wood.john•1mo agoTop Commenter

Update: Had a weird lift in Tacoma last month with a 250 ton crawler

We were setting a big HVAC unit on a roof, and the signalman, a guy named Carl who's been doing this for 40 years, kept telling me to ignore the load chart's fine print on boom deflection. He said, 'In the rain on this ground, you add ten percent to your radius in your head before you even look at the chart.' It worked perfectly, but I'd never heard that rule before. Has anyone else been given a specific percentage adjustment trick for wet sites?

2 comments

2 Comments

hayden5871mo ago

That "add ten percent to your radius" thing is smart. A buddy of mine was on a site after a thaw, real soft ground. His old foreman told him to treat the crane like it was on a five degree list even when it was level, just in his head for the pick. Basically meant he wouldn't get within 80% of the chart. Saved their bacon when one outrigger settled way more than expected. Those old guys have rules for everything.

rodriguez.jordan1mo ago

Sounds like overkill to me. Most charts already have a safety factor built in, so adding more just kills your efficiency. If the ground is that bad, you should be using mats or not setting up there at all. Relying on imaginary lists instead of proper site prep seems like a weird workaround.