Quote Originally Posted by performance View Post
If you are going to try to spray, use a 90/10 gas. People say you can spray with 75/25, but you have to have a higher voltage, which will indeed overheat your gun, and the arc will not be as stable, and the weld will not be as clean.
I know you're teaching people the correct technical way to do things but spray works perfectly well the way I've been doing it. Not the slightest hint of an unstable arc, the welds are clean and the gun doesn't overheat even at maximum duty cycle of the machine as long as I use a tapered tip. A standard or heavy duty tip will overheat the gun quickly because the tip absorbs a lot of the radiant heat. I also use #23 front end parts so the screw on nozzle is insulated further reducing heat transfer. You can hold my profax gun comfortably bare handed after maxing out the duty cycle on 1/2" steel.
With a heavy duty tip the gun will be smoking in a few minutes.

You got me started spraying and I'm very grateful for that. All the other details I worked out through experience.