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Apprentice Q&A · #096

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

2nd YearField ModsRED · Stop / Verify

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.

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Plain-English answer

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.

Field checklist

Ask Foreman

Hey boss, I’m on field mods and need verification before I touch this: How do I safely drill out spot welds to modify a factory fitting? Do you want me to stop here and check the approved detail, submittal, or inspector/manufacturer requirement first?

Open Ask Foreman

Verify before acting

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.

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