What's the trick to seating a stubborn Pittsburgh seam on a large rectangular fitting?

Start at one end. Use your hand seamers or a raw hide mallet to gently start the flange into the pocket. Work your way down the line incrementally, tapping the male edge fully home into the pocket before you start flattening down the locking lip. If you hammer the lip flat prematurely at the start, the rest of the run will bind out of alignment.

['Start at one end. Use your hand seamers or a raw hide mallet to gently start the flange into the pocket. Work your way down the line incrementally, tapping the male edge fully home into the pocket before you start flattening down the locking lip. If you hammer the lip flat prematurely at the start, the rest of the run will bind out of alignment.']

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

• Start at one end. Use your hand seamers or a raw hide mallet to gently start the flange into the pocket. Work your way down the line incrementally, tapping the male edge fully home...

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