Spool holder

# Spool holder (screwed shaft type)

## shaft-holder
Basic spool shaft holder for 20 mm aluminium frame.

## shaft-holder-2
Modified version for my 3D printer. Height from a aluminium frame surface to center of the shaft is larger than basic one.

## Spool-shaft-dd-ll
Screwed shaft to hang a spool.
- dd : Diameter of shaft at center in mm. Diameter on the end of the shaft is +5 mm of this value. Spool hole must be larger than this value.
- ll : Length of shaft in mm. Spool width must be smaller than this value.