If I lose arc in the middle of a long cut, how do I restart where it left off?

Well, this is what the “Disable Torch” checkbox is for! Here is what you would do:

• Click the “Disable Torch” check-box under the Torch button so it has a check mark.
• Find the M5 just before the beginning of the cut you were on when it stopped and click on it.
• Click the “Run From Line” button. The machine should start to run except that the torch will not fire.
• Now quickly move your mouse over the “Disable Torch” checkbox, and when the torch is just about where the cut stopped, click the check-box. The torch should now fire and resume the cut.