Nut shelf (headstock) not square to fretboard

[jonnycat]

Hello all,

I am replacing the nut in an electric guitar, and after removing the old nut I find that that the nut shelf (on the headstock) is not square with the top of the fretboard. Instead, the angle formed is obtuse, as you can see from the attached drawing.

This leads to the problem that the new nut "rocks" back and forth; either it sets on the edge of the fretboard, or on the neck. Since it needs to be (lightly) glued onto the neck, this would create a gap between the nut and the fretboard.

I have considered trying to sand the nut to fit, but I have no precise way to hold it at the proper angle (this is a pre-slotted nut, and I don't have a lot of slop to work with, maybe 0.008"). I have also thought of maybe using some type of wood putty or cyano to fill the gap on the neck, and then filing it down.

What would your solution be to this problem?

[charles Tauber]

EDIT:

I misread the drawing. I'd file the nut to match the angle of the head veneer, as John described.

[John Arnold]

Since you don't have enough height to trim the nut to fit, I would add wood to the bottom of the nut, then angle it to fit. I use a small vise and a coarse file to shape nuts to fit. Sandpaper glued to a flat block can be used to flatten the bottom. On older Martins, the bottom surface is roughly parallel with the peghead face, so the bottom of the nut must be angled about 15 degrees.

[jonnycat]

Originally Posted by charles Tauber

Me? I'd probably trim the end of the fingerboard with a chisel so that it is square. Failing that, I'd shape the nut to have a matching obtuse angle. Forming the angle isn't difficult. I'd use a sanding shooting board - it's easy to make one for the purpose - with shims under one edge of the nut to get the right angle. Layers of masking tape will work sufficiently for the shims.

Thanks Charles. I wish I had the skill to get near the end of the fingerboard like that, it is an elegant idea. Thanks for the suggestion for the shooting board, I think I can make a small one just for this purpose.

Originally Posted by John Arnold

Since you don't have enough height to trim the nut to fit, I would add wood to the bottom of the nut, then angle it to fit. I use a small vise and a coarse file to shape nuts to fit. Sandpaper glued to a flat block can be used to flatten the bottom. On older Martins, the bottom surface is roughly parallel with the peghead face, so the bottom of the nut must be angled about 15 degrees.

Thanks John. That sounds like it would be a good solution for me, now I just have to come up with some thin strips of wood.

[phavriluk]

A thought: Be interesting to know how the original nut (was this one a replacement or OEM?) was installed and whether the intonation was correct as installed. That .014" gap may have been included in the intonation adjustments of the guitar if the nut being replaced showed that gap. Or the gap needs to be closed for correct intonation.

[charles Tauber]

irrelevant..........

[dmaynard]

The way I interpret the drawing in the OP is that the .014" clearance is between the nut and the headstock. There would be no problem with intonation. The drawing is rotated 90 degrees from the way we normally view it.

[charles Tauber]

Originally Posted by dmaynard

The way I interpret the drawing in the OP is that the .014" clearance is between the nut and the headstock. There would be no problem with intonation. The drawing is rotated 90 degrees from the way we normally view it.

The drawing is clearly labeled as you state. My mistake.

[jonnycat]

Hi guys, sorry for the confusion. I was going to extend the fretboard down to show some frets, but given the scale of the drawing it would have extended down too far.

As to the original nut (this is from a 2014 PRS SE Custom), it was originally set back on what seemed to be a thin section of rosewood. Parts of this angled shim remain on the original nut, while some parts remained adhered to the headstock, creating an uneven surface (I did scrape them off).

To complicate matters, at the point roughly 1/5 from the top of the nut, the headstock assumes its final angle, which was noticeable when inspecting the original nut (it was partially filled in with the finish coat) It is as if they originally planned on using a shorter nut (or shorter fingerboard) for the guitar. I added a drawing on the bottom of this post to show this.

In any case, I ended up having just enough material on the new nut to angle the back of it to fit (which is good because I was unable to find a source of veneer that didn't involve either a hot glue coating or a 500 foot roll of the stuff.

[mirwa]

Too many unknowns happening.

I would fit the nut as is, tune and check intonation at the nut, from that information i would shape the nut or fretboard accordingly

Steve

[Robin, Wales]

Originally Posted by jonnycat

Hi guys, sorry for the confusion. I was going to extend the fretboard down to show some frets, but given the scale of the drawing it would have extended down too far.

As to the original nut (this is from a 2014 PRS SE Custom), it was originally set back on what seemed to be a thin section of rosewood. Parts of this angled shim remain on the original nut, while some parts remained adhered to the headstock, creating an uneven surface (I did scrape them off).

To complicate matters, at the point roughly 1/5 from the top of the nut, the headstock assumes its final angle, which was noticeable when inspecting the original nut (it was partially filled in with the finish coat) It is as if they originally planned on using a shorter nut (or shorter fingerboard) for the guitar. I added a drawing on the bottom of this post to show this.

In any case, I ended up having just enough material on the new nut to angle the back of it to fit (which is good because I was unable to find a source of veneer that didn't involve either a hot glue coating or a 500 foot roll of the stuff.

Great to hear you have a solution! I have seen this problem on many guitars. Usually, I'll be making the nut from a blank and so shape it to fit. But I also have an envelope full of marquetry veneer off-cuts which have proved very useful for glueing to nuts and saddles over the years. It is worth putting a call out locally to see if anyone has marquetry off-cuts to spare - they are a guitar techs secret weapon!

[jonnycat]

Thanks for the tip Robin. I used to have a bunch of 2" maple edge banding (several 8' strips) years ago, but they didn't make it through my last move. I did notice some smaller quantities of veneer strips on ebay; not something I use on a regular basis but when you need it, you need it!

[Robin, Wales]

Originally Posted by jonnycat

Thanks for the tip Robin. I used to have a bunch of 2" maple edge banding (several 8' strips) years ago, but they didn't make it through my last move. I did notice some smaller quantities of veneer strips on ebay; not something I use on a regular basis but when you need it, you need it!

Would you believe it - I needed a piece of that marquetry veneer last night! I decided to make a new nut for my favourite guitar, which is actually a second hand Art & Lutherie Legacy (I know, it is only a very cheap guitar but it has such a dry growly tone I love it!). I love everything about that guitar - except the nut's string spacing. The guitar has a 1 11/16 neck with rolled edges and was fitted with a Tusq XL-1728-00 nut. The string spacing is 35.2 and they are set with equal spacing between the strings rather than equal centres.

I lost the last section of my index finger on my left hand in a rock fall whilst climbing 15 years ago or so. So what's left of that finger is a little fat on the b string in a C chord shape. I needed just a little more room. So I shaped up a nut from a rectangle bone blank with about a 1mm more overall spacing and shifted to equal centres, which gave a greater increase in the spacing between the first 3 strings. And I now have a clean playing C chord - Yippee!

I went just a fraction too low on the 3rd string when cutting the slots (too much of a hurry!) so a piece of that marquetry veneer came in handy!!!!!