How do I safely drill out spot welds to modify a factory fitting?

Use a center punch directly in the center of the spot weld dimple to keep your drill bit from walking. Use a specialized sharp spot-weld drill bit (a flat-faced bit with a centering point) running at slow speeds to cut cleanly through the top layer of sheet metal without drilling all the way through the second underlying piece of metal.

['Use a center punch directly in the center of the spot weld dimple to keep your drill bit from walking. Use a specialized sharp spot-weld drill bit (a flat-faced bit with a centering point) running at slow speeds to cut cleanly through the top layer of sheet metal without drilling all the way through the second underlying piece of metal.']

Stop if

• Use this as training guidance. The foreman, approved drawings, project specs, manufacturer installation instructions, employer safety policy, and AHJ/code requirements always control the final answer.

Steps

• Stop and verify the approved detail, manufacturer instructions, foreman direction, and project specs before touching it.
• Use a center punch directly in the center of the spot weld dimple to keep your drill bit from walking. Use a specialized sharp spot-weld drill bit (a flat-faced bit with a centering...

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