Screws were driven into the spiral lockseam

The spiral lockseam is the pipe's structural seam. Fasten through smooth barrel metal at the overlap, not through the multi-layer lockseam.

Stop if

• Stay away from the spiral lockseam track with your drill! Drive your screws into the smooth, flat metal skin of the pipe barrel so you don't unzip the structural seam.

Watch out

• Do not drill directly through the four-ply spiral lockseam track.

Check

• Find the factory spiral lock seam before drilling.
• Place screws evenly around smooth barrel skin.
• Inspect any seam that was hit for splitting or unzipping.
• Replace badly damaged pipe sections.
• Seal screw heads and the joint after mechanical fastening.

Steps

• Find the factory spiral lock seam before drilling.
• Place screws evenly around smooth barrel skin.
• Inspect any seam that was hit for splitting or unzipping.
• Replace badly damaged pipe sections.
• Seal screw heads and the joint after mechanical fastening.

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