Rotary Volume Knob

This is a project mash up. I have been wanting to add a rotary volume knob to my PC because I don’t like the windows way. This will use a rotary phone mechanism and an arduino to give me volume selections of 10%-90% and a 0% silent setting. I saw a rotary knob build on Adafruit an a bluetooth cell phone dialer on Hackaday and the idea was born.

NOS (new old stock) Western Electric rotary mechanism (circa: 1981 ±)
Test fit #2 was a success at 109 mm diameter

The final part will have a rounded body similar to the old phones. I also want it to hold some of my most used desktop items, a Sharpie, #11 Hobby Knife and my Rotring Rollerball. Waiting on a roll of black PETG for the first full body test print.

First print of full top
Pleased with aesthetics and proportion

It is not often that I design something in F360 and don’t make changes after printing. I like the way this came out. The large radius edge gives a period correct feel and the size and spacing of the holes is good. I am waiting on another spool of black PETG to arrive (48 hrs). I will print the base on Sunday and see if that needs any tweaking.

The only modifications I know will happen are the ones to mount the arduino and do cable management. I need to have a physical prototype to get an idea of how I am going to do that. I suspect it will just be some mounting holes on a built up portion of the back side of the base. A hole suitable for a grommet will also need to be added for the USB cable. Felt feet will have to be glued on as the bottom of the base is the side flat down on the printer bed.

Author: Joe