Casting
To take safety precautions first
silicone
The Ratio of silicone that I used is: (A)10 silicone : (B)1 hardener
Tips:
Try to calculate the volume of the product first before mixing in an amount of silicone so that you do not waste it.
Epoxy
I used CMB Kemapoxy 150
Now I need to redo the same previous processes for the Cap of potentiometer
So, Let's start :)
Roland file for Arm here
Roland files for CAP of POT here