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Apprentice answer

Why did my 45-degree offset travel piece fall short

2nd YearField Mods, Fittings, Offsets & TransitionsStandard Correction

A 45° offset travel piece follows the diagonal path, not the flat throw. Use the 45° multiplier, then subtract the fitting takeoffs before cutting the spool.

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Plain-English answer

For a basic 45° offset, the straight travel piece is not the same as the flat offset distance. The pipe or duct is moving along the diagonal, so the travel length is longer than the measured throw.

Use the 45° trade multiplier to get the centerline travel, then account for fitting center-to-face dimensions, collars, flanges, and any shop takeoff before cutting metal. The math gets the rough path; the actual fitting dimensions finish the cut.

Ask Foreman

I measured the offset at [measurement], but the first spool was cut to the flat throw and landed short. I recalculated the 45° travel path and fitting takeoffs. Do you want me to recut the travel piece to that layout?

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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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