I Just Bit the StewMac Bullet

I just spent $158.89 of my mad money on a set of ukulele fret files, a 3-in-1 fret crowning tool, and a fret rocker. I feel a little nauseous.

My concert ukulele is playing sharp down the fretboard, when tuned to pitch. Upon taking some measurements, I found that the string action is well over .4 mm at the 1st fret (as recommended by the GraphTech ukulele nut installation video.) So I want to lower the nut slots accordingly, to see if I can improve the intonation.

Of course once I do that, I will probably find buzzing, due to high frets, and need to do some spot leveling.

I have no intention of becoming a luthier, or working on other peoples stuff. I just want my $60.00 ukulele's intonation fixed.

Granted I could have bought a much better ukulele from a seller that sets them up for that much (or not much more.) But that wouldn't fix this one.

I could have spent less having a luthier set it up. However, the one I trust isn't taking new work right now, as he's so backlogged.

I could have bought cheaper tools, but that can be hit or miss. Also, I've spent more on stupider things.

I just felt like sharing. Wish me luck.

- Patrick

Good luck!

Be methodical. Focus on learning a process rather than just filing things. There is no magic fine motor skill required for this kind of work, it's just about being methodical, focusing on keeping things true and understanding what type of adjustment will have what type of result.

It does sound like your nut may be a little high. You should fix that first. But intonation (notes going sharp as you go down the board) is usually managed via setting the witness point on the saddle - a saddle blank starts out as a rectangle that's maybe 1/8" thick. You can file the top into a pointy shape, and by picking where the point is (towards the front or the back of the original rectangle) you can set the intonation of that string by changing it's effective length. You essentially have 1/8" of wiggle room to adjust the length. If a string gets sharp as you go up the fretboard, it needs to be "longer" - you accomplish that by setting the witness point further away, i.e. towards the tail of the instrument.

Welcome to the rabbit hole
:cheers:

Did the right thing Patrick. I should have bought the set many years ago. I could never justify the price point always thinking, how many more setups am I going to do. That was 5 or 6 setups ago . This way you have them and won't have to work nearly as hard or long using inferior torch tip cleaners and the likes. Please let us know how it works out for you.

I've done the same thing but bought Hosco files instead of StewMac. Have received the nut files but not the fret file and yet to have a go at the actual work.

dwizum said:

Good luck!

Be methodical. Focus on learning a process rather than just filing things. There is no magic fine motor skill required for this kind of work, it's just about being methodical, focusing on keeping things true and understanding what type of adjustment will have what type of result.

It does sound like your nut may be a little high. You should fix that first. But intonation (notes going sharp as you go down the board) is usually managed via setting the witness point on the saddle - a saddle blank starts out as a rectangle that's maybe 1/8" thick. You can file the top into a pointy shape, and by picking where the point is (towards the front or the back of the original rectangle) you can set the intonation of that string by changing it's effective length. You essentially have 1/8" of wiggle room to adjust the length. If a string gets sharp as you go up the fretboard, it needs to be "longer" - you accomplish that by setting the witness point further away, i.e. towards the tail of the instrument.

Click to expand...

Oh and as I measure the saddle is 4mm farther back than it should be. It's 189mm to the 12th fret, and 193mm from the 12th fret to the saddle. However, if the scale was too long I would think that would make it flat not sharp.

I thought about trying to add compensated to the saddle as it's not compensated, but thought I should fix the nut first.

Thank you.

Siv said:

I've done the same thing but bought Hosco files instead of StewMac. Have received the nut files but not the fret file and yet to have a go at the actual work.

Click to expand...

I debated between the Hosco and the StewMac, but decided on StewMac because they are supposed to have good customer service, and thought I should support them as I watch a lot of their videos.

Chewbacca said:

Oh and as I measure the saddle is 4mm farther back than it should be. It's 189mm to the 12th fret, and 193mm from the 12th fret to the saddle.

Click to expand...

That's because there's a default amount of compensation built in to every new instrument - the bridge is purposefully located slightly further back than the nominal scale length.

Intonation adjustments (by adjusting the saddle position) are to compensate for the string stretching as you push it down to the fretboard. That stretching action causes a note to go sharp, so you compensate/intonate by adjusting the saddle witness point backwards, making the length of the string longer, to drop the pitch back down to where it needs to be. As a result, Intonation adjustments are ALWAYS going to be longer than the nominal scale length, by an amount determined by the string thickness, material, and action. You never need a string's compensation to bring it shorter than the nominal length, only longer.

So, when building a new instrument, a builder chooses an amount to offset the saddle beyond the nominal scale length as a baseline compensation. That's the "extra" you're seeing between the 12th and the saddle compared to the 12th and the nut.

