Back to the subject of 20% Duty Cycle. According to the Miller website, the Duty Cycle is how many minutes of continuous use a welder can operate out of 10 minutes. They give an example of a 60% duty cycle saying it could operate at the full 300 Amps continuously for 6 minutes and then would require the remaining 4 minutes to cool down. The 60% would be the 6 minutes out of 10.
So for me at least, the 20% duty cycle will be fine. Most of my 20G sheet metal gets tacked at wire speed 4 and E on the Amps (A through J). At least I understand it a little more than I did.
