[domino]

Hello all. I am another TIG newb and am trying to troubleshoot a problem I have recently had while welding some .125" wall mild steel tubing.

I am using an inverter based machine with the following settings:

0.1 preflow
20A hotstart
125A peak current
50A backround current
60% Pulse width
1Hz
6 sec post flow

I am using the following set-up:

3/32" 2% thoriated tungsten (about 3/8" stickout)
20 CFH Argon
#5 cup

I am welding mild steel to mild steel, new material. I cleaned with Lacquer thinner prior to welding to degrease. What is happening is that as I increase amperage with the pedal when I start getting near full amperage the tungsten will flash a bright light which overpowers the helmet and basically blinds me. There is no evidence of damage/contamination to the tungsten. I initially started welding with some rod meant for gas welding which I though might have been contaminating the weld. I switched over to some stainless rod which helped. I tried several different electrodes in different grinds and none of them really resolved the problem. I tried lowering the flow rate of argon to 15CFH and it didn't help. I was reading over on the Miller website the tig handbook which recommends the 1/16" electrode for the amperage I was using although the recommended settings that came with the machine recommend the 3/32" electrode. Does this sound like an electrode size issue or something else?

[masawemps]

Are you sure the issue isnt just the quality of your helmet? some auto helms aren't very good for tig welding you need to have at least 3 to 4 arc sensors or you will randomly get flashed.just a thought as this has happend to me before and ever since i got a better helm no problem also if you have a helm where you can adjust the sensitivity then try to turn that up a little it may help

[domino]

It was never a problem before, but it could be.

[kermdawg]

Go to home depot and buy one of them cheap 20 dollar flip down helmets and see if that solves your problem. Really sounds like a helmet problem.

Also- you cant use gas welding rod for tig welding. Different stuff. As for welding with stainless rod on your mild steel, thats gonna give you a pretty brittle weld I would think. Just pick up some er70s-2.

[Otto Nobedder]

This is clearly a hood problem. There's nothing a TIG machine can do that will blind you through a fixed glass lens, and I've TIGged with a #9 shade.

Steve

[sschefer]

This is clearly a hood problem. There's nothing a TIG machine can do that will blind you through a fixed glass lens, and I've TIGged with a #9 shade.

Steve

Agree, he's got a funky sensor or maybe a bad battery.

[domino]

i will try and recharge the hood and see if that is the problem.

[Otto Nobedder]

domino,

Please don't use a "Harbor Freight" or similar hood for TIG. You need the fastest response time you can get, and four sensors or better. When TIGing, you will OFTEN be in the shadow of your cup and your hood will have to react again when the shadow passes. Your eyes are worth far more than a top-quality auto-hood costs. Trust a half-blind 42-year-old on this.

I use nothing but old-school fixed lenses in a flip-down hood for TIG. This never fails unless you get a crack in your hood. It's a lot cheaper, too. A lightweight Jackson with the large window costs about $25 with the lens.

Steve

[kermdawg]

I use nothing but old-school fixed lenses in a flip-down hood for TIG. This never fails unless you get a crack in your hood. It's a lot cheaper, too. A lightweight Jackson with the large window costs about $25 with the lens.

Im gonna post this somewhere so I dont have to keep rewritting it, but everytime someone has a problem with their auto-dark I think of this story my tig instructor told me. He worked with this guy who had always welded with an auto dark, and one day his helmet took a shit in the morning on the job, and all he had to replace it with was a flip down. His welding skills immediately dropped through the floor, cause he had never had to flip his head down before and he kept strikin his arc in the wrong place. He went home early that day.

So I was taught to use flip downs, and I always will. Theres NOTHING wrong with auto darks, but I believe you at least need to know how to use a flip down, just for the above situation. Specially with tig, Ive heard lots of stories about people gettin flashed, and yuo need a high quality auto dark for tiggin anyway. I tig (and stick) with my 20 dollar home depot helmet, and it works just fine. Popped out the number 10 lense for an 11, helped the eye strain a bit. But other than that, no problems.

[Sarge]

I find that my lens shade is governed by the amount of light where I am welding. If it is a darker shop, I use a darker #11 lens. If it is a well lit shop a drop to a #10. The amount of light coming in from the back of the helmet sets the mood for my ability to see clearly. I keep both shades for just such occasions. Just sayin....