Apprentice answer

How do I install TDC/TDF corners without smashing them or bending the flange

1st YearDuct Assembly, Seams & JointsCheck first

Use a dedicated TDC corner tool or a drift pin (alignment punch) to align the corner bolt holes perfectly before inserting the bolt. * Never try to smash a misaligned corner home using a framing hammer-you will bend the gasket seal area, creating a permanent high-pressure air leak.

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Plain-English answer

Field checklist

Use a dedicated TDC corner tool or a drift pin (alignment punch) to align the corner bolt holes perfectly before inserting the bolt. * Never try to smash a misaligned corner home using...

Ask Foreman

Hey boss, I’m checking duct assembly: How do I install TDC/TDF corners without smashing them or bending the flange? I found the likely issue and want to verify the next step before I lock it in. Do you want me to adjust it now or check the drawing/detail first?

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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