What type of glue would you use on set potentiometer screws on a PCB?
Loctite is often used. However there are many types. In general you hear people talk about blue, green and red (242, 290, and 271). Blue prevents inadvertent movement due to vibration and such. With moderate force the pot could be turned. Green is stronger, usually you need to apply a little heat before it can be turned. Red requires a lot of heat and would probably destroy the pot.