Multi-turn pot

[mojoe]

Is a multi-turn pot like what's in the picture available? I've looked on Mouser, but didn't find anything in the same form factor. I measured about 9.6 mm across the width (top to bottom in the picture). A 5 or 10 turn would be ideal.

[Nominal Animal]

Your best bet in such confined space is to use an O-ring (or even a rubber band) to the actual multiturn pot, and just have a mechanical shaft holder in place of the current pot.  This used to be a common solution a few decades ago with radios and large adjustable air-gap capacitors.

[MarkF]

Mouser has the Bourns 3856 Series 3 3/4 turn pots. 
The body is 19mm diameter though and the pin pitch is 0.25 in. with a 0.25 in. shaft.



About the smallest I could find on a quick search.

[Fraser]

I know of no ‘COTS’ multi turn potentiometer in that small form factor. In my experience such would normally be a custom part, likely based upon a miniature multi turn trimpot topology.

In situations where a miniature multi turn potentiometer is required, I have seen multi turn trim pots used. A small brass shaft is attached to the brass trimpot adjuster. This is not something I would wish to do as it seems like a “hack” but I have seen it used on commercial equipment to good effect. I have no idea of the trimpot life expectancy if regularly adjusted.

There is a temperature calibrator that I own that uses this “adapted trimpot” approach and it has been reliable. Picture attached.

I think the trimpots used in this ‘hack’ are the version with a finger grip adjuster. Picture attached.

Fraser

[Fraser]

Others have faced this same challenge and I found a 3D printable adapter to add a knob shaft to a standard multi turn trimpot.

https://www.printables.com/model/1085661-multiturn-trimpot-knob

[mikerj]

I have no idea of the trimpot life expectancy if regularly adjusted.

The Bourns ten turn trimmers are only rated for a life of 200 cycles.