lift arc whoes... can anyone lend a hand teaching me to tig??
 

i bought an arc tech (cemont) lift arc tig welder from egay last week. Just got it all set up today and started striking my first tig arcs. here are my problems:

tungston keeps sticking as i pull it up off the metal?? wtf i thought that was the point of the lift arc?

after i get it going a little bit, the tungston balls up and i get some arc wander, but enough to keep a straight line. Then after i weld a straight line for a little bit, the tungston erodes close to the cup and the arc stops.

heres what ive got going on so far. 18 cfh of 75% argon 25% carbon dioxide (is this the problem?? I got the tank and regulatior for free from a buddies work. The tank had less than a 1000psi in it so i figured id run it out before i got it refilled with pure argon.)

how much should the tungston stick out of the cup? Only 1/4 to 1/8" right?

thanks

Re: lift arc whoes... can anyone lend a hand teaching me to tig??
 

I stick the tungsten out just enough so the base of the cone is almost lined up with the end of the cup.

Don't touch the tungsten to the metal and it won't stick

edit: didn't see the lift-arc part... never used one of those.

Re: lift arc whoes... can anyone lend a hand teaching me to tig??
 

The reason you tungsten is balling up is it is eroding due to the improper gas. I've treid mix gas once or twice when I ran out and was in a bid. I have tried 80/20 Arg/Co2 and 90/8/2 Arg/Co2/Oxy and the cause the tungsten to burn up.

As for scratch starting, it sucks, never used it on tig, but I have on REALLY old Stick weldering without hot starting electrodes, it's hard!!!! I don't know if you have to touch, or if you can just get close enough for the arc to jump to your material.

Re: lift arc whoes... can anyone lend a hand teaching me to tig??
 

Yeah, the big problem is the gas. You CANNOT use any misture that includes CO2. You need argon, 100%.

Re: lift arc whoes... can anyone lend a hand teaching me to tig??
 

the welder is a lift arc, meaning you touch the tungsten to the work for 2 seconds, that creates a low voltage short in the welder. When you lift the torch, the arc starts. The tungsten doesnt get contaminated at all. Miillers welding manual makes it seem like its better than hf. I got it welding decently though, it still goes through tungsten pretty quick though. The bottles pretty much empty now, so ill get it refilled with pure argon on monday.

Re: lift arc whoes... can anyone lend a hand teaching me to tig??
 

yea i use 100% argon when i weld, and my tungsten never erodes, i

Re: lift arc whoes... can anyone lend a hand teaching me to tig??
 

i also have a scratch start....i never play'd with it but i am this winter when i pay somethings off..let me know how it does the job....i want to build a mani for my next project and i never tig'd in my life...

Re: lift arc whoes... can anyone lend a hand teaching me to tig??
 

My miller maxstar is a lift start and i dont have any issue's with it balling up. I'm using 100% argon though.

Re: lift arc whoes... can anyone lend a hand teaching me to tig??
 

yea it was the gas.. works pretty well now. I'll post up some pics when i get a few more hours of practice.

Re: lift arc whoes... can anyone lend a hand teaching me to tig??
 

If you dont have a gas lense, get one. Its night and day :y

Re: lift arc whoes... can anyone lend a hand teaching me to tig??
 

Pure Argon or pure hulium only

Re: lift arc whoes... can anyone lend a hand teaching me to tig??
 

When you use lift arc...how do you stop the arc?

Thanks
Randy

Re: lift arc whoes... can anyone lend a hand teaching me to tig??
 

Scratch Start (Lift Arc) you simple drag your arc to the edge of the work piece and then pull it away to break your arc

Re: lift arc whoes... can anyone lend a hand teaching me to tig??
 

nah bro.. scratch start and lift arc are two totally different things. Kinda like harbor frieght and miller :y

Re: lift arc whoes... can anyone lend a hand teaching me to tig??
 

Hobart is harbor frieght and they use the name lift arc so does Miller ;)

Actully Scratch Start is another term for Lift Arc. Lift Arc is used on machines that don't have high frequency. For example Squarewave and Syncrowave. The start frequency is 60hz. Thus making the current jump from the work piece to electrode. The waveform looks like this http://content.answers.com/main/cont...nomenon_50.jpg

If the machine has a polarity setting make sure to use these settings
DCEN(Direct Current Electrode Negative) it will be used on mild steel and stainless steel.
DCEP(Direct Current Electrode Positive) Titanium cant take the heat steel can.
AC(Alternating Current) Aluminium

Direct current flows from the negative to the positive. AC alternates from DCEN to DCEP at 60hz.
DCEN the weldment gets hotter than the tungsten. AC gets equaly as hot

sloppy post you get the point though

Re: lift arc whoes... can anyone lend a hand teaching me to tig??
 

Lift-arc and scratch-start are two different things. Scratch start it for machines that don't have high frequency. My Thermal Arc 185 has a Lift-Arc setting. Do don't have to scratch the material in hopes that it doesn't stick or get contaminated. When in the Lift Arc mode there is a tiny current going through the torch. Then you touch the work piece with the tungsten, you can hold it there pretty much as long as you like. When you lift the tungsten from the work piece after about a second or so the high frequency kicks on and starts up the arc. Works great when I need to walk away from my pedal, but I just have not figured out how to kill the arc. Pulling it away form the work piece while cranking 140 or so amp is a bit freaky and leaves a nasty spark trail on the part.

Later
Randy

Re: lift arc whoes... can anyone lend a hand teaching me to tig??
 

Thank you!

For a nice animation of lift-arc:

http://www.millerwelds.com/products/.../lift-arc.html

Re: lift arc whoes... can anyone lend a hand teaching me to tig??
 

i was wondering the same thing!! What ive been doing is cutting down the angle of the torch and holding it closer to the metal to get the pool really small, then pulling away somewhat abruptly. i know its not the best for the strength of the weld, but if i do it when its real hot- a large flame will blow in the direction of the arc

Re: lift arc whoes... can anyone lend a hand teaching me to tig??
 

Thanks jagojon3. I stray away from lift arc and scratch start. Welding transfer pipes you have to use a pedal. Cant have undercut (gouging) on the welds edge. Pipes run over 300psi.