Thanks for the comments chaps.
Hi Andy
Not to speak for Barry but I did find this post he made some time ago. Maybe he has changed things since. Not sure.
"On the last course we hooked up someone's DIY welder to pure CO2, tried it, and then flicked to my manifolded supply (to run two MIGs from one bottle) of CO2 / Argon mix. The difference was remarkable, and definitely very noticeable. You wouldn't want to return to pure CO2 after running a MIG mix,
One thing I have never understood is that if you use pure Argon with a MIG welder on mild it's horrible, and yet with a TIG, again on mild, it's gorgeous. You'd have thought the weld conditions would be the same, but obviously not.
As a matter of interest, I'm gradually switching my bottles from rented Air Products ones, to Albee bought ones. It's a hefty investment for the likes of me as I run two MIG bottles, one argon (for the TIGs) and oxy acetylene. Amazingly though, the payback is just one year, so the availability locally of Albee has been a godsend.
Oh yes welders: I absolutely love my two Kemppi's (a MIG and a TIG, both small and beautifully made). My more recent R Tech AC DC TIG has been very good as well, but I don't love it. Not sure why, perhaps because it's a blend of China, Germany and a little bit of British. Good back-up though.
I've always thought it a cruel irony that the cheaper DIY machines are by far the hardest to use: inconsistent, fussy and cantankerous, all qualities a DIY'er can well do without. Give a pro machine to a DIY chap, and his welding will improve tremendously. Give a DIY machine to a pro welder, and it'll be through the nearest window within 20 minutes
.
A quality machine is a joy indeed
.
Anyway, if space is an issue Graham, check out the Kemppi range of inverter MIG's. They are not much larger than a big handbag, and can be popped in a cupboard or on a shelf. I've had my one for eight years plus, so it's probably gone through 75-100 kilos of wire. Never missed a beat, and always a pleasure to use. It's never tripped out through overheating, and will happily weld from translucent lace, right up to very heavy plate. On the lowest setting you could almost weld something held in a bare hand: I've never had to turn it so low in eight years. The only downside is there's no shock-and-awe. They are expensive, and when you show your friends they'll think you've been conned into buying a tiny DIY machine from the toy shop.
One thing to do with all welders is regularly blow them out with compressed air (outside). They do attract grinding dust, which is most unfriendly to electronics."
Regards
Mike