How do I keep my tungsten from fouling? Literally every time I stop the arc I have to grind a new point on it.
I'm not dipping it. I'm welding 3mm aluminum and already dipped it plenty of times so I know what it's like. Maybe metal vapor is building up on the tungsten?
I've tried different flow rates and am pretty sure the gas flow is adequate. I can weld a good bead, the electrode is just fouled as soon as I take my foot off the pedal.
The electrode is either totally inside the cup or sticking out 3mm (in a 10mm cup).
Use a gas lens, a cup slightly larger than said gas lens, and try to minimize draft. Too much gas can actually cause turbulence that mixes oxygen into the shielding gas. Though a bit extreme, I've been considering feeding filler with a gas-shielded MIG gun.
Yeah, initially I had the gas too high and it was blowing air into the weld. I lowered it until I got no turbulence. I am using a gas lens. And I have tried a bigger cup, with the same results except I need more gas flow.
It has to be a total noob mistake because I just started welding.
Sorry buddy you're not on Stack Overflow anymore. But just for the heck of it:
3mm aluminum, butt joint
2.4mm filler, 2.4mm tungsten, 10mm cup with gas lens, 3mm stickout.
100% argon, 8 l/min (17 cfh)
AC 115A, 60hz, 50% +/- (my machine can't adjust frequency or cleaning cycle).
I don't know about fouling, but a 50% split could be melting your tungsten. Use a larger size.
Yeah good point, it does ball up pretty fast
It would help if you actually posted something useful like what settings you're runnning and what machine you're using.
What color tungsten are you using? I don't know much about tig. Have one and have used it sparingly, but i do know some colors of tungsten don't play nice in certain applications...
Green
I heard the green ones are shit
Sounds like a gas post-flow issue where as soon as you shut off the current the gas stops and since the electrode is still hot it reacts with atmosphere.
Green (100% tungsten) should be fine but you basically can't expect them to keep sharp. Its ingrained as a fact that AC welding rounds your tip because green 2.4mm is what most people ran with AC. Some high end machines comes with a separate setting in the polarity modes that you switch too after you've dipped the tungsten and removed the contamination where all it does is run AC with strong balance towards + to round the tip quickly They do that just so that you can then switch back to your normal AC settings for welding.
Ideally you want it to look like pic related. Shiny and round. Once you get a ball that's thicker than the electrode itself at the tip you're welding too hot and you should normally fix it with balance but since you can't do that your option is to pick a a larger electrode or a different electrode type that handles heat better.
Thanks
I know you know this, but for other readers:
Ive been using an inverter TIG machine with a 2% lanthanated electrodes. By adjusting the balance I can weld Al and maintain a sharp tungsten. Having a sharp tungsten allows you more control over the arc; it wants to wander less.
The old school transformer machines didn't allow adjusting balance; the arc was also fixed at 60Hz. Balling the electrode is just what you did for Al. Now, not so much.
I have a gold tungsten in the shed somewhere, after I get my hose fixed I'll try it
Don't think tungsten really matters as long as your not using thorium for AC.
Are you sharpening to a point like for stainless steel? For aluminium the tungsten should be rounded
Yeah I am sharpening to a point. It seems to work ok (until I shut the arc off) but I'll try it rounded.
Ok upon further inspection, It looks like my hose is blocking the gas flow. It has an internal, uninsulated, stranded power cable that has been unraveling and clogging the hose. I didn't see it before because it only happens when I have the hose twisted into certain positions. Just putting this here in case anyone else has the same problem.