Hello, I'm new to the forum and fairly new to electronics. I have some experience making LED flashlights and that's about it. I'd like to add a variable resistor to an LED flashlight which is in a small case. Thus normal pots will not work here as they are too large. So I'm getting some variable resistors (http://www.ebay.com/itm/371163925862?_trksid=p2057872.m2749.l2649&ssPageName=STRK:MEBIDX:IT) so the user can adjust the brightness of the light themselves, but without a screwdriver. Does anyone sell caps for these that will poke through a case? Is there a way to make a thick-walled cap to glue onto the screw?

Thanks.

 

I could swear I saw some, but that was 20 years ago. It would be "hardware" supplied by the manufacturer of the pots. However, if there has been little demand for that sort of hardware for 20 years, you won't find it in the retail realm. Another thing that seems relevant: most trim pots have expected lifetimes of about 200 operations.
http://www.bourns.com/products/potentiometers/trimpot-trimming-potentiometers-single-turn
http://www.mouser.com/ds/2/427/6-239988.pdf
http://www.mouser.com/ds/2/357/schneider_ZB4BD912-494062.pdf

While I was poking around, I saw some magnetic position sensors. They would seriously complicate the circuitry, but they might be much more reliable.

 

A pot like that may be hard to find. The "modern" solution is to use up and down push button switches and a microcontroller or a custom circuit.

 

Another thing that seems relevant: most trim pots have expected lifetimes of about 200 operations.

Wow, that's low. That explains why many of them in my radios are bad in about 4 years. Thanks for that important info.