No thingiverse também existem muitos desenhos de knobs que o pessoal daqui pode usar nos projetos:
https://www.thingiverse.com/thing:669272
(https://cdn.thingiverse.com/renders/12/2f/3f/af/37/Mike_GuitarKnob_v1_preview_featured.jpg)
https://www.thingiverse.com/thing:54024
(https://cdn.thingiverse.com/renders/f8/57/f9/52/b6/Knobs3_preview_featured.jpg)
https://www.thingiverse.com/thing:1072393
(https://cdn.thingiverse.com/renders/6b/07/18/06/ff/knob_preview_featured.jpg)
https://www.thingiverse.com/thing:4828448
(https://cdn.thingiverse.com/assets/a7/0f/7a/e6/6c/featured_preview_Vintage-Knob-C-examples.jpg)
https://www.thingiverse.com/thing:6167996
(https://cdn.thingiverse.com/assets/ce/43/5a/27/60/featured_preview_3cb626aa-154e-4657-98f6-7bb0a02213b4.png)
https://www.thingiverse.com/thing:4807288
(https://cdn.thingiverse.com/assets/5c/51/db/3f/aa/featured_preview_Vintage-Knob-A2-Sizes.jpg)
https://www.thingiverse.com/thing:1060323
(https://cdn.thingiverse.com/renders/a2/19/d0/5b/58/IMG_20151008_065212_preview_featured.jpg)
https://www.thingiverse.com/thing:2786480
(https://cdn.thingiverse.com/renders/3e/0b/ff/85/43/6d422a6b9c7019213fbc82e73f6e4630_preview_featured.jpg)