Nut Slotting

Devil#20

Keefy said:

I use the technique set out in Dan Erlewine’s ‘Guitar Player Repair Guide:

Measure the fret height by stacking up feeler gauges under a string or straight edge between the first and second frets. Add 5-10 thousands of an inch to the stack and place it under the strings next to the nut. File the slot at a slight angle down towards the headstock and when you feel the file bite on the metal feeler gauges, stop.

Check out the book for the full description.

He seems to know his stuff. Watched some YouTube videos and now ordered his book. 

BillDL

The easiest way to assess whether your nut slots are deep enough or too deep is to fret a string at the 3rd fret and then look at how much it clears the 1st fret by.  If it is touching the 1st fret the slot is too low.  If you have to press the string down onto the 1st fret the slot is too high.  You should be able to tap the string over the 1st fret, hardly see it moving at all, but hear a quiet "ting" as it touches the 1st fret.  You should just be able to see the gap between the bottom of the string and the crown of the 1st fret.  Usually you need marginally more clearance for the bass strings than you need for the treble ones.

Find a guitar that you know is set up correctly i.e. doesn't take much pressure to hold down an open E or barre F, and doesn't raise the pitch of certain strings when fretting the chord.  Do this technique on that guitar and you will get an idea of the small amount of clearance you are looking for over the 1st fret.  As mentioned earlier, it doesn't take much filing or cutting in the slot to get the right height or to go too far.  The same is true of filing down the underside of the nut, and removing it to do so isn't something I would necessarily recommend.

It's quite easy to chip out bits of the fretboard removing a nut, and if it has been glued in with more than two tiny dabs of glue you can end up pulling bits of wood from the nut rebate that remain stuck to the underside of the nut.  You then have an uneven base for the nut and deepening it to make it level and square again can easily go wrong, or at the very least negate having removed the nut to file off a sliver from the base.

Mellish

The chap who I rate is Bryan Kimsey. Have a look at his website.

Saying that, this forum isn't without its fair share of good luthiers/techs  

ICBM

BillDL said:

The easiest way to assess whether your nut slots are deep enough or too deep is to fret a string at the 3rd fret and then look at how much it clears the 1st fret by.  If it is touching the 1st fret the slot is too low.  If you have to press the string down onto the 1st fret the slot is too high.  You should be able to tap the string over the 1st fret, hardly see it moving at all, but hear a quiet "ting" as it touches the 1st fret.  You should just be able to see the gap between the bottom of the string and the crown of the 1st fret.  Usually you need marginally more clearance for the bass strings than you need for the treble ones.

This - the easiest and also the best way, because it takes the action height and relief out of the equation, which can otherwise affect what you’re seeing.

You don’t ‘need’ feeler gauges, but they can be helpful if you’re unsure what you’re looking for or how tiny the gap you want really is.

The gap should be around a quarter of the string diameter, or even less - as low as a tenth of it, ie between .001” on the plain E string up to about .010” on the low E at the outer ends of the range. (If .001” sounds too small or difficult to achieve without risking going too far, up to .010” can work OK for the thin strings too.)

From the description of the strings being hard to fret, I’m guessing it’s *miles* higher than this. If it is, cutting the nut correctly will make an enormous difference, almost hard to believe how much until you’ve played it before and after.

TheMadMick

^^   I bought a Takamine many years ago and it had a high nut although I didn't know that at the time - it was simply hard to fret at the top of the neck. Sent it back to get fixed and, as ICBM says, you wouldn't have recognised it as the same guitar. A pleasure to play (whatever you think of Tak"s)

Hard to get right but a real pleasure when you do.