Pulley for my wooden rostock variation. It's made for 0.5mm Dyneema.
You can insert 2 M3 nuts to fix this pulley on your stepper.
The inner hole for the Dyneema Line goes curved arround the hole for the stepper.
The initial idea did not work. To less windings.
I use it now with only two windings arround it and not going trough the middle hole. Works great with the right tension.
In normal use, you can only travel 300-400mm