How do I fix a piece of rectangular duct if it's knocked together out of square?

Lay the duct on a flat floor. Measure diagonally from corner to corner in an 'X' pattern. If the measurements aren't equal, apply controlled body weight or mechanical pressure to the long diagonal corners while tapping the Pittsburgh seam with a mallet to reset the metal's memory back into square.

["Lay the duct on a flat floor. Measure diagonally from corner to corner in an 'X' pattern. If the measurements aren't equal, apply controlled body weight or mechanical pressure to the long diagonal corners while tapping the Pittsburgh seam with a mallet to reset the metal's memory back into square."]

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

• Lay the duct on a flat floor. Measure diagonally from corner to corner in an 'X' pattern. If the measurements aren't equal, apply controlled body weight or mechanical pressure to the...

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