Crawls Backward (When Alarmed)

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One Degree From a Squirrel...looking for a nut

So we have a complete body and ze neck is bolted (screwed) on. Now ve make ze string nut!

I've chosen 'vintage' bone nut which I got from Stewart-MacDonald (aka Stew-Mac). The vintage part means it's unbleached, not so bright white in color. They have a Fender size which is real close to whatcha need for an S- or T- geetar. You get your choice of flat bottom or curved. Now, Fender, since the dawn of time (which you know now from a previous post is 1949) has used a curved bottom in their nut slots. I have no idea why they did this - I believe most other manufacturers at the time were using flat bottoms. At any rate, when I ordered the neck from USACG, they recommended not even messing with the curved, "unless you really have to have one." I went with flat and it's a heck of a lot easier to work with.

You can see it's just a bit longer than the slot. It's also a tad wider. Whatcha do first is sand it flat on either side until it fits tightly into the slot. I sanded it with 400 grit wet paper.

After that, lay out the string slots. I used Stew-Mac's string spacing gauge. It's the best $20 I ever spent. Basically, you mark the slots for the outside strings - the low and high Es. I put them about 1/8 inch in from the edge of the fretboard. Once those are marked, you line the gauge up and mark the inside 4 strings accordingly. There *is* a mathematical way (old-school) of doing this, but math makes my head hurt, and I have a gauge!

Once the slots are marked, I used an X-Acto fine razor saw to make a tiny starter slot. Then start to file each slot in turn. I have nut slot files that are gauged - each slot should be a few thousandths wider than the string that will be in the slot. So on a .010 high E, for example, I used an .013 file. For the B - .013, I used an .016, etc. I bought a set of 7 files and they pretty much cover any gauge of strings you'd put on a geetar. As Dan Erlewine says in his great repair book, you can also 'fudge' some slots that need to be a bit wider than your file by "rolling" the file in the slot.

Note that the files cut only on the edge - and the cutting edge is curved in a "U" shape, which helps the strings not hang up - especially important for string bending (yup, me play de blues) and using the trem. If the strings hang up in the slot, they won't return to pitch - they'll wind up being sharp.

Once you have some slots cut a bit, string it up. Now we REALLY are gettin close to playin some music! (Considering the nut is made of cow bone, maybe it should be MOOsic...).

With the guitar strung to pitch, you can go back and cut the slots a bit deeper. There are all kinds of info out there about this...you can put a feeler gauge under the file that's a little higher than the fret height, for example, or you can eyeball it. I would up doing a bit of both. I did cut some slots too deep and wound up 'repairing' them. If the slots are too deep, the open strings will buzz at the first fret. If they are too shallow, they'll be hard to fret/press down on the lower frets. None of this is rocket surgery - nuts are cheap (about $3 each) so if you goof, it's a learning experience. Once you've done a couple, you'll get faster at it.

When the slot depths are looking close, take the nut out and put it in a vise so you can file the top down. The strings shouldn't ride too deeply in the slots - about halfway for the bass strings and almost the whole way for treble. Again, too deep and they'll hang up, too shallow and they may pop out when you're playing. You can see where I marked a couple lines to give an idea of how deep to file. In between the two lines is what I was shooting for.

It may take a number of passes to get it right - I think I had this one in and out of the guitar 5 or 6 times. Better to take file a small amount at a time to make sure you don't go too low.

You'll also need to trim the excess off the ends once the slots and overall depth is where you like it. Just mark the ends at the end of the fretboard, put the nut in a vise and saw em off with your razor saw. I filed mine down a tad too - I don't like the ends of the nut sticking out where I can catch it with my left hand when playing.

This is one of the great things about building your own instrument - you can make small customizations they way YOU want them. Of course, you can always make something like a nut for a factory guitar too if you want.

After you have it where you want it, sand it lightly with 600 then 800 grit paper, and polish it with rubbing compound. Here's mine before I put it in for good.

Put a couple drops of glue - wood glue or cyanoacrylate (CA...super glue) to hold it in. You just need a couple drops - a ton of glue may seep out and ruin your nice new finish. The string tension will mostly hold the nut in anyway, and if you have a good fit, the glue is almost not necessary.

 
 
 
 

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