How to Start and Stop in Arc Welding

In arc welding, you'll eventually run out of an electrode before you are finished with the job. You must know how to start the weld again where you stopped, without making excessive strike marks. Strike marks are defects in the welding and can cause cracks.

Difficulty: Moderately Challenging

Instructions

1. Stop welding when the electrode runs out. Change the electrode so you can start welding again. When you start to weld, it's called "strike the arc" because you are striking the metal with the weld.

2. Start the weld again by "striking the arc" beyond the previous stopping point. Make sure you "strike the arc" in the same direction that you will be welding in so it can be melted and covered up with the new bead.

3. Weld back up to the end of the bead, where it stopped when you ran out of electrode. Pick up the bead at the original stopping point, then reverse directions to start moving the bead forward and cover your strike mark. Be sure you are welding in the same traveling direction as you originally welded.

4. Melt the strike mark out by applying the bead to the strike mark, where you started. This will melt the original strike mark and prevent cracks. Continue with the welding bead to the end of the plate. When you reach the end of the plate, backtrack by about ¼ inch to fill in the crater at the end of the weld. The welding technique of backtracking stops cracks from forming at the end of the weld and makes the weld stronger.