Solution to loose endpin jack

Gillian

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I know how to tighten the outside nut on the endpin jack and snug it up against the washer when it comes loose, but the problem is when the INSIDE nut becomes loose. I don' t have the tools to reach inside and tighten it, requiring a trip to the luthier to have it fixed.

When it happened again to one of my ukes, I went to the luthier and asked him what can be done to stop this from happening. He said "No problem. This is what you need." and brought out the endpin jack with three screws that cost all of $10. No more loose jack, no more twirling around of the wires inside.

Does anyone know the reason why pickup makers don't use this type of endpin jack in the first place?


IMG_0551.jpg
 
Hi, Campbell,

Good video. Thanks. I'm told this loose jack problem happens all the time. If it didn't, the guy wouldn't have had to make the video! ;-)

I'm sure that is how my luthier fixed the loose jacks also, but the problem was it was only a temporary fix. I don't know what I'm doing wrong to have the jacks repeatedly come loose. I try to not twist the amp cable around in the jack. I asked the luthier about putting a drop or two of Loc-tite on the inside nut but was told that was a no-no in case I ever wanted to remove the pickup.

With this three screw end pin jack fix, I hopefully won't have this trouble anymore!
 
I'm a little confused since I thought the jack is pulled until it's flush with the inside nut and then you tighten the outside nut so it doesn't move. You might have better luck posting in tech support. Good luck
 
Does anyone know the reason why pickup makers don't use this type of endpin jack in the first place?

When I was looking for a jack, I saw these. They seem like they'd be easier. But if you ever change out your jack, you'll have 3 holes because the flange is bigger than a standard sized jack/pin.
 
I'm a little confused since I thought the jack is pulled until it's flush with the inside nut and then you tighten the outside nut so it doesn't move. You might have better luck posting in tech support. Good luck
I am confused too.
 
There are two nuts on the main jack screw, one inside and one outside. When space between them is properly adjusted and snug, the jack is tight. When the inside nuts backs out, the pickup becomes loose and wiggly, allowing the pickup to twirl around inside. This would also cause the wires to twist around each other and maybe be damaged. It's no problem tightening the outside nut, but the video shows what has to be done to tighten the inside nut. What a pain.

The problem is this tightening is only a temporary fix. I wanted a permanent fix and the three screw endpin jack was the solution. Yes, I now have four holes in the end of my uke but I'd rather have that than twisted up pickup wires!
 
There are two nuts on the main jack screw, one inside and one outside. When space between them is properly adjusted and snug, the jack is tight. When the inside nuts backs out, the pickup becomes loose and wiggly, allowing the pickup to twirl around inside. This would also cause the wires to twist around each other and maybe be damaged. It's no problem tightening the outside nut, but the video shows what has to be done to tighten the inside nut. What a pain.

The problem is this tightening is only a temporary fix. I wanted a permanent fix and the three screw endpin jack was the solution. Yes, I now have four holes in the end of my uke but I'd rather have that than twisted up pickup wires!

I am not a luthier, but I've installed dozens of pickups with different jacks and endpin jacks and used a slightly different method than what happened on your instrument.

In my process, I bottom-out the inside nut (if I leave it on in the first place) by turning it all the way down to the jack assembly, and then put a drop of clear nail polish just ahead of the exposed thread, prior to insertion into the instrument. The jack has never moved in 20 yrs of doing this. Similarly, on the nut that is on the outside of the jack, on the outside of the guitar, also a small drop of clear nail polish on the threads AFTER the nut is snug, prevents it from coming loose. It takes a little more effort to remove, but otherwise zero maintenance.

Not saying your luthier did anything wrong, but should he modify his installation procedure slightly, his instruments will not come back for such maintenance as what happened with yours - but maybe that was his evil plan all along? LOL, Who knows? Maybe it's an excuse to see you again because he's fond of you? I dunno, I've seen crazier things.

Using the endpin jack with the screws is not an option for many folks who wish to molest their vintage instrument as little as possible, myself included. You also typically need to bore a hole that is at least 5/8" in diameter as opposed to the 3/8" or 1/2" hole for endpin jacks such as those used by Fishman, LR Baggs and Mi-Si. A smaller hole through the endblock is usually preferred.

However, YMMV. :shaka:
 
It's not so much the nut becoming loose but the tail block compressing after repeated unplugging of the lead. Many luthiers now use a plywood tail block because it is less likely to compress and allow this movement of the jack socket.
 
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I like your idea of a drop of nail polish, not Loc-tite, on the inside nut so it can't back out. That trick would probably have solved the problem.

Thanks!

I've also used a wrap of white teflon tape, like the kind used for faucet plumbing to wrap around the threads for a water-tight seal - also helps to hold the nut in the event of not having nail polish, but I caution you do NOT use Super Glue/Crazy Glue on the threads, you will never be able to loosen the nut without killing the instrument since you have no leverage against the rotation of the jack parts that are inside the instrument, unless the jack threads are 'keyed' with a whole that goes straight through like this:

This is the endpin jack as installed on my concert Flea, without the outer collar
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and to tighten, you insert a small screwdriver or similar into the keyed hole, so you have leverage for turning the nut, without the jack itself turning inside the instrument
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It's not so much the nut becoming loose but the tail block compressing after repeated unplugging of the lead. Many luthiers now use a plywood tail block because it is less likely compress and allow this movement of the jack socket.

Ahh. I had not thought of that. Never happened to me, but I can see how it would be a potential cause of the jack coming loose. Thanks for pointing that out.:)
 
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