Thumbwheel pots

[Mark Hammer]

Is there such a thing as a "good" or better-quality thumbwheel pot, the way that we evaluate better and worse regular potentiometers for smoothness and reliability?  Or is it the case that "better" simply means a physical installation and superstructure to make such pots behave more reliably? (e.g., precision slots to prevent lateral wiggling)

Just imagine how many controls one could fit into even a 1590A, if they were all PCB-mount thumbwheels, with no space required to get one's grubby fingers in there to twist a knob.

[willienillie]

Do you mean vertical trimmers?  I'm thinking of thumbwheel controls I've seen that were just regular pots with thumbwheel "knobs" on them.

[Mark Hammer]

I'm thinking of thumbwheel pots like one finds on Jazzmasters.

[willienillie]

Those are regular pots, though somewhat smaller than the standard 7/8" or 24mm, more like 5/8" or 16mm.  They are mounted at 90 degrees on a bracket, and then have thumbwheel type knobs on them.  The shaft diameter seems to be small on some of the vintage ones, I guess whatever fit the knobs they used.  Overall, that setup would take up more space in a pedal than regular 16mm Alphas.  Then there's the need to make a bracket, and the difficulty in cutting rectangular slots in the enclosure.

[anotherjim]

There were "regular" nut fastening metal bodied miniature pots with 3mm or 1/8" shafts. Used to see them a lot in Japanese portable stuff. I was excited to find some in a scrap CRO but only found low resistance like 100ohm values.

Bournes do an "audio" range of 9mm miniatures but plastic bodied and frail wire lugs  - no bigger than most trimmers. You could use 3mm shaft nylon toy/robot gears for wheels.
Mind you, I don't know where they get the "Audio" usage from - they only do linear taper! Duh!
https://www.bourns.com/docs/product-datasheets/3310.pdf

[deadastronaut]

https://components101.com/resistors/thumbwheel-potentiometer-5-terminal

[ElectricDruid]

Just imagine how many controls one could fit into even a 1590A, if they were all PCB-mount thumbwheels, with no space required to get one's grubby fingers in there to twist a knob.

...because what pedal-world needs now is *even greater* knob density?!? 

[Mark Hammer]

Point taken, Tom.
But seriously, sometimes there are controls one might want to include, but which aren't.  So, for instance, primary controls that one expects to be used regularly could be panel-mounted regular rotary types, with a shaft and a knob, and a few secondary occasionally-used controls could be thumbwheels at the side of the enclosure, where they don't distract, sand can't be stepped on.  I imagine fuzz bias is one example, but there are many others.

[davent]

There's a wide value range of thumbwheel trimmers you might be able to use for some application, will they be tall enough to protrude through an enclosure, do you really want to cut slots so that they can protrude through?

https://www.digikey.ca/en/products/filter/thumbwheel-potentiometers/77?s=N4IgjCBcoEwCxVAYygMwIYBsDOBTANCAPZQDaIcADDAGxgwgC6hADgC5QgDKbATgJYA7AOYgAvoQC0DaCBSQ%2BAVwLEyIAKxNWHSCHFixQA

dave

[Mark Hammer]

Those are really more like trimpots.  In fact, as I look down that page, I see some that I have actually bought in past AS trimpots.