1HP VCO Eurorack module

So I’ve decided to boldly go where no synth-diyer has gone before: try to fit a VCO into a 1 hp module. I know it’s theoretically possible within the specifications of eurorack; there exists 3.5mm jack inputs that have a total package width of less than 5mm. There are also slide potentiometers I could use that are 5mm in width, but to save the already limited panel space I have, I would prefer if I could use a rotary potentiometer.
Which brings me to my problem and my question for this community: Where exactly can I find a rotary potentiometer whose entire package has a width less than 5mm? I myself am currently scouring the web looking for one, but unfortunately all the big name electronics sites tend to have their potentiometers sorted by shaft diameter, with no filter or sorting option for package width… which means I have to open each part’s datasheet and search through that to find it.
any help would be greatly appreciated!

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you could use something like this: TOP-UP INDUSTRY CORP. -- 10P1HF-B
You need only a small slot on the frontpanel for the disc.

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This is a good idea, but not exactly what I’m looking for. Personally if I had to make a compromise I would rather use a slide potentiometer and have less features on my module than this disc potentiometer, because I’m not a fan of the tactile feel of it. But I’ll consider it for other tiny modules I’m thinking of making in the future, perhaps a very slim mixer or something

Use a trimmer then glue something onto the adjustment screw(pencil lead? 3D print?)? I think you’ll be hard pushed to find a vertical pot with less width than 5mm. Have you looked for right angle PCB pots?

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What about something like this?

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Also found this slide one if you prefer it, it’s 5mmx4mm on the sides that seem to meet your requirements:

https://www.digikey.com/en/products/detail/tt-electronics-bi/PSM050S-10B10KB/9997286

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I’ll probably go for one of those, and make a real version of intellijel’s 2012 april fool’s joke, the 1hp tricore VCO Intellijel - uVCO 1HP tricore vco !!!!! - MOD WIGGLER
But I do want to have <5mm rotary potentiometers. They don’t seem to exist yet, but they will one day if I have anything to say about it.
From this video on the construction of a potentiometer, it seems that all I would need is some serious fine metalworking and model making skills to make this happen. Potentiometers - How They Work, Disassembly and Exploration - YouTube
A difficult project to undertake, but certainly not an impossible one. I’ll let you know of my progress if I ever get around to it. and if anyone else already has the kind of equipment and skills to make their own custom tiny pots and wants to beat me to it, do let me know how you get on!

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What about this one?

Or this one

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what do you mean? those are all wider than 5mm

My apologies, I thought they said they were 5mm x7mm tall… I must’ve read that wrong.
I’m just trying to help find some. I’m sure they exist.

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Yeah, it probably means the shaft is 5mm diameter. There are plenty of potentiometers with smaller shaft diameters than 5mm, but a rotary potentiometer whose entire package can be fit in a width of 5mm? I’ve been looking for a while and I haven’t seen one. It’s entirely possible they don’t exist yet. I could use a potentiometer with a <5mm shaft and a >5mm total package width, and the potentiometer would stick out the sides on the back of the module’s panel. This wouldn’t be a huge deal for adding it to a regular modular system in a lot of cases- there’s usually a few millimeters of space between the components/circuit board and the edge of the panel on regular modules, so this 1hp module could be fit next to those and it would probably be fine. But you wouldn’t be able to put two 1hp modules next to each other, or put a 1hp module next to a module that happens to not have as much tolerance in it’s behind-panel space.

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What about these little guys? They are 6.4mm wide but maybe you can file away the 0.7mm on each side :wink:

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