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Talk to me about potentiometers (and also switches)

I am making progress on a mod project to convert my late 90s MIJ Ibanez SR800 to fully passive. I've ordered parts, and now that some have arrived, I'm realizing that they are the wrong size. In researching this I've also come across some other factors that I hadn't initially considered when selecting them. I've tried searching a few of the usual places (Allparts, Mouser, Sweetwater, Amazon) but not having much luck finding what I need.

Potentiometer specs that I am seeking:
-500k value preferred, but willing to go 250K if every other condition is satisfied
-narrow/mini/8mm or 5/16" bushing diameter
-10mm or 3/8" bushing length (I think this is called a 'long shaft'?)
-just regular old pots, no push/pull or stacked concentric. These are for volume (x2) and tone (x1)
-not too loose feeling - I have pots on another bass that turn themselves if you breathe on them or look at them funny and it annoys me. They're next up for replacement after this project.
-I don't need boutique quality and would prefer not to spend more than $10 per pot, but obviously a cheapo piece of crap pot isn't worth the time and effort.
-Linear? Audio? I am uncertain!
-I would really like to avoid any drilling/widening of the holes on this bass

I did find a set of four (I only need 3, but pots are cheap enough that an extra one or two isn't a problem) on Amazon from a Chinese manufacturer I don't recognize called "gazechimp". I've no idea if these are at all reliable, and furthermore, this is a set of two linear and two audio pots. I've done some reading on this site and there are differences of opinion on which type is better for each purpose though the opinions tend to skew in the direction that audio is better for volume and linear better for tone.

Also on Amazon by an unrecognized Chinese manufacturer is this set of 5 audio 500k pots that appear to fit my specifications.

How much of a risk am I taking by getting cheap pots from a random Chinese manufacturer? I know a lot of these factories in Shenzhen make the exact same component to sell to different distributors who each put their own name on them, but I've had inconsistent results buying stuff like this from Amazon in recent years. These are cheap enough that I'm a little leery of the quality. Can I find pots that meet my specs from a more reliable/reputable manufacturer?

One last question about switches. I am planning to use a DPDT switch to do a series/parallel switch. I know I can get this in a push/pull pot but I've got four holes to fill, and I'd rather not leave any empty so a discrete switch is my preference. It will be going in the same size hole as the pots, however switches don't appear to come in that exact diameter. I will probably have to get a 1/4" diameter bushing and wrap a couple layers of tape around it, or something like that. The problem is that I am having trouble finding one with a long enough bushing to fit in the hole. I ordered this one but it's too short. And most of the listings on Amazon don't specify the length of the bushing. Is there somewhere else I can look for these that will be more specific? Is it even possible to make a toggle switch with a shaft that narrow and long?
 
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You may want to have a look here:
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or here:
Potentiometers - Best Bass Gear

I’ve actually had very good luck finding most of the things I need at Mouser, Allied or Digi-Key but you have to get good at using their filters.

Many people seem to prefer linear pots for volume and log for tone but it’s pretty subjective. It’s usually best to experiment and choose what you like.

No-name Chinesium pots might work out fine for you for a while but I don’t know if I’d trust them for a really long service life. If they’re cheap enough, go for it!

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I would stick with CTS, Bournes, Dunlop, Fender or Alpha Pots

I'm familiar with all those names at this point. As far as I can tell CTS does not make pots with a narrow shaft, but alpha does. Not sure about Bourns, Dunlop, Fender.

I am probably overthinking the linear vs audio pot thing.

I'm still unsure about how to address the switch situation. I may just put in a push/pull pot and not connect the pot to anything if I can't find a long & narrow toggle.
 
I'm familiar with all those names at this point. As far as I can tell CTS does not make pots with a narrow shaft, but alpha does. Not sure about Bourns, Dunlop, Fender.

I am probably overthinking the linear vs audio pot thing.

I'm still unsure about how to address the switch situation. I may just put in a push/pull pot and not connect the pot to anything if I can't find a long & narrow toggle.
You want one long and one narrow mini toggle switch? If so I can help with that tomorrow. Going to try and get some sleep right now.
 
