Axis for reusing ESun spool

This axis permits to reuse an empty Esun spool.
(the reused spool shall be split by half to permit refilling - not easy to make it cleanly).
The resulting usable width is around 58 mm.

The standard diameter ot the Esun spool is around 89mm.
In order to accomodate Rosa filament refills, a ring adapter is also provided (93.6mm).
(didn't yet check with a Esun refill - with a little luck it would be also usable in this case)

The interior diameter of the axis is 47mm. You should check before printing that it is compatible with your spool support (in particular, custom ones).