Newly Built: fretted notes are all sharp...........nut adjustment?

[Michael Murray]

This is the first guitar I've made.

After tuning it to standard with all strings open (EADGBE)....

I apply finger to any fret and the tone is slightly sharp (ca. +20-40 cents).

Any ideas?

Thanks,
Michael

[Mark Swanson]

First thing is to make sure that your bridge is in the correct place. How did you measure for it? If you think the bridge is correctly placed, then put a capo on the first fret and see if it plays in tune then, and measure the intonation at the 13th fret instead of the 12th. This will eliminate the nut- if it plays right with a capo then your trouble is at the nut, and if the trouble is still there then it's at the bridge.

[Jason Rodgers]

Did you check the intonation at the 12th?

EDIT: Mark beat me to it, and with a better answer.

[Michael Murray]

Ugh....I followed your advice....... used capo. And the fretted tones are still sharp. Thus, Mark's suggestion is that the bridge is somehow offset.

This is not good news! When installing bridge, I measured and re-measured meticulously, but apparently did something incorrectly.

Now I'm wondering what to do!

I removed the saddle............... and the fretted tones are much closer to in-tune (within 10 cents on the meter).

Moving the bridge.......doesn't seem like a simple task. Maybe I can somehow move saddle closer to bridge pins?!?

Thanks for the feedback,
Michael

[Ryan Mazzocco]

that can be done. but first can you give us your measurements and explain to us exactly how you arrived at those numbers? You may have measured accurately, but were using the wrong numbers. there's a pretty common error that many first time builders make concerning the scale and placing the bridge, which I kind of suspect may be the problem here.

are you saying that you took the saddle out and with the string just between the nut and the pin it's still off about 10 cents? is it still sharp? or is it now flat?
I'd like to see a picture of your bridge if you can get one up.

[Barry Daniels]

Did you add compensation to the scale length when setting the bridge location?

[Michael Lewis]

Another often involved aspect is a high action, especially at the nut. The strings will go sharp as they are stretched to the fingerboard if the action is high.

The process of elimination will eventually point to the cause.

[Michael Murray]

OK, here's formula I used to position the bridge.
Measure distance from nut to 12th fret = a
Compensation amount = .10"
2a + c = length from nut to saddle at high E string.
2(12.67) + .10 = 25.46"

When I take saddle out, it's less out-of-tune, but all strings are about 10cents sharp, when any corresponding fret is depressed.

My action is high, so that indeed may be part of the cause.

[Peter Wilcox]

If your measurement from the bridge side of the nut to the middle of the 12th fret is 12.67", that would give a scale length of 25.34". Is that how you laid out the fret board? You can check out distances to other frets using a calculator such as this one: https://www.stewmac.com/FretCalculator

It looks like your strings might not be coming off the nut where it joins the fret board, but somewhere toward the middle of the nut, which could be causing the problem, in essence placing all the frets too close to the saddle. You need to ramp the nut slots down toward the tuners so the strings contact the nut where the fret board starts.

[Barry Daniels]

Yep, your nut is the problem. Also, you strings look a bit old. Also, what's up with the E string? There is no break angle. Are you wrapping the string windings up? They should go down.

[Alan Carruth]

What Peter said: in essence you've compensated the nut, only backwards. Even with it in the 'right' place you could well find note that were sharp at the first fret by as much as a five cents or more. They tend to go sharper above that. Nut compensation involves moving the nut forward; shortening the distance from the nut to the frets. This causes them to all play a bit flatter than they would have by the same amount in terms of cents, at least in theory. This gets the first fret note right. Then you shift the saddle back to get the 12th fret note right, and, again in theory, all the notes will be pretty close to in tune. "In theory there is no difference between theory and practice, but in practice there is". Still it helps.

[Ryan Mazzocco]

Okay, yes the nut is compensated backwards. But let's not forget that he has the same problem when playing with a capo. The nut is not involved in the equation at that point anymore. So it's both. I think the saddle is the bigger problem here since the nut can be replaced or filled and reslotted.

[Dan Smith]

I agree with all comments.
I'd make a new nut, and get the action down at the nut and saddle. Then recheck intonation before moving the saddle.
The guitar looks dandy, Michael!
Good luck,
Dan

[Michael Murray]

Super feedback. I suspected my nut shape was incorrect.....now it's confirmed.

Will re-shape and lower nut, lower saddle, then check intonation. I'm hoping to avoid moving saddle - that could be awkward! But will if I have to

Thanks very much!

M

[Peter Wilcox]

Michael - did you make the fret board? If so, what scale length did you use and how did you measure the fret positions?

[Bryan Bear]

Okay, yes the nut is compensated backwards. But let's not forget that he has the same problem when playing with a capo. The nut is not involved in the equation at that point anymore. So it's both. I think the saddle is the bigger problem here since the nut can be replaced or filled and reslotted.

The saddle very well may be an issue as well but I have a question about the capo test. Michael, when you capoed the first fret, did you tune the "open" (capoed at the the first fret notes) before you checked the fretted notes for sharp? I'm assuming you did but want to clarify. I also suspect that high action is a big contributor here; If you are able to play notes with the saddle removed without buzzing, I would expect the action with the saddle would be pretty high.

[Brian Evans]

I don't agree with setting bridge position by simply measuring - unless you have experience with your exact setup, string gauge and action height so you are basically exactly duplicating a proven installation. I would do this, in this order - first capo at first fret and set the intonation at the 13th fret correctly using a temporary saddle on the first and sixth strings, using corrected action height. In other words, get the thing in tune on those two strings with bits of wood resting on top of the existing bridge. This will tell you two things - first, it will give you an idea where the new saddle needs to be, and you will be able to judge if a new bridge needs to be made, if you can fill and rout a new saddle slot, make some offset saddle, etc. Also, it will tell you if the fret board is right. If it plays in tune at the capo'd 13th fret, it should play in tune all up and down the fretboard if the frets are in the right place. Second, I would make a new nut and start the setup process - set nut action height perfectly, establish and install the new saddle, set action height to 1/16" high E and 3/32" low E as a starting point, and see what you have. In other words, prove what you have "can" work, then make it work.

Higher than standard action will make any instrument designed "normally" play out of tune and be impossible to set up. Ditto odd string gauges, higher or lower tuning than normal, etc. If you take an instrument designed for regular E tuning and tune the 6th string down to C, for example, you might need to even go so far as to change the scale length, the string gauge, the compensation amount, to get it to play in tune properly - hence a real justification for the fan-fret design.