Silicagel container for filament

(
December 2018 update:
1/ Fillet added to remove sharp bottom edge
2/ Travel mini-soap dispenser settings added (works really handy, actually)
3/ freecad-file: measurement bug fixes.
)

Rechargable silicagel is very useful for keeping the filament dry. This silicagel-container was designed for fitting inside the filament spool, to keep the filament dry whilst stored in a bag (eg, many filaments comes in a zip-lock bag). Its height can be adjusted to convenient length for most filament r