Welding regulator settings.

[tauruck]

Guys, I need advice on what you think is optimal on the L/min (CFH) setting for mig?. I know it's dependant on conditions like welding indoors or out etc. Thanks in advance.

[Captthundarr]

Try the Miller welding or Lincoln welding web sites. They should give you some baselines.

[tallguy]

For short-arc welding, which I've done a lot of (typically using solid
.035 dia or .045 dia wire), I used about 40 cfh (cubic ft/hr).  But you
could experiment with less, until you have problems with porosity.  I
suggest you experiment on scrap material, rather than your race
vehicle.  Too much gas flow could be bad, because it tends to suck
in air from the sides, due to the venturi effect.  Please remember, also,
that air movement such as wind will affect your shielding-gas coverage. 
And contamination, such as grease or paint, will absolutely destroy your
weld.  When it comes to welding, "cleanliness is next to godliness."

tallguy

[kiwi belly tank]

Yeah, 40 should be plenty inside Mike, any more than that & you're wasting it & 035 wire is ideal for the typical 1/8" crap we weld. Anything beyond 3/8" you might want to go to 045. I run CO2 because of the lower cost & lay down quality welds. I had a friend here the other day that swore by argon mix until he made a pass with my welder on CO2.
  Sid.

[tauruck]

Sid, I also used that mix but the CO2 seems better. The post is a few months old and I did have too much gas going back then.

My gas has lasted way longer since I changed the setting.

[Sumner]

I used straight CO2 on my first mig, which was a Miller 110 v.  I felt that the C02 allowed better penetration which was important with the 110v welder.

Carbon Dioxide (CO2) is the most common of the reactive gases used in MIG welding and the only one that can be used in its pure form without the addition of an inert gas. CO2 is also the least expensive of the common shielding gases, making an attractive choice when material costs are the main priority. Pure CO2 provides very deep weld penetration, which is useful for welding thick material; however, it also produces a less stable arc and more spatter than when it is mixed with other gases. It is also limited to only the short circuit process

http://www.bernardwelds.com/mig-welding-shielding-gas-basics-p152080#.UrYw-ieLWSo

I feel that the mixed gas makes nicer looking welds ...

For many companies, including those that place an emphasis on weld quality, appearance and reducing post-weld clean up, a mixture of between 75 – 95 percent Argon and 5 – 25 percent CO2 will provide a more desirablecombination of arc stability, puddle control and reduced spatter than pure CO2.

http://www.bernardwelds.com/mig-welding-shielding-gas-basics-p152080#.UrYw-ieLWSo

... and since my newer Miller is 220 v. and has higher amperage settings I can get the penetration I want and the welds look nicer,

Sum