Adjusting nut slot depth

living room rocker

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I've got 3 strings riding too high in the nut causing sharp notes on the first 3 or 4 frets. Don't really want to invest in a professional set of files for this one time need, although the local Harbor Freight sells a couple different sets of cheap needle files. Have no idea about the size/gauge of these files. I understand the string should rest on the nut opposite the headstock side, which requires a slight downhill cut. Any tips on how deep one should cut? A little at a time until the notes ring true? As donepearce has mentioned before, luthiers often leave slots a bit high because they're one stroke away from cutting too deep. What if filing the slots gives me perfect notes but cause an open string buzz.....the action of my guitar is quite low. Raise the bridge and/or adjust relief?
 

Go Nigel Go

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My best advice is to cut less then you think you need to, and try it frequently to see if it is better or not. If you just have a little ways to go you can use some fine sand paper (like 600 grit) folded in half. It may be slow going, but is less likely to inadvertently cause you to go to far.

Most needle file sets (like those from harbor freight and the like) have a variety of shapes and sizes, but they don't have a selection of thicknesses like you will need for doing a guitar nut. I have several sets for doing other jobs, but none of the sets I have from harbor freight were of any use for nut work.

Another cheap alternative (sort of) is the tip cleaning files for welding torches. The upside is they are super cheap to buy, the downside is they are less than ideal and problematic to use well. Here is an honest review of the practice from a luthier who gave them an honest try.
In short, maybe better than nothing...
 

Bad Penguin

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Go to Home Depot, or Lowes and buy a set of welding tip cleaning files.
WWO_TCS.jpg
Should be around the 5 dollar mark. A few passes and boom, done.
 

Go Nigel Go

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Yup, those are the welding tip cleaners, and they can be made to work in a pinch. I would highly recommend reading the article I linked above however if you haven't used them before which gives some good information on the potential pitfalls and how to avoid them. Forewarned is forearmed and the author tells how to use those to best advantage.
 

living room rocker

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I'll give those tip cleaners a try guys. I don't think it's going to take much to do the job and beats the cost of a pro set of files. Thank you.
 

MR D

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You can get a decent set of files for $60 @ Philadelphia Luthier Tools .com...it is worth the investment if you want to do your own set-ups/NUT Slots/Saddles.

Gibson Short-Scale Solid Body (or ES) guitars w/12" Radius w/.004" Neck Relief @ 8TH FRET (as close to DEAD STRAIGHT as possible without twisting the frets or kinking the binding (if so equipped)):

String Heights at 1st fret:
LOW 'E'= .023"
'A'= .025"
'D'= .027"
'G'= .018"
'B'=.014"
High 'e'=.011"

These 1st FRET string heights w/above ref'd Neck Relief will produce a perfectly DEAD ON RINGING Open 'A', 'E' and 'D' chords in the second octave. Check it with a tuner after you do it.....it took me a really long time to get this right......and I bet you any amount of $$$$/Euro's whatev...that any time you pick up a GIBSON USA Solid (or ES) Body electric guitar that is not one of mine...the 2nd octave Open chords are almost never RINGING DEAD-ON.......if you do what I just typed above.....your GIBSON USA (or CUSTOM) will never fail to have perfectly DEAD ON RINGING 2nd octave Open 'A' 'D' & 'E' chords.......there is a tolerance of +/- .0015" on each string.........what I just typed is a guarantee (YEAH IT IS !) as long as the guitar has a properly set up to GIBSON USA Specs T-O-M (OR ABR-1) bridge and is in non-warped condition w/good frets.

I FINALLY got it right about 5 years ago.Those 1st fret string heights are what did it....w/all else being set to GIBSON USA spec..
 
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living room rocker

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One more thing. If the base of the slot is not perfectly smooth when you are done, the string will sink some over the next few weeks. So don't try to go all the way in one session. Creep up on it.
Will do on the slow creep; thank you for that tip. I know the strings will be recessed into the slots further than half in, half out; most of them are already. You referenced not long ago about sanding/filing the top of the nut to achieve this goal. Do you recommend filing or sanding with what grit? The nut is Tusq.
 

donepearce

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Will do on the slow creep; thank you for that tip. I know the strings will be recessed into the slots further than half in, half out; most of them are already. You referenced not long ago about sanding/filing the top of the nut to achieve this goal. Do you recommend filing or sanding with what grit? The nut is Tusq.
If it is not uncomfortable just leave it. The half string thing is really just a bit of luthier vanity. Otherwise I would use a file, not sandpaper. Sandpaper is a bit uncontrolled and tends to wipe all the detail off edges.
 

Colnago

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I'll give those tip cleaners a try guys. I don't think it's going to take much to do the job and beats the cost of a pro set of files. Thank you.
It’s cheaper until they mess up your nut and force you to take it to a pro or buy a set of nut files.
 

Norton

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it's not worth trying if you don't use actual nut files.

Yes... it is possible to slot nuts with welding tip files and strings super glued to something.. but if you want to get it right the first time I'd suggest at least a set of the Hosco gauged nut files. the String height dial is also incredible for getting those nut slots precise.

I've tried just about every method out there. and the String Height Dial and standard issue nut files make the work quick, precise and very repeatable.
 

papagayo

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Look at a zero fret nut, the height is the same than other frets.


Temp 48102.JPG
 
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I'll give those tip cleaners a try guys. I don't think it's going to take much to do the job and beats the cost of a pro set of files. Thank you.

The tip files are fine for cleaning up slots or changing the angle a little. You can use a caliper to size them but it's easier to just put them in the nut slots and find the one that's the same size as the existing slot.

The small sizes tend to bend very easily. There's a video around where the "luthier" glues them to small blocks of wood to keep them straight as you work. If you're thinking that that won't leave you with enough file exposed to do your slot, then your nut slots are very deep. Ideally, the string sits in a slot about half the height of the string. If the slot is deeper than that, some material can come off the top. Luthiers usually do that when making a nut but lots of factory guitars and nuts have very deep slots.
 


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