knob
thingiverse
I'm progressing with my project on Youmagine (https://www.youmagine.com/designs/knob-parametric). However, I have decided to halt further development due to Makerbot's (the parent company of Thingiverse) actions in applying for patents on open-source community works, which is a clear violation of intellectual property rights. As a protest, I will keep this file accessible but my future endeavors will be elsewhere. In fact, I recently replaced a broken knob with an OpenSCAD model (http://www.openbeamusa.com/blog/2014/5/22/stay-classy-makerbot).
With this file you will be able to print knob with your 3D printer. Click on the button and save the file on your computer to work, edit or customize your design. You can also find more 3D designs for printers on knob.