Custom spool generator

This is a customizable spool that can be used to generate a spool for printing. There are no checks when senseless settings are entered. Two sides are generated with enough room to be glued together. This was built to create a small filament roll for my cleaning filament stock that is far too little to store on an entire big filament roll.

Settings (with defaults shown) that can be set in the SCAD customizer are:

* spoolRadius=100 //The outer side radius
sideWidth=3; //The thickness of the sides
coreHoleRadius=25; //The radius of the inner hole
coreRadius=55; //The outer radius of the core
spoolWidth=55;// The width of the spool including the sides
filamentHoleRad=2; //The radius of the holes generated for threading through filament
edgeHoleCount=20; //Number of holes generated on the perimeter that can be used to anchor the filament.
indicator=1; //Indicator of volume. 0= off, 1=radial and volumetric steps
unit=1; //0=percent, 1=volume, 2=weight
SG=1.24; // The spec