Buying a tank local around here is ridiculous price wise. So I've found tanks cheaper elsewhere but have no real assurance that they've only been filled with 100% argon. If it were filled 75 25 before, and bleed empty, traces of the other gas would remain. How worried would I have to be about contamination while welding if it was then refilled with 100% argon?

 

Nah, I've been on the site for awhile just reading and the likes. I was just curious because the welding supply shop guy was talking how once a tank was filled with another gas it is contamintated, which makes sense. So the small amount of trace gas shouldn't have an adverse effect contaminating the weld?

 

I was wondering the same thing. This is HMT, safety isn't an issue.

 

Its a trade in type of deal, not a refill. just trade it in for what you wan.t

 

Yeah you bring yours in and they just hand you another full tank.

 

they dont change what goes in the bottles. if the bottle originally came with 100% argon it will always be filled with 100% argon. and if you can find a "tractor supply co." (thats the store name) their refils are super cheap compared to welding shops.

 

the place i go doesnt care. they will swap any bottle. the only problem is you have to take a regulator with you and check the bottle cause the last one i got was half empty

 

I can't really trade in the bottle for a new one since I was planning on getting a 55cu tank for around $80 empty. The place where I'd be going to fill it only has 100% argon tanks of 20cu (for around $100 filled) and an 90cu or 110cu (i forget which one) for around $220'ish. Therefor I can't sign up for there exchange program for $7 dollars a year, meaning if I wasn the tank filled all the way up there is a 1 week turn around as they ship it out. Yet, I'd just figure I could have it transfilled there which would take only a couple minutes, and I'm only paying for the gas so if it isn't filled all the way up I don't really care since they are only 4 miles away and the tank would be fairly easy to lug around. I do have a tractor supply company a hundred yards away from the welding supply place. I thought they only sold a 40 cu tank, and Ihad no idea they filled or exhanged tanks.?