I have an existing piece of equipment that has a potentiometer on the side that controls the speed of the machine. I would like to be able to set the speed, then put some kind of cover over the pot to stop anyone from idly twiddling it. I imagine this will take the form of some kind of dome nut.
Does anyone know of anything like what I've described, and where I might be able to get it?
I am not able to remove the pot in this equipment, or move it inside the case.
Peter
Just make a cover and fit it
Years ago they were not all that uncommon. But may be harder to find nowadays.
The pot nut was either like a nylock nut or had an end like a drill chuck collet that you tighten a locknut on. The nut usually had an external threaded barrel that you screw a cap onto that looked pretty similar to an old style panel indicator lamp lens.
The pot would have a short stubby spindle, usually with a screwdriver slot in the end.
Various manufacturers made *that sort of thing* - but the only name I can remember is Bulgin.
Nowadays; you're likely to have to try all the pot manufacturers.
** The device you want is called a "potentiometer shaft lock" - consisting of two parts, a nut with collet that replaces the pot mounting nut and a locking nut that clamps the shaft. Obviously, the lock must suit the type of pot involved.
AFAIK, they are unobtanium nowadays, though I see *one* on Ebay that suits a 3/8 inch pot thread with 1/4 inch shaft.
I think your only option is to fabricate and fit a cover over the control.
.... Phil
There's ten turn dial pot knobs with a lock, they're not cheap.
example:
Grant.
get a small metal or plastic jar with a screw on lid.
drill a 10mm hole in the lid
remove the knob and nut, fit the lid over the neck of the pot, add a pop-rivet, or small screw to stop the lid from spinning, replace the nut and knob, adjust, fit the jar.
Have something to add? Share your thoughts — no account required.
Ask the community — no account required