Electric uke neck relief (truss rod adjustment)

Actually, I swapped the 14 to a 15 I had and the 18p to a 20w one I also had lying around. Both seem to fit ok in the nut slots (which is maybe a bit surprising already). The tensions match better to the 12 and 13, according to the calculator.

So, now I'm at 12.6-14.4 pounds tension and e-A-C#-F#. I'll wait for a day or so before I'll check the relief etc.
 
There are different styles of truss rods that have different limits, but if you're measuring as you go, and keeping it reasonable, you will probably not run into problems. Most styles make it clear when they reach their mechanical limits, the nut will stop turning because it's bottomed out, or it will thread itself right off the rod, depending on the style and which direction you're turning it. The danger is that it's often easy to break the rod before it gets to it's limit, but again - if you're measuring, and within typical relief values, don't worry too much. You just don't want to go off on a spree of cranking away at the rod without checking what it's doing!
 
Yeah, the nut hasn't given any signals so far. At least I know I have stripped my share of hex-bolt threads in my time and unless my communication with the rod is way off, I don't have a real reason to worry yet.
 
Alright, I got me a feeler gauge and tried to slide it straight in between. I reckon the relief less than 0.3 but more than 0.2 mm. The 0.25 mm strip probably didn't hit the string but the 0.3 mm did, I think. So I tightened the rod a bit and will check tomorrow.

What worries me a bit is that, at least before the tightening, the clearance at the first fret was less than 0.5 mm in all the other strings but the 4th. The three first ones were at about 0.3 mm.

Doesn't this suggest that the nut slots 1-3 are clearly too low? The tightening of the rod only makes the clearance smaller, doesn't it? The shape of the slots can't be the problem, since the strings are already thicker than the original ones.

So I'm probably going to need a new nut? Otherwise I'll have to buy a set of nut files and either try to hassle with super glue and baking powder or buy a clear nut. That should set me back almost as much as a professionally made nut. Or the shimming thing? I wonder if I'm gonna get it clean off and find suitable shimming material... And even then the clearance will differ with the 4th string.
 
Oh, and the relief measurement was taken at the 6th fret, which seemed to have the highest gap.

I wonder if it's possible to live with the max 0.3 mm clearance at the 1st fret, if I for example went a half step up in tuning... I'm again a bit worried about my finger strength (and not so much fingertips hurting).
 
Ok, now I measured again. The relief seems a bit smaller, somewhere in between 0.20-0.25mm. The first fret clearance is still around 0.3mm.

I think there was a little bit of buzz (the sitar-like kind?) on the open strings, so now I went a further half step up in tuning, to the fBbDG (so a half-step below standard high-G). This should still keep the strings under the 15 pounds, apart from the first one.

I probably don't dare tighten the rod anymore tomorrow to compensate for the tighter strings... I might have to live with the around 0.3mm relief, as long as the nut is as low as it is (?).

What's also a bit worrying or at least heretic is that all of the strings still sit completely in the nut slots. I don't have to estimate, if they're so thick that they're peeking out a third or half of the diameter - they really are completely below the top.
 
Technically, if the nut slots are too low, the strings will buzz on the first fret. Don't try to fix nut slots with truss rod adjustments. Get the truss rod adjusted for your target relief, then play open strings and adjust the nut slots if needed. Most people like nut slots to be pretty low, and the lower they are the less they'll impact intonation. If you're getting a little buzz on the first fret when playing open strings, a good way to proceed is to put a strip of plain old writing paper under the nut to raise it up a few thousandths. Add another strip and repeat until the buzzing stops. You then know the "minimum" nut slot depth you need.

It's OK to juggle lots of things to get where you want to go, but it's probably easiest to make the changes systematically, following a process, so you don't chase yourself in circles. Figure out what is most important to you (string gauge, tension/feel, tuning, etc) and then change one thing at a time until you get there. Check and adjust all settings in order each time you make a change. Otherwise you're kind of diving in the deep end of the pool without knowing how to swim.
 
Yeah, it makes sense to do things systematically and in isolation.

I was just thinking about some reverse engineer type of approach: now that I know that the nut slots are low, I could begin the setup with it in mind, taking it into account.

So I could set a bigger relief and higher action.

Granted, that probably is a suboptimal solution, since I've struggled with the hard-to-fret strings, mostly because of the high action.

It's just that it is an easier solution and not completely weird territory. I'd also have to buy Titebond to reglue the nut (?) and the paper strip too (?), if I were to remove the nut. I also have no idea, how hard and where the nut is glued. Luckily it doesn't sit inside the fretboard. I just hope the nut, if anything, is all I break in the process.

