Try red gold or blue tungsten. I use gold.
I started practicing with my AHP Tig a few weeks ago. I went the the beginner videos on welding tips and tricks before I started and also signed up for his beginner TIG email series. I've been working on just manipulating the torch, no filler rod.
The machine is set to 100 amps, with 8 seconds of post flow (argon @ 20 CFM). All other knobs are turned fully to the left. I'm using 1/16" 2% lanthanated.
Please make any suggestions to my technique so I can fix it before it becomes a bad habit. The right bead was put down before the left one. They weren't done back to back, I ran beads on a couple other pieces in between. I feel like I'm struggling to find a comfortable position that allows my to support my arm but keeps some freedom of movement.
All of my tungstens end up with this "ring" near the tip after a couple of beads. I've tried; switching from cups to lenses, turning the gas up to 30 CFM, both #7 and #8, and using a 3/32 2% ceriated. I prep my practice material with a flap disc and acetone on paper towel until the towel comes off clean. I grind my tungstens using a drill and diamond wheel in my Dremel that is only used for tungstens. They all end up with this junk.
I think the hazy gray on my welds is oxidation, and maybe that's what's causing the tungsten to develop the "ring"? Is this a technique issue, or and equipment issue?
TIA.
Try red gold or blue tungsten. I use gold.
The gray on the welds means you're running too hot. Try either moving faster or turning down the amps.
100 amps is on the high end for a 1/16" tungsten; I'd try stepping up to a 3/32". If you overheat the tungsten, it starts disintegrating.
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I think the tungsten contamination can be fixed by increasing your freq. setting to a minimum of 60 HZ. Also play with the AC balance to increase cleaning action.
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I have seen the same thing on tungsten, though I don't remember what the cause was, or the last time I saw it.
I haven't had any issue with the 2% lanthanated on AC or DC, but Red (Thoriated) has kind of been king for steels. Honestly I can't tell much difference for what I do, between tungstens.
Are you dipping your tungsten? Maybe as an experiment try holding a slightly longer arc length and ensure that isn't the problem?
Your machine appears to be set right for steel, though I have no experience with AHP.
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If you look carefully at his machine settings picture you will see that he is welding on DC, not AC. Which would be correct for welding steel.
I've had that junk appear as well. Some say it is because of a tiny bit of moisture in the shielding gas, but high amperage for the tungsten also seems to be a culprit. Try a 3/32" 2%La tungsten and see if it still appears.
I have tried a 3/32" ceriated with the same result. With that tungsten, I was also using 100 amps on some thicker pieces of steel. When I bought my tank and gas, they were out of new tanks and sold me a used one. I wonder if there was some contamination in it?
I left the machine set at 100 because I was working on controlling with the pedal. I might be trying to add too many new things at once. I'll turn the machine down to 60 and see if that remedies the grey on the bead and the mushroom head on the tungsten.
The first few times I tried TIG, I was holding waaay too far off the metal and still ended up with this issue. It was on weldingweb that I learned the suggested distance should be the same as the diameter of the tungsten.Are you dipping your tungsten? Maybe as an experiment try holding a slightly longer arc length and ensure that isn't the problem?
which way/direction are you grinding your tungstens? you want the grind marks to go along the long axis of the tungsten, not across it. How thick is the material you are welding? 100 amps is likely not hot enough. TIG is unusual in that if you less amps, it causes you to take longer to form a puddle and you move along slower. This actually causes the metal to overheat. You really want to go to a larger diameter tungsten (3/32) and up your amps a bit. if you are running 1/8th material you will want to be around 120-130 amps at max on the dial, and control it from there with the foot pedal.
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My grinding setup is similar to this. I chuck up the tungsten in my drill and run it against the flat edge of the disc, sort of like a needle on a record, but at much more of an angle.
One common thing I'm picking up from all the responses is speed. I think I'm just not moving the torch fast enough. Is there a rule-of-thumb for torch speed, like so many inches in so many seconds?
I think maybe you are grinding your tungsten incorrectly. Are you pointing the tip at the spindle, or are you keeping the point parallel to the table? I usually do mine on a belt grinder. I chuck them up in a cordless drill and point it back in the direction of the belt.
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That's one of those things that come with experience because there are so many variables. The main one is heat input, but that is not just equal to amperage. Arc length, torch angle, total part size, local joint geometry all affect how much heat is being dumped into the whole piece and also in the nearby vicinity of the weld joint.