SmartRap X and Y motor fishing line spool

For those of you who have D-shaped stepper motor shafts here's a rough attempt to resolve this issue (I have this problem too). The little holes on the outer flanges allow you to thread your line so that when you wind it, there is no slip. 3 to 4 windings should be more than enough. I will try to print this and see how it works. I have a hole and slot for a 2.5mm grub/set screw and nut as well. I have no idea how this will affect accuracy but the working diameter of the spool is 10mm, so I am hoping that it should not have that much of an effect, but I have no way of knowing how that affects the 1.8 degree steps on this print. The only alternative I can offer now is drinking straw superglued to the shaft and then you wind around that. The two halves of this spool should be superglued together before installing.