I have a Planner 44d diesal heater that I'm modifying the controller , it came with a little potentiometer that was kinda hard to turn .
I at first modified it by simply glueing a bigger knob on with The Amazing Goop adhesive and that made it much easier to turn but over time I realized I could improve it further by installing a bigger nicer pot .
Anyways I'm looking for a knob now , might put a better knob on my car stereo too.
First picture is the knob glued onto my Planner controller knob.
Then the rest of the pictures are what I've found so far for installing a new knob on a completely bigger potentiometer .
high quality rubber ergonomic potentiometer knob