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As far as I can tell CTS does not make pots with a narrow shaft
They do.

The CTS factory is located in Taiwan, ideally situated to ship 6.35mm/M9 shaft pots to the USA and 6mm/M8 pots to the rest of the world. Along with 'full size' pots, they make mini pots; the Series 270/275.

This Mouser datasheet will let you order pots with your exact requirements.

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You want one long and one narrow mini toggle switch? If so I can help with that tomorrow. Going to try and get some sleep right now.

No - I just need one toggle.

However, I took another measurement tonight and I think the one I have will work, just in a different hole than the one I originally planned to put it in. The curved top of the bass means that the holes aren't all exactly the same depth.

There are also two holes that currently house stacked concentric pots. Those holes are slightly larger (9mm vs 8mm) but not large enough to accommodate a standard size bushing. I will probably need to fashion some sort of bushing to add around it. Surgical tubing, wood dowel with a hole drilled through the middle, or...?
 
Rubber O-rings make fine bushings. Learned that trick from Audere.

Surgical Tubing sounds like an idea but you might need washers that help cover the hole plus if you make the tubing ever so slightly taller than the body when you tighten the nut it will squeeze it out for a tighter fit in the hole.

Both fine suggestions. I'll need to go to my local hardware store anyway to get a nut and washer so I'll see what they have. Another possibility is using a 9mm dowel and drilling out the center to make a donut, if I don't find tubing or rings in the right size.

Thank you!
 
mouser.com and guitarelectronics.com are my go-to. Guitarelectronics.com also has a lot of good wiring info. Mouser is great, but sometimes a bit too much, and you have to pay attention to what you're ordering. I accidentally ordered a capacitor for 600V instead of normal. Thing was as big as my thumb. So double check the spec sheet

Of course now I'm tempted to put that capacitor in a bass for no other reason than to be ridiculous.
 
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Another possibility is using a 9mm dowel and drilling out the center to make a donut, if I don't find tubing or rings in the right size.
It might be tough to bore out a dowel without splitting the remaining “donut”. You might have better luck cutting a slice off the end of a piece of brass or aluminum tubing of the right outside and inside diameters.
 
It might be tough to bore out a dowel without splitting the remaining “donut”. You might have better luck cutting a slice off the end of a piece of brass or aluminum tubing of the right outside and inside diameters.

My dad has a wood shop in his house and feels confident he can do it if the dowell is hard wood, but the metal tubing is also a good idea. Sounds like I have a few options. Thank you!
 
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I found some plastic tubing today at the hardware store - the inner diameter fits the switch perfectly, but it's ever so slightly too wide on the outer diameter to fit. I think I'll try to sand or shave it down a bit, if this works it's definitely the cheapest option - a foot of the tubing cost me $0.27 and I'm only going to use maybe a 1/4” inch of it.

Pots and pickups are supposed to arrive today so I'll see how well those fit in their holes. I measured the pickup cavities and it looks like it will be tight - hoping I don't have to shave out any of that.

Here's what I ended up getting for pots. A pair of these as well as a matching pair of linears, I'll probably do the volumes with linear pots and the tone with one of the audio pots.

I'll have to start a drawer of miscellaneous electronics parts once I finish this project...
 
I found some plastic tubing today at the hardware store - the inner diameter fits the switch perfectly, but it's ever so slightly too wide on the outer diameter to fit. I think I'll try to sand or shave it down a bit, if this works it's definitely the cheapest option - a foot of the tubing cost me $0.27 and I'm only going to use maybe a 1/4” inch of it.

Pots and pickups are supposed to arrive today so I'll see how well those fit in their holes. I measured the pickup cavities and it looks like it will be tight - hoping I don't have to shave out any of that.

Here's what I ended up getting for pots. A pair of these as well as a matching pair of linears, I'll probably do the volumes with linear pots and the tone with one of the audio pots.

I'll have to start a drawer of miscellaneous electronics parts once I finish this project...
Cool but your link does not work
 
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