Gas use

[Sidecar Keith]

Just got my new 151TE today. Did a couple of practice bits then about 2 meters worth of welding, before the welding starting looking oxydised (brown) I'm assuming this means the gas has run out, is that about the correct amount of weld I can expect to get with the disposable bottle that cam with the welder?

Keith

 

[madkayaker]

sounds about right they are very poo

 

[Wozzaaah]

Yes, that's about right Keith. Around 7 minutes of continuous welding is all you can expect from a disposable cylinder.

 

[Sidecar Keith]

Righty ho, off to air products tomorrow for a big gas bottle.

 

[chunkolini]

It makes life so much cheaper and less hassle, do you have a regulator? and get the right gas mix, cant remember which I use I think it is an equivalent of Argosheild Light, Argon, CO2 and a smidge of oxygen which did confuse me at first, but it does help.
Good luck, Chunko'.

 

[Sidecar Keith]

I think the Air Products version is called Ferromaxx 7, a mix of Argon C02 and Oxygen.

 

[weldingscotty803]

you dont want any oxygen in it keith. thats what causes porosity. you want there couger 5 or argoshield light

 

[wyn]

There is a handy table of the differences between the various gasses available, here.

 

[Paul.]

you dont want any oxygen in it keith. thats what causes porosity. you want there couger 5 or argoshield light

Gas mixes for mig do contain 2% oxygen, for example argoshield light, is 5% carbon dioxide, 2% oxygen, and the 93% balance is argon.

 

[weldingscotty803]

ooooooooooo ok. didnt know that.
learn summat new on here everyday.
what will the oxygen do to improve the shielding gas?

 

[Paul.]

ooooooooooo ok. didnt know that.
learn summat new on here everyday.
what will the oxygen do to improve the shielding gas?

Oxygen lowers the surface tension of the molten weld pool, giving an effect known as wetting, this makes the pool more fluid, aids in penetration and reduces the height of the finished weld, one of the reasons why mig carried out with pure argon produces tall beads.

 

[weldingscotty803]

cheers for that paul. will remember that for when i can show off what i now know to the lads at work (not welders)