shielding gas. CO2 only or Ar-CO2 mix?

[Pavemen]

Is there really a preference? What is the difference in performance, cost, etc? Main use would be MIG/GMAW with a 135A Lincoln on mild steel.

[Proeliator]

75/25 co2/Ar is the way to go. Its the only thing I'll run anymore in my miller 210. If your running an underpowered machine the straight co2 can be nice with its penetration but otherwise stick with the mix.

[Brad]

C02 with that smaller machine. Cheaper and will get better penetration. I used C02 when I had my Miller 172 mig and it would weld anything

[DavidVanVorous]

Ar-CO2 "tends" to be cleaner (less splatter), iffen you want better fusion (better work than penetration) use flux core or flux core-gas...

D.

[Pavemen]

iffen you want better fusion (better work than penetration) use flux core or flux core-gas...

D.

please explain the difference 'better work than penetration'

[jasonmt]

please explain the difference 'better work than penetration'


I am going to have to take it as a typo with the intended phrase being "better WORD than penetration" with LOF and LOP being used interchangeably in industry.

[JTMcC]

I am going to have to take it as a typo with the intended phrase being "better WORD than penetration" with LOF and LOP being used interchangeably in industry.


Lack of fusion (LOF) (or using API terminology - IF or IFD, insufficient fussion or insufficient fussion due to cold lap) and insufficient penetration (IP) or insufficient penetration due to high low (IPD) are all well defined weld defects and the terms are not used interchangably in any work we do. Two seperate terms for two seperate conditions.


JTMcC.

[R290]

I think CO2 is cheaper in the long run. I use the 25/75 mix as it does not splatter as much, less cleanup before painting. As for penetration, it's not like your going to weld 1/4 plate or something. I have used both and just switch to a stick welder if I have to weld something heavy.

[Rory Bellows]

I use C25 (75% 25% mix). I like it alot although I have a 220 not 110 machine. CO2 is cheaper and provides deeper penetration but you run the slight possibility of freezing up your regualtor. If I were you I would get a decent size bottle(80cf) of mix because once you get into welding and fabbing you will probably step up to bigger machine down the road. You will always want more and it ain't that cheap!

BTW, when you go to get a bottle go to several places and check prices and fill prices. I dealt w/ an Airgas near me for awhile and always got a fill of 80cf tank for $18.xx. I always dealt with one guy as it appeared to me he was the only counterman. I go in there and see a new face and get a tank from the dock and loaded and go to pay and he tries to charge me $39.xx. According to new guy the other guy hasn't worked there in over a year. Funny I was just in there 5 weeks before and dealt w/him. Needles to say I now go to another distributor. Welding suppliers seem to screw the hobbyist welder and don't really care.

Guess my acetylene setup and tanks as well as an argon tank will go to the new distributor. I know it's a very small amount of sales but it adds up and I will bad mouth them to everyone I know.

Anyway, shop around and don't get the shaft. Can you tell I hate welding suppliers?

[Pavemen]

thanks for all the info. i already have a 20lb CO2 tank that use for 'trail air' so no tank needed, I jsut need to convert my mixed air reg to fit the CO2 valve. I can get fills for $25 picked up and delivered next day (dependent on the companies route though).

According the chart inside the cover, my welder is capable of welding 5/16" with fluxcore, but I was hoping that the CO2 will let me get up to 1/4". I am not a hardcore builder, so I don't expect to burn through tons of gas anyway.

It might splatter more, but whats a few minutes with a flapper wheel? besides, anti-splatter spray should help, right?

[DavidLH]

Jason, If you are in Modesto, try CH Williams on 11th St. They only charge $12 to exchange a 20 lb CO2.

[Pavemen]

Jason, If you are in Modesto, try CH Williams on 11th St. They only charge $12 to exchange a 20 lb CO2.

thanks, but i like my brushed alum tank that I own. i'll call to see if they do refills on private tanks

[nagalfar]

A 65/35 mix of Argon, and C02 is the best, it will give the best puddle stability, the gas has very little, and almost nothing to do with penetration, penetration is in your wire speed Vs. your amp setting and little else.. Gas(s) are a shield to remove all the oxygen (a oxidizer) from the area of the weld, different gasses can cause different effects on your puddle.. you can run a 65/35 mix at a lower psi.. you will notice things like a lot less spatter and dingleberrys when you use it..