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Making Bone Nut for Guild F50 Guitar

I need to give the lacquer I sprayed on the top of the guitar some time to dry before I can rub it out.  I'll probably wait at least two weeks, and the rest of the guitar will be done in the meantime.

Now I need to make a new bone nut and saddle.  The old saddle had been shaved down to compensate for the bad neck set.  Now we need a taller saddle.  I'm going to make a new bone nut to replace the old plastic factory nut.

The first order of business is to get the old nut out.  I use a wood block on the front and back of the nut as a caul and tap it a few times with a hammer.  Usually that pops the nut out.

In this case, however, the nut slot is fairly deep and the nut is in tight.  I can feel it wiggle a bit, but I can't pull it up from the top.  I decide to tap it out from the side.  Be careful if you try this - it's easy to have your drift slip and hack the guitar.

I taped the surrounding areas up and carefully used my Destructo screwdriver as a drift.  A few light but firm taps moved the nut sideways.  It doesn't look like it was glued in at all.

Here's the old plastic nut and saddle.  If you ever want to compare the tone and hardness of plastic to bone, do this experiment:  drop a plastic saddle onto a concrete floor.  Then drop a bone saddle.  The plastic just goes 'pink' and sounds thin.  The bone will go 'ponk' and will have better tone. 

Crazy?  Try it for yourself.  Once you hear the difference, you'll never use plastic again if you can help it.  Bone is also much harder and will last much longer than plastic as well.

Ok.  Now take your bone blank and sand or file it till it's a tight fit in the nut slot.

I put tape on the fingerboard and headstock to protect them from errant files.  Then I mark the tape to indicate the top edge of the fret end bevels, and then measure in about .055 of an inch.  These will be my outer two (e.g. the low and high E) string slots.

In this case, my measurement was probably closer to .070 - not a disaster but perhaps a bit too far in.  I'll have to see how it plays after it's strung up.

I use a razor saw to make an initial cut for the outside two strings.  Then I use the amazing, wonderful Stew-Mac nut slotting gauge to mark the rest of the slots.

If you make more than one nut in your life, you need this gauge.  It's proven to be such a time saver and has brought so much accuracy to my nut-making that it has become indispensable.

The gauge has a few dozen slots marked in it.  You align two of the marks exactly to your outside string slots.  Then use the four marks in the same row for your inside strings.  See how there are two rows of slots - on is closer to the edge than the other?  You need to make sure you use the same row for your slots.

They will then be perfectly laid out!  I put arrows on the picture above to illustrate.  A little hard to explain, but once you see it, you realize how wonderful the gauge is.

Now I line up my nut files and nut slot files.

Looks like surgery.  Am I a surgeon?

I think of myself more as a sturgeon?  I like caviar!

I've filed my slots by eye in the past, but this time I'm going to try a new approach.  I'm using a feeler gauge as a depth stop.

What I did was find the approximate height of a fret (about .038 of an inch).  Then I added a few thousands to that and stacked feeler gauge 'fingers' to get the height I wanted.  In this case, I went with .043 for the treble side, so I stacked an .020 and an .023 gauge.

Then I just filed down in the slot until the file just hit the gauge.  I added about .002 for each subsequent string across the fingerboard.   The strings vibrate in a bigger arc as you go from the G string across to the low E, so the height at the first fret (determined by the slot depth) needs to be a bit higher for each string.

Once I got the slots filed down close, I strung the guitar up and adjusted the truss rod.

Now I can do the final depth slotting.  I found that my estimates using the feeler gauges were very conservative and a bit high.  But it put me in the ballpark and I just gradually filed and adjusted the depth by eye for the final fit.

Each string now rides just a couple of thousandths of a inch above the first fret.   A lot of players don't realize how critical the nut slots are for good action low on the neck.  Most factory guitars I see have awful nut action.  It's understandable since most factories just crank out guitars, and fortunately it's easy to do a complete setup to get the guitar playing nicely.

A couple of final steps: I file down the top of the nut to follow the fingerboard radius (12 inches in this case) and to get the strings to lie perfectly in the slots.

Unwound strings should lie with their top just even or just slightly below the top of the nut.  Wound strings should sit with half of their height above the nut.  Making sure the strings are correctly set up in the nut helps them slide smoothly through the nut when tuning or when bending strings.  If the slots aren't right, the strings will hang up and not return to pitch correctly.

I also make sure the slot bottoms are rounded and are smooth.  I run 600 grit paper through the slots to make sure they're smooth.  I also generally dress the tuner side of the slots outward a little (think of almost a 'V' shape) so the strings won't hang up on that side of the slot.

Then we sand and polish the nut.  On this nut, I used 800 up to 3400 grit paper to polish, and then finished with fine and extra fine hand polish.

And here's the finished nut.  Nice and smooth and shiny.  Next up is the saddle.





 
 
 
 

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