Tig Welding Failure, what am I doing wrong

[woodlandfarms]

OK, my setup....

Scratch Start Tig
100% Argon
#6 Cup
Matheson Select 3.32 Blue Tip E3 Tungsten Electrode
Everlast PowerArc 200st



Setup for 16 Guage Mild Steel
25 Amps on Meter
15CFM on Argon

Results - A lot of burn through.



Setup for 24 Guage Copper
20 Amps
15CFM

Results - Incineration. By the time I got a puddle I burned through. I tried laying some filler copper on top, see if that would help, torched right through.



While I am a beginner, I am not sure the issue is me. Maybe 20 Amps is too much for this stuff (WOO HOO I get to buy a real tig machine) but I think not. All the charts and while none I have found mention 24 guage copper, it seems to me that I need a lot more than 20 amps to make it happen.

Looking for any and all comments.

 

[Mark @ Everlast]

What is your polarity on the torch?

 

[woodlandfarms]

Negative to the torch, positive to the ground. It seems to spark right.....

 

[TMGT]

Did you try upping the shielding gas flow? Also make sure it's actually flowing out the torch.
Had a problem a while back that ended up being a slightly lose adaptor on the regulator, drove me nuts for awhile until I found it when I replaced the regulator.

It was actually pulling air in and contaminating the shielding gas.

 

[Shield Arc]

My PowerArc 200ST runs about 10 to 15-amps hotter than any of my other welders. I've never been very good at welding that thin of material. There was a time in my life where I thought 3/8-inch thick metal was sheet metal. I think something that thin, a foot pedal would come in real handy.
Here is some Tig welds I made with my PowerArc 200ST.

 

[woodlandfarms]

Well, been doing a bit of reading. Going to try reverse polarity today. see how that works.

But in the end I think it is my wonderful and very powerful Everlast 200. I always felt that bad boy was hot, but with Shields comments I am now confirming that that little box is a great stick welder.

 

[Shield Arc]

with Shields comments I am now confirming that that little box is a great stick welder.

Oh it is! I own some of the best welders ever made, and this little PowerArc 200ST is very impressive! :thumbsup::thumbsup:

 

[swines]

I'm finishing a project using 16-gage steel tubing. I use a Thermal Arc 185 Arcmaster TIG with a #8 cup, gas lens, 3/32 2% lanthanated electrode (blue color code), and a 12 CFH flow rate with Lincoln ER70S-2, 1/16 filler rod.

The general rule for steel is 1 Amp / 0.001 inch of thickness. 16-gage steel is 0.0625 in thickness - meaning the starting setting should be around 62 Amps (maximum current level). I run my welder at 65 Amps maximum, but I have both a foot pedal and a finger tip control (TIG Button made by TIG Control) to control the arc, which in turn, controls the heat input to the metal.

What I have found with thinner metals, is that if you don't have a way to control the arc intensity, the metal rapidly overheats and - you burn a hole through it. Typically, I start the weld at nearly the full pedal (65 Amps) and when I get a liquid puddle, I back off and continue the weld at about 30-40 Amps. I also use a fairly rapid travel speed, and for some joints, setup the welder in pulse mode to lower the total heat input. The pulse mode I use is 90 Amps maximum, 40 Amps background, 33% on time, and 1.3 pulses / second.

Without a way to control the arc you're going to have a difficult time managing the heat input to the metal, and puddle versus travel speed. If you're attempting to control the heat through simply using a lower Amperage setting, without a foot pedal (or other arc control) the problem you will have is that you have to dwell too long in one place to build up enough heat to create a puddle. Essentially, you're heat soaking the metal, and then have no way to reduce the heat input, so you're burning a hole through the metal.

That's why it's important to start hot and then back off the arc current as the high level starting Amperage creates a puddle rapidly without heat soaking the metal. Once you have the puddle established you can back off the arc level as the steel heats up.

Without that kind of control, it's difficult to weld thin material.

I also have a theory that the steel today must be alloyed with Chinesium which has carbon inclusions that burn through rather than melting....but, that's just my theory.

I do know that 25 years ago, the steel tubing I was welding never burned through even at higher Amperage levels...hence the Chinesium theory....

 

[dragoneggs]

Chinesium... funny! :laughing:

 

[woodlandfarms]

Yup, I hung up my scratch tig kit today. I reversed the Polarity, and while it spread out the heat, once the copper got hot it still just vaporized no matter how I moved. It is clear to me that the 20 amps my meter reads on my welder is more like 50.... There is probably some way to check this...

Anyway, I did tig on thicker metal, and it works pretty sweet. Slow as snot but I get it and I get how cool it could be.

The downside is that I am 100 in the hole on a scratch start tig system I will not use. The upside is that I see a nice tig rig in my future.... Tigging is pretty cool, I don't want to say easy but I get how it is an attractive way to weld.