What gas?

[Randall977]

Old question I'm sure but what gas should I use for car body welding? I've just bought a Portamig 215 and will be practicing on scrap to begin with. Someone mentioned that pure Argon is best? I'm in Oxfordshire and have looked at this website for renting gas http://www.adamsgas.co.uk,does it look okay and what size should I go for?

Thanks, Christian

 

[gavuk]

Not pure argon unless welding alluminium ,argon/co2 mix is what you need ,lower co2 content for thinner material,higher co2 for thicker section steel

 

[backpurge]

Argon is a definate no, no.
For best results use a mix of 2% O2, 5% CO2 balance argon

 

[GrahamGKD]

Adams list an 'argoshield light' equivalent - that is the one you want.

 

[gavuk]

as above ^.....argon 95% co2 5%...known as argoshield light,..... for car body welding...

 

[backpurge]

as above ^.....argon 95% co2 5%...known as argoshield light,..... for car body welding...

Don't wish to appear knobby but Argoshield Light is a 3 component mix, it has 2% O2 in it, as does all the rest of the Argoshield range and the vast majority of gases designed for welding carbon steel made by APL, AL etc etc

 

[gavuk]

Don't wish to appear knobby

....i stand corrected ...Adams gas had used it as a description (in brackets)....lol....i was trying to use the terms they (OP and adams gas)would recognise....most of the weld will end up as grinding dust anyway ....we won't fall out over it

 

[Pete Rodder]

I've just asked this on another thread but is Argoshield Universal any good for 16 -20swg
mild steel(VW Beetle)? HSS Hire shops will supply an X size cylinder refill for under £38 inc VAT but can't do Light.

 

[gavuk]

Universal is meant for 4-10mm(iirc)....due to higher amounts of co2....can't remember using it on thin steel .i would imagine its hotter,more splattery than light but still easier than co2 ,with a more stable arc and more fluid weld pool than co2 ,but get some more opinions as i use co2

 

[droopsnoot]

I'm on BOC Argoshield Light, right at the very bottom of the cylinder and just using it up until it stops. I noticed that the last few welds I did yesterday were very much better than usual, and I wondered whether it's possible that I'm welding with pure Argon. In my mind I want to say it's perhaps not mixed, but I don't think mixed gas works like that - as if it has to be stirred properly like a powder into liquid might. It's my imagination, right?

 

[Wozzaaah]

Pure argon would give you horrible looking tall welds which is why it's not generally used for mig welding. More likely you had other parameters just right, torch angle, wire stickout, travel speed etc.
.............Now, if only you could remember what they were for next time....

 

[droopsnoot]

Yes, exactly the trouble.

 

[Wozzaaah]

Thanks for that Honjon, I'll add them to the map.

 

[madkayaker]

yeah, i'd stay away from pure argon too. I use the 5% CO2 mixes cause I rarely go above 4mm - its good up to 5mm. you could probably push it to 7mm but if your welding that for any length of time you should get yourself a 15% mix. found an ad in classic car weekly for www.hobbyweld.co.uk they're doing those mixes but in larger rent free cylinders. I might give them a go. they have a place to pick it up near my neck of the woods. I'll let you know what it goes like.

good find even one in carlisle