GUYMASTER Release Notes
For version 4.0.4 as of July 29, 2013

1. This release corrects the calculation of the Slip length on polygonal pole. 
   The calculation of an the inside pole diameter, tip-to-tip was taken as: OD - 2t,
   when it should have been: OD - 2t/cos(theta), where:

   OD = Outside Diameter,  tip-to-tip;
   t = pole thickness; and
   theta = half the angle subtended by one side.

   The resulting fractional error (on the high side) in slip length is
   1/cos(theta)-1 as follows:

   Round Pole = 0
   18 sides   = 0.015
   12 sides   = 0.035
   8 sides   = 0.082

   If your aim was to make it 1.5 times the diameter, it would actually result in 
   1.48 times for an 18 sided pole, and 1.39 times for a 12 sided pole.