Encoder Knobs for Arduino | Keyed and Spring | Tuning, Potentiometer

Update April 23 2025

On the Nylon Set Screws

The threads don't necessarily hold strongly within the hole. I've had success with them though in a couple ways

• While the knob is off, turn the set screw to the minimum depth needed to hold the knob in place without sliding up while turning. Then install the knob and it should feel snug. Plan on a few attempts.
• Filaments' shrink characteristics vary. Some of my knobs hold the set screw in place perfectly. 

Update April 10 2025

Homemade Nylon Set Screws

Using 8-32 threaded Nylon rod I found it's easy to to affix the knob securely on the shaft without causing layer separation. 

Needed

• Nylon Threaded Rod 8-32 (11mm or longer)
• Three 8-32 thread nuts
• Hobby Knife
• Mini Hacksaw
• Vise
• Sharpie (fine)

How To

1. Cut off an 11mm length of Nylon threaded rod
2. Use the hobby knife to clean the end flat
3. Screw three 8-32 thread nuts onto the rod leaving 4mm exposed above
4. Tighten the nuts to secure the rod
5. Mark the center line, where the cut will take place, with the pen
6. With the saw carefully cut 2.5mm or so into the rod 

A set of knobs for use with standard Arduino encoder switches and potentiometers.

Two Main Types

• Keyed Mount 
• Spring Mount

Two Keyed Types

• Keyed High
• Keyed Low

Knob Types

• 58mm Tuning Knob with 18mm finger hole
• 25mm Encoder Knob 28mm Tall
• 25mm Potentiometer Knob 28mm Tall
• 25mm Encoder Knob 22mm Short
• 25mm Potentiometer Knob 22mm Short

Set Hole

• Each knob as a hole perpendicular to the mounting hole
• This is useful for aligning the keyed knobs to the encoder shaft
• It may also be useful with Nylon 8-32 set screws, but there's a danger of layer separation
• I recommend a small strip of aluminum foil over the shaft if needed to secure the knob
• Loctite or glue ought to work as well

Model Sources:

• https://www.tinkercad.com/things/8Fi7UUcHyEe-encoder-knob-v6-keyed
• https://www.tinkercad.com/things/eN2TN7qegpW-encoder-knob-v6-spring