Page 156 - The Complete Rigger’s Apprentice

A Lyle Hess Cutter to the top of the mast would describe an angle of less
No designer I know is better at this rig gestalt process than 7.5 degrees, which is too narrow. Given that he
than Lyle Hess. Analyzing his rigs is like analyzing a wanted neither to widen the boat nor shorten the
well-written piece of prose: You try to express things mast, the only way to obtain an adequate staying
differently and discover that the author has already angle was to install a spreader, in this case 20 feet
1
found the best way. above deck (Figure 5-15). This spreader is 4 ⁄2 feet
Let’s go through a Hess design and see how the long, and the length of the mast above it is about
principles discussed above can find expression in an 19 feet. With the aid of a diagram, or of that tradi-
actual rig. tional rigger’s tool, the electronic calculator, we can
When he designed the 30-foot cutter Syrinx, determine that the angle at the top of the mast is
Lyle Hess drew in a mast extending 38-plus feet now a healthy 13.3 degrees (see Chapter 6 for the
above deck, but the half-beam was only about how-to of trigonometric functions).
5 feet (Figure 5-14). Given those dimensions, a wire If we now construct a stress diagram that
includes the spreader, which functions as a com-
pression member (Figure 5-16), we see that the
Figure 5-14.
wire’s condition has been eased at the expense of the
mast, which now must withstand not only a down-
ward force from the wire without buckling, but also
a sideways thrust from the spreader. The solution to

Figure 5-15. Figure 5-16.

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