I have been trying out some of the various spool holder designs on Thingiverse and none of them completely worked very well. So I took the best features on what I tried so far and redesigned them to this form. I have been very happy with it so far and I no longer worry about kinks in the plastic filament anymore.
BTW...this design should allow you to mount 2 spools on your TOM at the same time. If that is something you would like to do.
1) Print all of the parts.
2) Tap the spindle into the hole provided in the bracket (I used a rubber mallet with no problems). You can glue or acetone-weld these two pieces if you would like (I used superglue) but that shouldn't be necessary.
3) Mount on tool and 1 kg spool as shown.
I would suggest printing this in ABS plastic with 100% infill for maximum strength. I am providing the scad files since I tweaked the spindle length +5 mm without testing it. The longer length should allow you to tap the spindle in to where it is flat to the opposite surface (it was still a little too short as of my last print) but there should be no problem if the spindle is just a little too long. Have fun!