mono jack nut thread pitch

jessenator

jessenator

Well-known member
I've encountered two different pitches (and outer hex diameters) in monojacks, so I'm wondering if anyone has tried these. I'm guessing—since they aren't listed like Neutrik and Switchcraft are—they do not fit the Lumberg KLBM shrouded jacks, yeah? I.e. they aren't compatible with M9x0.75?

lovemyswitches.com

Dress Nut and O-Ring Set for 1/4" Jacks

Protect your pedal with this dress nut and o-ring set for Switchcraft 1/4" jacks. The hex nut hides the bushing so all you see is a smooth, perfect finish.
lovemyswitches.com lovemyswitches.com

Then my follow-up, if that's the case, does anyone know of that style of dress nut that will fit that M9 standard? I like the look and design of the concave vs convex/domed dress nuts.
 
I guess I didn't specify. I'm looking for one that's M9x0.75 but thanks for looking for it.

I almost exclusively use the KLBM in my projects, and going to use a "panel" (PCB…) mount jack for some projects.
 
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So this has still been eating at me. I haven't been able to locate a source of the concave, shrouded dress nut, like the Switchcraft W07, in M9x0.75.

I want to pivot the conversation towards what it would take to commission something like this, and if anyone would be interested in a kind of group buy to cover it, for those interested. Math says they cannot be re-tapped, since

So apparently I've only tried it one way (M9 nut onto 3/8-32 jack), but never the other way---must've thought it would just not work and not to try. I just tried it and a 3/8-32 nut threads onto these M9x0.75. Like, very well. And barring a significant amount of torque (more than is likely needed for our purposes), these should thread on. Similar situation where 1/4" (6.35mm) pot nuts will fit 6mm shafts, but not the other way around?

So that's neat™
 
I went thru something similar to this. My 1590b top jack builds use four nuts to space the jacks around the inner lip of the bottom cover, and I like to use the cheap enclosed jacks, some of which have m9 fasteners and others use 3/8 unf. Depending on where I got them, the same nuts would fit on some jacks and not others. The M9 jacks have slightly smaller threading surfaces, which is why 3/8-32 fit on them.

I finally figured out the right combo of tayda 40 cent jacks and small bear switchcraft 17 cent nuts.
 
Took a look around. Hard to find an equivalent. But...if one wants to go for a more industrial look, these are available:

gavantools.com

M9 x 0.75 Thin Hex Jam Right hand Thread Nuts 10 Pcs Stainless Steel

M9 x 0.75 thin hex jam right hand thread nut Approximate thickness: 4 mm The thickness may vary depending on the production lot number. Quantity: 10 Pcs Material: 304 stainless steel Please note that the product picture is for reference purposes only and may not depict the exact item and size...
gavantools.com gavantools.com

I'll keep scoping it out.
 
Boy howdy: I gotta say. That ain't an easy thread to find.

Pretty sure the standard metric fine thread pitch in a M9 is 1mm. This 0.75mm pitch is easy to find, but the majority of what's available isnt...eh...dressy.

Maybe another approach? Think outside the box? Like, maybe stupid thick fender washers. Or something.
 
Boss does something with almost the exact same jack for the remote switch on the Angry Driver (and possibly others)

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But I'm thinking since I tested the 3/8-32 and it fit, maybe tracking down the M9 isn't as critical? Maybe there are long term considerations?
 
Chinesium threads. It's just another form of planned obsolescence.
I have a filtered water dispenser that is thread M13 with a super fine pitch. Shipped with a big washer and a 2 thread nut made out of soda cans. I now have a $200 Delta dispenser to install because that nut puked it's threads out at 14 months and I can't find another one. I forget the pitch. I finally found a tech drawing of the faucet in Chinese and McMaster has zero results. Bump back and shoulder=I'm only crawling under that sink one more time.
 
Sometimes threads match up. Another example is M5 and 10-32. They are close enough that they interchange one way, like here. If the 3/8 unef nuts thread on and cinch up, then there's no reason they wouldn't work
 
Hmm.

Well, just read the bit about the 3/8 actually fitting. I'll be damned.

Yeah, 1/32"= 0.79mm. with the slop involved I could see that fitting.

The problem you're likely to encounter is treads stripping from too much torque. You're probably riding the ragged edge there, and the potential for the jack threads coming loose means they could be subjected to more stress over time, eventually stripping out one or the other.

BUT...There are ways to shore up the connection. A little Teflon tape *might* fill the gaps a bit better and provide adequate lubrication to get the nut snug. Alternatively, you could also use a dab of red loctite on the threads. Then whoever wants to pull out the jacks will need to break out a torch to do so.

The good news is that the connection doesn't need to be watertight, it's just gotta be solid.

Other alternatives:

Bellevlille washers. They're sort of conical, meant to compress and add a little spring pressure to the nut. They come in decorative styles sometimes, take up more real estate than a standard washer, and there ain't no problem with using a 3/8" washer on a 9mm shaft.
 
As long as most of the threading surface is maintained, they are doing their job enough to maintain a secure connection. Maybe the threads have less friction than the correct size, but you could run a simple experiment to see how much torque you would need to apply to strip the threads, and compare it to your standard torque figures. For example when I tighten my nutz I use a regular chrome socket from a tool kit and only go hand tight. If you are putting a 3/8 ratchet on that thang with any amount of force you're already applying much more torque than is necessary for a secure fit with one of deez nuts, and you can build a scenario rather quickly whether the force to strip the nutz is greater than any real world application under normal circumstances (ie how you normally tighten them)
 
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