[Hammack_Welding]

On 1/4" plate and .035 wire I run in the area of 21 Volts and 360 18 Volts is not near enough heat for material that thick.

 

[Hammack_Welding]

320 is still to low of a wire speed for 21 volts.... Turn it up another 40 IPM 360 would be about right for 21 volts as I mentioned earlier. I'm not trying to be a smart butt, but without pictures we are all shooting in the dark. Post some pics, and we can diagnose the problem, but we can't tell you much without seeing the welds. Have you had anyone else try and run the welder? The simplest way to find out if it is the machine or operator is have a "qualified" person give it a shot and see what happens.