Hardware neaded:

1 x M5x40mm screw

1 x m5 lock nut

2 x Ball Bearing 625 2RS 5x16x5

Installation of spool mount

Install the m5 lock nut into spool mount body.

then screw in the m5x40mm screw into the spool mount body

(the m5 locknut acts as the precision shim for the bearing in the spool to ride against)

install the spool mount to your 3D pen with a twist motion and lock it down with the tpu strap (or rubber band if you dont have tpu).

Putting your mini master spool together.

install the bearings in the spool bodies .

then add the spool hub (optionable -- i did not install it and it works fine without)

then feed a few mm of your filament into one of the 3 holes in spool 2 .

next screw spool 1 and spool 2 together .

next start winding your mini masterspool to load it up with filament.

when your done loading filament into your spool. mount your spool then lock the spool down with the spool lock .

finaly turn on your 3D pen/ select your filament and wait till it heats up then feed your filament into the 3d pen and start 3d printing.

Credits: https://www.printables.com/model/154670-3d-pen2-mini-master-spool-and-mount