Made this for my mini lathe. Brand new to 3D printing and first thing to design and print. Printed on PLA. 0.4mm nozzle. Used Ankermake M5. Infill was 30 or 40% using 3D Honeycomb for the fill pattern. Support needed. Not sure what other parameters are useful as I am still learning. Only on day three of 3D printing. 

V2 is just knob. V2.1 has line for indicator and indicator separately for different color. I have not printed my indicator yet so I am not sure exactly on fit but downsized by .01 mm on all sides to hopefully fit better and either be a tight fit or allow to be glued in.