With four quick lifts, raising the load only a few inches, a rigger can confirm:
a) The load's estimated weight
b) The load's approximate center-of-gravity (CG)
c) The approximate load at each pick point
Find the approximate weight and the location of the CG of the load in the diagram. Answers provided below.
Happy trails to all my crane and rigging friends, Mike Parnell
P.S. This article was originally published in The Professional Rigger Newsletter - Find CG by Test Lift.