Hollow cylinder for filament holder made with a stand

This OpenScad module defines a hollow cylinder with parameters (outside, inside, length) that can be used for filament spooling.

__Using a retort stand__

It is always better to have the filament roll on top of the extruder. If you got a high ceiling or if you are moving your printer, then you need a portable solution. Together with a "chemistry stand" it will make a fine filament roll holder. Buy a retort stand, i.e. the kind that is used in chemistry labs. Yours could be made of:
* Two 1