Which welder

Thought gas welding wasn't as suitable for car stuff (thin) due to distortion? Mig keeps the heat more localised?

No that's incorrect advice

yes

You can't gas weld high strength steels. If it's not got any of those you can gas weld it but Migs still quicker & easier.

Who'd like to bet that this:

was welded with CO2?

CO2 can't be used for MIG, but it does have limited use for pulsed- transfer or dip-transfer MAGS on thin steel.

It can't be used for spray transfer, so forget it for thick stuff (including kitcar spaceframes or suspension components)

You can't afford a machine that does pulsed transfer

You can only do dip transfer with CO2 if yoru technique is good. if it isn't, it'll tip you over into globular transfer mode instead, aka pigeon crap welding.

Just avoid CO2! Switching to a decent shield gas is (along with an automatic hat) one of the biggest improvements that any amateur welder can make to their results.

IMHO, thick aluminium is OK fed up the whole torch cable, but you should keep a separate liner for doing this.

Thin aluminium is easier if you switch to TIG

Spool-on-gun feed is fine, but they're expensive and IMHO only for bulk fabrication in thin stuff.

Andy Dingley gurgled happily, sounding much like they were saying:

Does CO2 make pigeons incontinent, then?

To be fair to it, that picture looks like a gasless set running at too low a voltage, possible with gas wire (the wire is melting, but there's no penetration of the base metal). It's not quite the classic globular transfer.

bollox!

I've made yards of railings, ornate gates, and loads of old tractor,dumper/whatever repairs etc ALL with CO2....

Cheers Jim K

Jesus. And I thought *I* was a crap welder.

What do you think the "I" in MIG stands for? If you're using CO2, it's by definition not MIG and just MAGS (and so works rather differently).

Well following advice on the welding forum i bought a Clark Pro90 today it came with a Co2 bottle and i bought an Argon/Co2 mix bottle. I will practice with both of these before i decide which large size bottle to buy as there is such a large difference in price. On the way home i was passing the local fire station which was having an open day, they were cutting the roof of an old Astra, so i managed to get the roof and bonnet to take home for welding practice. Thanks for everyone?s comments, although their still seems to be a Co2- Argon/o2 divide if anyones interested i will report back how the Novice managed.

strewth... but you do agree you can weld steel together using CO2 as gas in what's commonly known as a "MIG welding machine"??

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I agree - that's exactly what I did and used the kit at home for many years without any problems. I always used my home address when getting new cylinders and BOC never queried it. I re-silled and A-panelled a Mini with it - including using lead filler - a great learning experience :-)

However the main problem could be your home insurance - welding cylinders within a certain distance will invalidate it! If your garage is attached don't risk it but if it is at the other end of your garden check the distance.

Slatts

A skilled gas welder can weld car bodies. I saw a resto on a Jag once where this had been done; they said too that the weld bead is not as hard as with MIG so it could be planished flat with a hammer rather than doing so much grinding.

The old workshop manuals recommend placing wet asbestos around the weld to contain the heat!

"Sla#s" gurgled happily, sounding much like they were saying:

Presumably MIG cylinders are perfectly acceptable?

Agreed, I use plain CO2 all the time, no problems.

Much cheaper now, mine was about £40 and worth every penny!

yer pays yer money etc -

NB check the link I gave earlier - on that webpage is another (referenced) link to a practical test/comparison of CO2 vs argonmix gases on steel using MIG welders. Lots of notes and pics.

Good luck and have fun!!!

pics always welcome ;>)

Jim K

yer pays yer money etc -

NB check the link I gave earlier - on that webpage is another (referenced) link to a practical test/comparison of CO2 vs argonmix gases on steel using MIG welders. Lots of notes and pics.

Good luck and have fun!!!

pics always welcome ;>)

Jim K

That's rubbish. I use plain CO2 from pub bottles all the time for MIG on thin car body steel. My welding is fine. You can see it in the pictures in my build threads, eg