A mate wants me to weld some 304L stainless sheet into a BBQ smoker for him. I've already got the stainless filler wire and use a large cylinder of BOC Argoshield for welding mild. The chappie at BOC once told me one could get away with using Argoshield to weld stainless but it was better to use their Stainshield gas. I don't think stainless shield gas is available in the small cannisters which is probably all I'd need, unless anyone knows any different?
Can I get disposable bottles of Stainless gas?
Would Argoshield work?

You want pure argon for welding stainless steel. You wil be able to buy small bottles of pure argon which will work beter than your argoshield. Oli.

Small bottles of Argon are available from Halfords for about seven quid. Machine Mart do them too, but for twice that.

ATB

Simon

I've got the 1st October 2007, BOC gasses price list in front of me, there are 4 mixes of argon.

Ideally, you need Pureshield Argon for stainless, which is pure argon.
The other 3, Argoshield Light, Universal & Heavy are all mixes with (I think) carbon dioxide. I tried using argoshield light once for TIG'ing stainless (cos it is 2/3 the price of Pureshield Argon), but whilst it worked it was harder and the result wasn't as good.

Argoshield is a mig mix not tig. If you mig stainless with mixed gas you will get impurities from the carbon and the weld will discolour and rust. Tig will eat the tungsten with Argoshield.

I have, just today, been Mig welding my stainless exhaust flanges to the starter pipes, (oval to round). I use Argoshield light, and the weld is clean and neat. So in my opinion the obtaining of pure argon, whilst very nice, is a pure waste of money, unless you are welding alloy, then its an essential. But then thats my opinion, not every one would, or does agree. Ray

I'm with chippy here, if it's not something safety critical I would (and have) just use what ever gas you normally use, results will look fine. If in doubt test on some scrap first.

Davie

My 2 cents...
If it is going to be used on aBBQ, it will be exposed to High temperatures, and carbon, it will eventually stain...

Chippy, you're right but that's for MIG not tig. With tig you'll knacker the tungsten as pete said


edit, I'm an arse, he's using MIG, so yep, I agree with chippy, use the argoshield!

Bloody hell I've welded enough stainless with mild steel filler wire and co2 let alone argoshield!! It isn't pretty but it will do the job!

[Edited on 23/9/07 by NS Dev]

It was JohnN who tried tig with it Nat. As noted it's for a stinky old barbie so who's going to care what it looks like as long as it burns food .