Is argon sootier than co2

[gordonendersby]

Dear all,

Ive just got a 10litre cylinder of Argon/Co2 5%, regulator and adapter for my Clarke 135TE. I previously used disposable Co2 for the short time Ive had the mig.

The Argon seems to leave more brown soot than the Co2.
Ive tried changing the flow from as low as 5lpm to 20lpm.

The weld looks ok for my level of learning.
It just seems to need more cleaning up than the Co2.

Does that sound right or do you think theres something wrong somewhere?

Thanks

Gordon

 

[GrahamGKD]

Hi Gordon,
As far as I know the brown soot is usually a problem with gas coverage – is your shroud clear of spatter?

 

[pedrobedro]

The brown soot is oxides from the metal melting, don't worry about it.

 

[gordonendersby]

Graham, Yes shroud is clear. I invested in a pair of welpers and some tip dip.
Also made sure the tip dip didnt block the gas.

pedrobedro, I thought that was the point of the shielding gas. I wasnt getting nearly as much residue with the co2.

One thing that occurred to me after writing the initial post is the steel was covered in grease from the stockist. I wiped it down with rag then wire brushed it on the bench grinder. Do you think there may be still some grease causing it?

Thanks

Gordon

 

[GrahamGKD]

I suggest you try cleaning a test piece of the metal with some white spirit and drying it before welding and see what effect that has.

 

[shenion]

Also try making sure your torch is nearer to vertical. A low angle will bring in air.

 

[gordonendersby]

I had tried changing the angle so it was closer to vertical but it didnt make a lot of difference on that attempt.

Today Ive had a better result and reduced the soot but still a little there.
I ground the steel plate with a flap wheel and wiped down with panel wipe.
I increased the gap to about 1cm from the tip to the weld.
I ran the gas at 10lpm also slowed my travel and zig zagged it a bit.
So a bit more gas available over the weld.

As time went by the soot reduced some more till I had a lot less.
A lot happier with the result but dont know why it got better over the length of the practice session.

Does the gas improve after you first crack it open or is just my welding getting better and more consistent?
Im posting in the learning section with some photo's to see what people think of my progress so far.

Thanks

Gordon

 

[Lawnmowerboy]

I would have thought it's just technique improving?

 

[gordonendersby]

Have a look at my new post in the learning section and see what you think.
Id be glad of any comments.
http://www.mig-welding.co.uk/forum/showthread.php?t=37395

Gordon