The original pulley for the MakerBot is made from stacked lasercut wood. You have to glue it together, and it is fairly delicate in transit. This is sort of crappy, so I set out to see if it could be printed. The answer: yes. Yes, it can.
The technique I used was:
- Design the profile in QCad to get it nice and accurate (sorry, blender's 2D CAD sucks! Snapping is crucial)
- Import DXF into Blender
- Select all, join object
- 'Spin' around axis.
Print out and insert 608 skate bearing. You now have an idler pulley.