Contaminated welds TIG

[SimonM]

I’ve been forcing myself to only use the tig welder lately when welding steel. Since I bought my primeweld 225, I’ve used it a lot for aluminum but kept on using the mig for steel other than a few practice beads on plate.

The results have been mixed but I usually get a satisfactory weld and I am slowly figuring how to wrap the corners on square tube. Then, it seemed I was getting contamination with greyish and slightly wrinkly welds.

Made sure the metal, filler rod and tungsten was cleaned to perfection with acetone, was getting the right amount of gas and that the gas was making it’s way to the torch. Still getting the same issue...
Tore down the torch and found a distorted collet with a bulge. Quick internet search and I landed on this video that explain the issue.

Turns out collets are consumable and should be replaced once in a while.

 

[wharris1]

thank you

 

[Hruul]

Thanks.

 

[RobinHood]

I will need to test this theory, as I am having the same problems. It makes a lot of sense what they are saying.

 

[SimonM]

I didn’t have a spare collet at the time, just used a file to get rid of the bulge to test the theory and it solved the problem right away.

 

[DavidR8]

Split collets are definitely less durable than wedge collets. I prefer wedge collets when I can find them.

 

[RobinHood]

Thanks @SimonM for the video and the confirmation. I know my collets have bulges. So will need to address that issue first - and not torque them down as tight while they are hot going forward. That was my mistake in the first place. Plus I have cheap collets that obviously need some work out of the box. But I have the tools, so add it to the list of projects...

 

[CalgaryPT]

I’ve been forcing myself to only use the tig welder lately when welding steel. Since I bought my primeweld 225, I’ve used it a lot for aluminum but kept on using the mig for steel other than a few practice beads on plate.

The results have been mixed but I usually get a satisfactory weld and I am slowly figuring how to wrap the corners on square tube. Then, it seemed I was getting contamination with greyish and slightly wrinkly welds.

Made sure the metal, filler rod and tungsten was cleaned to perfection with acetone, was getting the right amount of gas and that the gas was making it’s way to the torch. Still getting the same issue...
Tore down the torch and found a distorted collet with a bulge. Quick internet search and I landed on this video that explain the issue.

Turns out collets are consumable and should be replaced once in a while.

Kevin has some good tips and a nice shop. Sometimes he is too hokey for me, but better that than the that fabrication guy who mixes all he words up purposely and thinks he is a comedian. To each his own I guess.

 

[cuslog]

Interesting, I don't think I've ever had that exact problem but I'll have to look at all my collets now.
One gas flow problem I have experienced was with gas lens cups - the screen of gas lens cups getting partially blocked by splatter from "dunking" the electrode (yes, I do it sometimes too) - ended up peeling the screen out, couldn't get the deposits off the screen.

 

[Jay R M]

I would recommend using the "jumbo" set up, and yes wedge collects.

 

[CalgaryPT]

Clogged screens are a common cause of weld contamination in TIG. Personally, I don't like screens for this reason. They are on my pyrex cups, but I wish they weren't. I've used a Weldcraft WP-17 torch for probably 20 yrs. They are the standard 150 Amp air cooled torch that comes with larger Miller TIGS. They aren't screened, and I never noticed the difference in my welds. I think if you are a pro you might, but for the type of TIG weldor I am, I see no advantage in screens. They all clog eventually anyways, so I stick to the standard unscreened torch that came with my Miller and have never had a gas flow/distribution issue without screens. A fellow I know who is a much better weldor than I am calls them "gimmicky consumables."