Maybe some brave day I'll take out my hobby knife, hammer and a piece of wood... And the next day end up at the luthier's :D.

Also granted is that a piece of paper is immensely cheaper than a new nut. A new nut will be more than I paid for the instrument. Not that I'm complaining of luthier prices; I'm well aware of why the price of such an instrument is so low and that of a local luthier so high.
 
It's really, really hard to "fix" a low nut by adjusting relief and action. It's like a giant triangle - you have to raise the action REALLY high at the 12th fret in order to get a very small change at the 1st fret. It's not really going to work.

Most nuts are glued in with a tiny dot of glue. Generally, you can pop them loose with a very gentle tap from the side - I use a wood dowel and a small deadblow hammer. Just a tiny tap and pop - the nut is loose. No need to buy special glue to put it back, you can you a tiny dot of plain elmer's school glue. Or you can leave it unglued, the only real risk is that it'll move around or fall out when you change strings - I tend to leave nuts unglued for the first few weeks of a new instrument's life until I know everything is settled in.

Another option is the baking soda trick - pack some baking soda in the low slot(s) and add a tiny drop of thin CA. Then re-file.

Or just buy a new precut nut! Generally, when I have a nut that's too low, I do the paper shim technique in order to determine a safe minimum height. Then I cut a new nut at whatever that final height is.
 
Yeah, true. That's what the problem is and has been with all the setups I've tried: the action has to stay too high.

The intonation is now about 2.0-2.1mm at the 12th fret, and there's a slight buzz when strummed hard.

I don't suppose I'll find a precut nut for a high-a (or high-g for that matter) tuned electric uke. I'll gather my courage for the nut tapping or take it to the shop. Thanks for the help, dwizum!
 
Alright, so I gathered my courage and took the nut off! The strings could be left in the tuning machines by loosening them enough to slide them down the side of the fretboard. I then worked all around the nut with a hobby knife, and I'm glad I did. I think there was still some lacquer on the tresholds between the nut and fretboard. The nut was also lining with the fretboard so perfectly that I suppose it was never removed since it was assembled at the factory and lacquered.

In addition, there were uneven spots of glue here and there on the nut and perhaps also some tape (?). I think the tape might have been responsible for lifting the 4th string side... Anyway, it didn't need any tapping force after carefully finding out, where the glue/tape was still holding the nut in place.

What was a bit strange was that the nut was sitting on top of a quite a) thin and b) uneven slice of the end of the fretboard. Right under the fretboard is, I think, a gap in the headstock wood, routed for the truss rod nut, so if one was to break the thin slice that's left of the fretboard, on which the nut is sitting, I don't know how the situation could be remedied without replacing the entire fretboard (which is separate from the neck).

Anyway, the surface of the fretboard slice was fairly straight, save the minor differences in the color and finish (?) at the bottom, which was a bit baffling. I would imagine it being optimal that the thing is carved (or sawn/sanded, whatever) and then left without any finish? Perhaps it's a matter of saving time in the process (and automating it?): 1) carve nut slot, 2) glue nut in place, 3) route/sand final shape of the neck/headstock/nut, 4) lacquer, instead of 1) carve nut slot, 2) mask the contact surfaces, 3) route/sand final shape of the neck/headstock, 3) lacquer, 4) remove masking, 5) glue nut in place, 6) route/sand final shape of the nut.

Anyhow, I didn't dare touch so much of the surface, it being so thin and uneven in colour even that I was afraid I'd chase myself through it finding a uniform and measurably even look. I just scratched off the parts that I thought were traces of the said tape or other obvious goo with the blunt side of my hobby knife.

Then I cut a piece of drawing paper by the edges of the nut. The paper was a bit thicker and less uniform (more porous and laminated) than regular printer paper, but at the end it still wasn't thick enough. After two retunings and measurings, I ended up adding two pieces of printer paper underneath too.

I have white, non-toxic PVA glue, but I didn't dare glue the nut on yet; it does slide if you want to, but I have to see how it holds in playing.

Anyway, the original problem seems now gone! I think the unevenness of the nut slot heights also got better, but the biggest relief is the fact that I can now lower the action to a very smooth level. The action is about 1.5mm at the 12th fret. It makes a world of difference! I don't find steel strings hard to handle at all anymore :).

It is still tuned to A#6/Gm7/"high F", with the 12-15-20w-13, but I bought me a .022 plain string that I am planning to use as a G3 and then build a set of 13-18p-22-14, tuning it to dGBE ("high d"). I have to see, if the strings finally start to rise or stick in the nut slots, or if they will still work with thin strings, tuned to high g...
 
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