Ceriated tungsten going blue?

When welding 3mm ali section with a 3/32 ceriated tungsten at around 80
amps the tungsten is balling and turning blue. Is this a bad thing? I am
totally new to ali welding, machine is Migatronic 220 AC / DC. I suspect
it's not a good thing... :) Thanks
Reply to
Chris
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If your welding using AC current, the tungsten balling is normal, however if your using reverse polarity, the balling will be extreme.
The tungsten turning blue is due to a lack of gas coverage. It could be you don't have your post flow timer set long enough. Also check the flow rate of the torch gas, set for 15-25 cfh. Be sure there are no drafts in the weld area as that would affect the gas coverage.
Richard
Reply to
AMW
Thanks Richard, this maybe confirms a worry I have that gas flow from the torch is not what I would expect from the flow on the flowmeter, it's barely audible with the torch to your ear. I wonder if there's a leak within the machine itself... Cheers.
Reply to
Chris
I agree with the gas shortage , Argon or mixture should be flowing at 10 to 20 CFPH , as stated before , you should be in the AC mode , 3/32 tungsten sounds a bit small for 3 mm or 1/8 in. alum., I would use 1/8 in. Tung. 2 % thoriated , using Reverse Polarity for a brief time on some scrap alum. is a quick way to get a ball on your electrode, if it's working OK , you should be able to shave in it. Good Luck Phil
Reply to
Phil
Phil you are getting your tungsten mixed up, thoriated isn't for AC zirtung is best most of the time and a 3/32 zirtung will work fine for 1/8 alum. up to 150 amps Dave
Reply to
Dave P.
Dave , all the welder's that have been welding Alum. aircraft and aerospace parts for the past 40 yrs. or so will be sad to hear that thoriated tungsten does not work , actually 2% Thoriated has been the standard forever , both for steel and non ferrous metals in the aerospace industry , having been a mil. spec. qualified welder for a major aircraft corp. , I can assure you that this is so , in recent years there has been concern about the radioactive part of thorium doped tungsten , some manufactures have switched to other material , lanthanum or lanthanated tungsten has started to take over for safety reasons , hope this will help to clarify this question. best wishes Phil.
Reply to
Phil
Dave While Phil didn't state that 2% doesn't work, I would agree it's not the first choice, especially for x-ray quality work. I too have welded in the aviation industry. 2% will weld Aluminum, however as you must know the ball doesn't hold up well, and with 2% and AC current you run the risk of tungsten coming off and into the weld, and then it doesn't pass x-ray. Zirconium tungsten has the advantage of holding the ball shape very well and you don't run the risk of tungsten contamination.
Richard
Reply to
AMW
Richard you said it better than I did. Sorry Phil, I hate typeing so I tend to abreviate, didn't mean to say it wouldn't work I've used it myself with helium mix to get better pen., it can hold a smaller tip than zirtung for a short time but requires a lot more maintenance when it starts to erode, whereas with a properly dressed zirtung I've had them last for 2 - 3 hours on a good day (bad day 2-3 seconds) . I should have said that thoriated probably isn't the easiest choice for a beginner on AC alum.
Reply to
Dave P.

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