How do I avoid the over-bitten pittsburgh seam (crushing the pocket)

Plain-English answer

You are hand-seaming a custom offset transition fitting. You use your tongs to lock down the starting lip of the Pittsburgh pocket, but you squeeze the handles so violently that you crush the receiving pocket channel completely closed, making it impossible to slide the matching flange sheet home.

Hand seamers are for setting spatial angles, not for crushing mechanical pockets. Adjust the internal set-screw stop on the handles of your seamers to physically block the jaws from closing past the single-ply metal thickness, allowing you to set the. The likely recovery is to check the tool setup, correct the prep or technique if it is within your assignment, and bring the journeyman or foreman clean information before the work creates rework overhead.

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

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