But each string will need a slightly different actual compensation amount. So, in addition to that baseline offset, you adjust the witness point on the saddle for each individual string to fine tune it. It's common for that initial offset to be in the range you're seeing, but each individual string will have a different "final" adjustment to get things perfect. On a re-entrant uke with plain strings, the G and A will usually be near the front of the saddle, the E will usually be somewhere near the middle, and the C will usually be somewhere near the back. Wound strings generally need less than plain.

dwizum said:

That's because there's a default amount of compensation built in to every new instrument - the bridge is purposefully located slightly further back than the nominal scale length.

Intonation adjustments (by adjusting the saddle position) are to compensate for the string stretching as you push it down to the fretboard. That stretching action causes a note to go sharp, so you compensate/intonate by adjusting the saddle witness point backwards, making the length of the string longer, to drop the pitch back down to where it needs to be. As a result, Intonation adjustments are ALWAYS going to be longer than the nominal scale length, by an amount determined by the string thickness, material, and action. You never need a string's compensation to bring it shorter than the nominal length, only longer.

So, when building a new instrument, a builder chooses an amount to offset the saddle beyond the nominal scale length as a baseline compensation. That's the "extra" you're seeing between the 12th and the saddle compared to the 12th and the nut.

But each string will need a slightly different actual compensation amount. So, in addition to that baseline offset, you adjust the witness point on the saddle for each individual string to fine tune it. It's common for that initial offset to be in the range you're seeing, but each individual string will have a different "final" adjustment to get things perfect. On a re-entrant uke with plain strings, the G and A will usually be near the front of the saddle, the E will usually be somewhere near the middle, and the C will usually be somewhere near the back. Wound strings generally need less than plain.

Click to expand...

Thanks you dwizum for enlightening me on the fact that the stretch from the 12th to the saddle is intentionally longer and why. I had been contemplating popping the bridge off and moving it forward, which is more than I really want to undertake. I will look at installing a compensated saddle next.

Also, thank you to all for the encouragement.

I'm kind of new to this so if any experienced builders/luthiers see something I have wrong, please correct me. I'm more experienced on setting up my bass guitars.

I also have a cheap ukulele in the same price range as yours. Mine's a Mitchell brand concert and I did several things to improve it's intonation and tone. The tools you bought are nice to have but they don't seem like they will adjust your intonation problem much. They're more for fixing buzzing from frets too high and not level. Check your frets with your rocker and see if you find any that are high. If you don't find any, don't bother filing and re-crowning. If only a few are high just spot level those and if a lot are high level the whole thing.

For the intonation issue, I'd imagine your saddle is the biggest culprit and is too high contributing to sharpness. Also, your nut slots probably need to be filed to the correct height & width. Most cheap ukuleles are going to be high on the saddle and nut. You can find some videos on youtube for doing a setup. HawaiiMusicSupply has some good setup videos on their channel.

I would start by measuring your string height at the 12th fret. You want to aim for around 2.5-3mm height (from bottom of string to the top of the fret). Most likely yours will be a little high as most cheap ukes are. If it is - loosen your strings, remove the saddle and sand the bottom of it on a very flat surface keeping the saddle perpendicular the whole time. Do a little at a time and keep re-installing it and checking the height (with strings at the correct tension) until you are in that height range. This might be all you need to do to get the intonation to an acceptable range.

Once the saddle is at the correct height check the nut. If you fret the string between the 2nd & 3rd fret, the string height over the 1st fret should be a pretty small gap (like a little bigger than a piece of paper). Most likely your slots are too high, like most cheap ukes are. With the correct size nut files for each slot you would file a little at a time and check until the instrument is playing how you like it. If you do file, make sure it's not flat at the top, but angled back toward the headstock. Follow the angle of how the strings would be at tension (from the tuner to nut). Make sure you're using an appropriate sized file for each slot. Too small and your strings will catch when tuning and too big isn't good either. Also don't go over board and file too much down or you will get buzzing strings.

From here your intonation will probably be much better. If it is still not exactly where you like it you could file in compensation to your saddle for each string until the octave is in tune (between open and the 12th fret). I haven't done this so I won't comment on how and I'd imagine you probably won't need it.

On my cheap uke, it had a plastic nut and saddle. Yours may also. I replaced both of those with bone and the tone improved quite a bit! I also replaced the strings which also added to the tone quality. Another thing that was bad on my cheapy uke was the fretboard plastic binding was too high. I filed it down a bit and dressed the fret ends which made it much more comfortable to play. Anyways, I hope some of this helps!

So far I've:

1. changed the strings to Martin Flurocarbon strings. I was using Aquila Nygut. I found the recommendation of trying different strings in a Elderly Instruments video. Also, I like the way they sound.
2. lowerd the nut slots to .040" (1.016mm) my frets were measuring around .030" (0.762mm). I stacked .040" (1.016mm) of feeler gauges and went slow with the StewMac nut files.
3. checked the frets with the rocker. Only the treble side on one fret seemed a wee bit high. However, it was way up in the tweedly end of the fretboard, so I can deal with that later.

Now it seems pretty well intonated. The action does seem low at around 0.079" (2mm.) It's not buzzing. If it starts I will either shim the saddle or get a new one.

Thanks everyone for the help.

- Patrick