[RichardH]

I had an interesting experience today... The arc kept climbing the tungsten like a Jacob's Ladder, deep into the cup, nearly to the gas lens - completely skipping past the tungsten for over an inch and staying like that. Long enough I nearly pulled out my cellphone to get a pic.

Working 10-20A pulsed with 0.040 tungsten in a CK Gas Saver, #8 Pyrex cup, 10 CFH, 1/4" stick out. I'm wondering if the gas was too low, or a breeze could cause this effect. Or poor contact with the tungsten inside the collet? Good chance this happened shortly after I contaminated the tip.

[Braehill]

Richard,
Maybe it happens more often and goes unnoticed because we don't see up in the cup like you can with Pyrex.

My only thought as to an explanation would be that maybe your tungsten is split lengthwise and being .040 it is hard to pick that up, but you can hold both ends with pliers and twist it in opposite directions and see if it splinters. Don't go crazy as it is only .040 and not very strong.

Len

[Otto Nobedder]

Impurities/moisture in the gas can cause this also, most noticeable at low amps.

Is your bottle getting low (under #500), or did you recently switch to a "fresh" bottle?

Len's idea is also valid.

I assume the weld is not new to you, only the climbing arc. What else is new or different? Any fresh torch parts? Refill the water cooler?

Steve S

[Bill Beauregard]

I haven't seen it at higher amperage, I tried the soda can trick first with the Diversion 180, instant burn through. Then the Dialarc, starting low I kept having to turn it up. I think my dial must be very inaccurate, I made it to 35 amps to get hot enough to melt. At lower current it was near impossible to keep the arc at the end of the tungsten. I believe at low current settings I was seeing only the High Freq. It seemed to produce no heat, it wanted to arc off the side of the tungsten 3/8" from the tip to the shoulder of the cans. Maybe in my case a smaller tungsten would have helped.

[RichardH]

Impurities/moisture in the gas can cause this also, most noticeable at low amps.

Is your bottle getting low (under #500), or did you recently switch to a "fresh" bottle?

Len's idea is also valid.

I assume the weld is not new to you, only the climbing arc. What else is new or different? Any fresh torch parts? Refill the water cooler?

Steve S

Hi, Steve.

Thanks for the suggestions. No, the bottle has about 1200# in it. I put a new hose on it recently, but it holds pressure overnight with almost zero loss, so not sucking air (at least not up to the welder).

It's a new torch - CK FlexLoc w/ gas saver. So a lot of parts have changed there. But the problem's not chronic, and odds are high that it's due to dipping the tungsten. It's the first time I've used a Pyrex cup, so also might not have had a good seal at the torch.

Mostly, it was odd and briefly consistent, so I was curious if it was a common problem. Not an ongoing problem, so no sweat.

Cheers,
Richard

[Markus]

Ramp up time helps on some machines. Just add a second or two on start ramp and problem disappears.

[NITROTRIP]

Hello All,
I have been Heli-Arc, OOPS< TIG welding since 1976 and it still amazes me what
I forget to do and then fight a problem.
I have only welded with Inverter TIG machines for a few years, before that just
transformer machines. What I have noticed is the inverters are a lot more
sensitive to the most basic things at low amperage than the transformers are.
I just tested this yesterday using the same argon bottle on both machines at very
low AC amperage on 2machines. One is a Miller A B/P 330 1961 vintage, the other
is a Everlast Power TIG 250 that is the newest generation, 5 months old.
The A B/P has a Original 25 foot TEC 350 amp torch, the Everlast has a CK 25foot
series 20 torch. Both water cooled.

Here is what I found.
Tested this on pop can bottom to bottom welds as you know very thin and weld
in a deep low amp valley.
Both machines with torch cables laid out with no crossovers or loops.
No problem with both machines, 35amp max with pedel
I then put 5, 18 inch coils in both torch cables at the machine.
The A B/P I could still weld the can but it was a fight with some arc wander.
But could still do it just messy.
The same loops with the inverter machine and it was impossible due to arc wander
and the arc climbing the tungsten, no new fangled magic setting worked or even
helped in any way.
Then did test again with 150 amp max and 90deg fillet on 3/16 aluminum.
Wander was still there but now where near as bad, and could complete the weld
without much problem. The inverter you could increase the hz and tighten up
the arc and no more wandering. Uncoil the torch cables and it was like you
hit both machines with a magic wand.

Something to think about, that simple could cause problems everywhere.
Us old guy's forget, new guy's don't know, same problem.

Take Care,
RICK

[RichardH]

Hi, Rick.

That's a really interesting observation! Thanks for posting it.

I'll expand on your thinking... since the work clamp completes the circuit, odd results could be expected with coils in its cable too. The only difference being that the work clamp is usually tied to a very large mass (electrically-speaking) like the welding table, which may reduce the effect of coils in its cable.

Cheers,
Richard