3D CAD:
GT2 pulleys for focusing a camera lens

Contents:

1. Calculating number of teeth
2. CAD of 15 teeth pulley, part 1
3. CAD of 15 teeth pulley, part 2
4. CAD of 15 teeth pulley, part 3
5. CAD of 15 save and prepare to print, part 4
6. CAD of 174 teeth pulley, part 1
7. CAD of 174 teeth pulley, part 2
8. CAD of 174 teeth pulley, part 3
9. CAD of 174 save and prepare to print, part 4
10. CAD of 174 clean from support material, part 5
11. CAD of 174 new version, part 6
12. CAD of 174 slicing and printing, part 7
13. CAD of 12 and 15 teeth, new design, part 1
14. CAD of 12 and 15 teeth, printing, part 2
15. CAD of 180 teeth pulley, part 1
16. CAD of 180 teeth pulley, part 2
17. CAD of 180 teeth pulley, part 3
18. To be continued

Note:
I take no responsibility or liability for what are written here, you use the information at your own risk!

14, CAD of 12 and 15 teeth, printing, part 2:

I decided to print the 12 teeth pulley first to test if the axle hole fit the focus motor. I had over sized it by 0.1 mm.

12 teeth pulley, printing:

I setup Cura to ad a brim around the object. My earlier 15 teeth pulley got a very ugly bottom. It helps a lot, but what's it about the hole, it's inverted !

Pulling away the support and inspect the bottom of the pulley, no axle hole either. When looking closer in Cura I see that it's wrong already at that stadium. Must be something wrong with my drawing.

When I compare the new designed 12 teeth pulley with the old 15 teeth pulley I understand that a 12 teeth pulley has to small diameter to be a good choose.