TIL about jib extension limits but I'm confused on the calculations.

Wren Allen · 2026-03-01T11:56:46.444987+00:00

My trainer went over jib extensions with me this morning. He said the capacity drops fast with each section, but the math behind it seems off to me. How do you guys figure out the safe load when the jib is fully extended?

johnl876mo ago

Something a lot of charts don't show clearly is how much the ground condition changes the math (soft dirt versus solid concrete). That moment load gets way bigger if the outriggers sink even a little. Always check the plate for the fully extended chart, but honestly, if the numbers seem close, just don't do it. The capacity really does fall off a cliff past a certain point.

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sageadams6mo ago

Hear johnl87 mention soft dirt and I got really worried. The moment load jumps a crazy amount if the ground isn't solid. Makes that 'falling off a cliff' thing way too real.

3

sageadams6mo ago

Thought it was off until I ran the numbers myself.

1