is this argon?

[peterd51]

Hi,

I picked up a bottle at the market yesterday for £18, marked up as pub gas, 30% Co2 in N2...

but he said the bottle had been filled by someone he knows and it was now argon.

Couldn't find my argon/regulator adaptor yesterday, looked for 2 hours. Cleaned out my tool cabinet, and three shelves, found stuff I forgot I had! Checked again this morning and found it in a few seconds exactly where it should have been, in a small white box marked 'argon adaptor' in big blue letters!

Anyhow, I tried a few runs at different power settings and I'm not impressed, lots of spatter and horrible welds. The different 'look' to runs at the same power settings are down to different hand speeds, I think. I did try moving a bit quicker a couple of times.





The bottom two runs are with Co2 and are more 'normal'. I've never used argon before so the question is would it do this on mild steel with standard wire or is it more likely that this /is/ pub gas? If so I'll take it back next week, he's a long-established trader and he'll give me my money back.

Regards
Peter

 

[Luke]

Were you expecting it to be pure argon, or Ar/Co2/o2 like argoshield etc?

I'd say you've got CO2/N2 there, judging by the amount of spatter and the weld shape.

 

[peterd51]

Hi,

I expected pure argon. The guys sells all sorts of stuff from general household bits and pieces to 'engineering' stuff. he often has tools and the odd welder, etc, but he's not an expert in any of the gear. His 'contact' said argon and it might have been argoshield, but the result doesn't look anything like I'd expect it to be, even if it was pure argon.

It'll be going back next week-end.

Regards
Peter

 

[Bigjoe]

Peter i suspect it may be a pub beer gas cylinder,its either filled with co2/nitrogen or the guy has filled it with argon without the cylinder being purged empty first,so you might have co2/Ni/Ar mix

Either way it's not good i dont think

 

[malcolm]

The top few welds look a bit fizzy to me. The profile and holes in the welds would suggest a lack of shielding gas more than anything. Were you getting a good hiss from the gas?

Pure Argon isn't nice for mild steel MIG - you would expect the weld not to flow very nicely. Some photos on http://www.mig-welding.co.uk/welding-gas.htm

 

[peterd51]

Hi,

erm, I thought I'd replied to your last message earlier this afternoon...

thanks for the link, it looks like the mddle of my range is close to the bottom photo in your link (pure argon) but with much more spatter and a few holes in the runs.

I had the gas at 10 LPM and tried 20 LPM just in case.

I'll buzz the bottle back to him on Saturday.

Regards
Peter