Mig welding question

[Russell Ashley]

I'm using a Lincoln Weldpac 100 with .025 solid wire and 75/25 sheilding gas. One question that I don't remember seeing an answer to is how much pressure to run for the gas. I usually set mine to 20 psi and it seems good but I have also set it anywhere from 10 to 20 with also good results. I work in my garage with no or very little air movement so that isn't a problem. I am just curious about what you guys typically use as there seems to be a lot of experience and skill here on the forum.

[lakeroadster]

Shielding gas flow is expressed in units of CFH, cubic feet per hour.

The CFH recommended by filler metal manufacturers typically is based on deposition rates, welding positions, etc. In a production environment we typically use 35 - 40 cfh. However, depending on conditions, flow rates as low as 25 cfh are often acceptable.

Here is an excellent document from Lincoln Electric regarding GMAW welding (See page 67 for shielding gas flow rates): GMAW Welding Guide

[OKGMC4]

I usually set mine to 15psi. 10 works but I seem to get a cleaner weld with 15 and it feels like I really run through the gas at 20 with no perceptible difference in weld quality. This could all be wrong...I'm self taught in the garage, originally on a Hobart 110v and currently have a 110v Lincoln.

[dicer]

I use 25 to 30 cfm. And open the cylinder valve all the way.

[Dunenutt]

With a 110 unit euipped with a mini mig torch, 12-15 CFH should be fine with no breeze.