Hi guys,

the regulator on my MIG for the little hobby bottles stopped working, so I hooked up the big Argon cylinder I have lying around - left over from my dead TIG.

Now I can't get a decent weld from it, almost no penetration, very spattery and the wire seems to be melting back into the torch.

I'm guessing I'll just have to go and swap the argon cylinder for a CO2 or mix one, pity though as there is about 50 quid worth of argon left in it.

Argon for aluminium welding, C02 or mix for steel, thats about it.
So try and sell the argon to someone wanting to weld aluminium

Shame your in S Wales I would have swapped you for a big bottle of CO2 mix.
Cheers,
Bob

I've used pureshield argon and argoshield light to weld steel without major problems. (Both have some C02) Pure argon can be used, the weld is slightly taller and narrower, and does 'wander' a bit, but it should still give a decent weld. It sounds as if the gas flow is too low/regulator not working.
Regards
Hugh

Sorry splitrivet it's a rental cylinder anyway.

Hugh, I've tried upping the flow right up to 13L/min, then the wire just forms droplets of metal which drip onto the workpiece. Dropping it really low to about 2L/min and it blows bird poo type welds.

Is the TIG terminal, cant you get it fixed.
Cheers,
Bob

hi frequency arc start stuck permanently on, that I could live with, but when I tried it again yesterday the gas solenoid was playing up and I blew some lovely big holes in things.

It's a cheapy chinese import, looks like a case of getting what you pay for.