Intonation issue on the first 4 or 5 frets

[thecigarcritic]

Hello- linked below is a video of a new ukulele. The intonation is pretty bad at the first 4 or 5 frets, but will play true at the 12 fret.
I filed down the nut as much as I can, but still have issues.
I'm trying to send it back, but I would really prefer to fix it instead of deal with this company. They don't have the best customer service. It was shipped with D'adarrio Nyltech, which feel pretty thick and tight.

 

[Woody Ukepicker]

Not that bad. And the difference is quite the same on each string which should not be a problem at all.
Try again when not pressing so hard on the string.

 

[Graham Greenbag]

If you have set-up the Uke well then I

 

[anthonyg]

It's definitely the nut at fault. Intonation going sharp over the first few frets but getting better up the neck and at the 12th fret is definitely a fault in nut placement.
The nut is too far away from the frets. If the intonation was going flat over the first few strings but getting better up the neck the the nut would be too close to the frets.

You could remove the nut and then file down the end of the fretboard but there is an easier way. If you have a matchstick at hand then place the matchstick on the fretboard, up against the nut and under the strings. I do just this with 1.3mm and 1.5mm Allen keys.

Is the problem now fixed?

 

[Graham Greenbag]

Hit by the software bug during editing so here’s the revision:

If you have set-up the Uke well then I’d expect the Uke to be accurate at the first five frets. It might be that the nut is slightly further forward than it should be - it’s unusual but it very occasionally happens. I’d tune the Uke to be right at the second fret (so up a tone) and then check out the rest of the scale.

I don’t expect that your finger pressure was stretching the strings. but a light touch next to the fret is best.

If the Uke was cheap and you have the skill then diy changes are worth doing, but if it was expensive then it’s almost always better to return the instrument.

Good luck.

Edit. Matches and Allen Keys have been mentioned above, I had in mind a straightened paper clip.

 

[John Colter]

I recently bought a very inexpensive soprano (twenty-two pounds inc. VAT & p&p). It played badly out of tune. The distance from the nut to the first fret was almost 2mm too long. I fitted it with a zero fret. I like zero frets, so for me that's a win-win.

John Colter

 

[UkeStuff]

I had a ukulele that I was sent to review and the fretboard was mis-cut. The first fret was about 1/4" longer than it should have been, which I first checked by comparing it to other ukuleles and then looking at scale calculators (e.g. StewMac has one). Since it was a $25 ukulele, I used a coping saw and solved the problem.

If the frets are right, and you have the harmonics at the 12th (and maybe the 7th), then it is probably action at the nut combined with stretchy material strings. You're probably pulling the strings out of tune as you play.

 

[thecigarcritic]

Thank you all for the replies and the helpful feedback. To answer some questions, although I may be pressing down hard in the video for effect, when I'm playing I'm not pressing the frets hard at all and it's still very noticeably out of tune. This is my 3rd uke and the only one where this is a problem. Oddly enough, this is the most expensive one of the lot even though it wasn't too pricey and certainly catered more to beginners.
The action is super low right now, so I'm thinking the fretboard is just a hair off. When the open strings are perfectly in tune (using an app instead of the cheap tuner) even the 12th fret is up to 20 cents sharp. I'm not comfortable doing this work myself. Any guesstimate on what a luthier might charge?

https://photos.app.goo.gl/myUajkLXqj1Tshuz8

https://photos.app.goo.gl/LmnWSnEeesqNHcwj6

 

[badhabits]

how come the tuner needle isn't moving when plucking the open strings? is it working properly? are you sure it's in tune to begin with?

 

[anthonyg]

Thank you all for the replies and the helpful feedback. To answer some questions, although I may be pressing down hard in the video for effect, when I'm playing I'm not pressing the frets hard at all and it's still very noticeably out of tune. This is my 3rd uke and the only one where this is a problem. Oddly enough, this is the most expensive one of the lot even though it wasn't too pricey and certainly catered more to beginners.
The action is super low right now, so I'm thinking the fretboard is just a hair off. When the open strings are perfectly in tune (using an app instead of the cheap tuner) even the 12th fret is up to 20 cents sharp. I'm not comfortable doing this work myself. Any guesstimate on what a luthier might charge?

https://photos.app.goo.gl/myUajkLXqj1Tshuz8

https://photos.app.goo.gl/LmnWSnEeesqNHcwj6

Placing a matchstick/allen key/paperclip on the fretboard, up against the inside surface of the nut and under the strings doesn't require any skill and is completely reversible. Give it a try and you will then know for sure if this hypothesis is right or wrong. You can then show this to any luthier and they will know exactly what to do.

 

[anthonyg]

https://photos.app.goo.gl/myUajkLXqj1Tshuz8

https://photos.app.goo.gl/LmnWSnEeesqNHcwj6

OK, I had a look at your photo's and the first question is, where did the 15.5" scale length come from? If it really is a 15.5" scale length and the nut to 1st fret measurement is correct, then my hypothesis is wrong.
However I doubt very much that the 15.5" scale is right. It's MUCH more likely to be 15" flat. The issue here is "Nominal" scale length vs "actual" scale length.
When talking about the frets, we are talking nominal scale length. When talking about saddle placement we are talking actual scale length, which is nominal scale length + saddle compensation, so, actual scale length is longer than nominal scale length yet the only figures used to work out fret placement in the stewmac fret position calculator is nominal scale length.
Nominal scale length is twice the distance from inside the nut to the centre of the 12th fret, BUT, if the nut is positioned long then the distance you come up with will also be long.
It gets complicated.

 

[thecigarcritic]

Thanks Anthony. Complicated indeed. I'm way out of my league here.
I got the scale length from the company's website. I lucked out with two nice ukes from this company, but I pressed my luck a but too far on my 3rd

 

[anthonyg]

Thanks Anthony. Complicated indeed. I'm way out of my league here.
I got the scale length from the company's website. I lucked out with two nice ukes from this company, but I pressed my luck a but too far on my 3rd

Well if the website say's it's 15.5" then it probably is. Personally I always measure just to make sure, plus when you measure the scale length you can compare what your measurement is to what the specification is to observe any error that may be there.
It's probably the measurement with the vernier callipers that's wrong. These measurements to the middle of the fret are very difficult to make.

None the less. Find yourself a matchstick or a small allen key if you have one and place it as I described and just see what happens.

EDIT: Looking again. If you have measured inside surface of the nut to inside edge of the fret then this is wrong. It's inside the nut to centre of the fret which isn't so easy to do accurately.