I still use thoriated electrodes... I'm conscious of the health hazards.... no big deal.... Just don't breath the dust when sharpening..... Dave

k0ua · Sep 3, 2013

Either Ceriated or Lanthanated are good all around tungstens with no risk.

deereman75 · Sep 3, 2013

I have no worries about thorinated tungsten. As I said, I'm sure burning a 7018 or two will do more damage.

I just figured if something worked better, I would use it.
Any thoughts on trimix tungsten? Air liquide has them for $10 per pack less than thorinated cost me..... LOL

Furu · Sep 3, 2013

I am by far in no way an expert on welding let alone TIG. With the help that Shield Arc has supplied me and my very limited "experience" with scratch tig and my stickweld 250; I thought I would chime in. Some thoughts that have popped up as I have read this and things I have screwed up.
I have had some tungsten that have done what I think your photo shows and the point turns into a ball very quickly after you get an arc. Is your arc staying very stable is is it dancing and flaring out irregularly? I use 1.25 diopters for reading and stick welding but have to use 2.00 diopters for Tig. I know you have young eyes but thought I would mention it. I found that I was letting the tungsten get too close to the puddle. I pulled back ever so slightly and it made all the difference in the world.

If I remember correctly Shield Arc gave me a rule of thumb of whatever thickness use that as a starting point for how much amps. I am using 3/32". My "new" stickweld 250 runs closer to SA's V350 than it did when it was broke but I am using from 110-115 for 1/8 in (0.125) for outside corner welds and 115-120 for inside or fillets. I also quit being "cheap"/frugal and when I grind my ceriated 3/32 and found if I took just a little more off on the grind that the arc was more stable. The only thing I came up with was that there were still impurities in the tip of the tungsten from my previous screwup that had not gotten ground out. I also started "polishing" the tip post grind with about three or four longitudinal pulls with 400 grit cloth along the shaft toward the tip. I also practiced on fillets with no filler just straight fusion to see what the weld looked like all by itself.

deereman75 · Sep 3, 2013

I think I may have found part of my problem. I don't like my tig torch. It is a stupidly huge wp-17, and the cup is at a 75 degree angle, and very long, which I don't like..... I bet I would do a lot better with a far smaller torch, with a flex neck.
I might try and find a good deal on a small torch.
Also, can I run a water cooled torch by hooking it up to the garden hose? Or do with have to build a water cooler?