Page 152 - The Complete Rigger’s Apprentice

Figure 5-12A–D. It’s much easier to buckle A than B
because the stiffness of a column under compression
A varies with the square of the unsupported length. B is
about one-half as long as A and thus about four times
stiffer. The unsupported lengths of C and D are the
same, but D is stiffer because the third hand pinching
near one end acts like mast partners, stiffening the
section above it and causing it to bend less easily, and
B higher up.

C

D Figure 5-12E–F. Here the pinching fingers simu-
late the effect of single and double spreaders. The
unsupported lengths are shorter, so a noodle—or
mast—of the same overall length is stiffer than it
would be with no spreaders.

E

F

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