Matching Nut files to string gauge when making a nut - how critical is the match?

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Bawdy5150
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Matching Nut files to string gauge when making a nut - how critical is the match?

Post by Bawdy5150 » Wed Sep 13, 2017 4:31 pm

Hi All,

Been lurking for a while, thought it time to join etc. I am in the process of making a nut for my first guitar and have a question re matching the nut file to the string gauge.

Its probably easier to explain with an actual example: The A string I am using is a 38 gauge string, but only have a 36 or 40 gauge nut file. I cant seem to purchase a 38 gauge nut file, so should I use the 40 or 36 gauge nut slot file? I am guessing it should be the 40, a little oversize as opposed to undersized using the 36?

I hope that makes sense?

I look forward to your replies.

Paul.

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kiwigeo
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Re: Matching Nut files to string gauge when making a nut - how critical is the match?

Post by kiwigeo » Wed Sep 13, 2017 4:57 pm

A 38 gauge nut file won't cut a slot that's exactly 38 gauge.....unless you work the file with absolutely no wiggle. Cut the slot with the 36 gauge file and you'll find there's a high chance the string will fit the slot...if it doesn't then wrap some wet and dry paper around the file and run it through the slot to widen it a tad.
Martin

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Steve.Toscano
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Re: Matching Nut files to string gauge when making a nut - how critical is the match?

Post by Steve.Toscano » Wed Sep 13, 2017 11:51 pm

My rule is to use the file wider (but closest) then the string. So in this case the 40.
I make my slots shallower then most seem to, about 1 3rd of the string sits in the slot.
I start my slots with a jewellers saw which tends to limit the wiggle martin mentioned.

old_picker
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Re: Matching Nut files to string gauge when making a nut - how critical is the match?

Post by old_picker » Thu Sep 14, 2017 8:50 am

I've cut a lot of nuts over the years and always leave plenty of wiggle room in case the next owner wants to go heavier with the strings. I'll cut with a file round .005" - .010" bigger than the target string and begin by cutting the slot with 400 wet n dry around the file. The breakk angle must be right and the bottom of the slot must be rounded. Also you want enough space between the string and fret #1 so you get no fret rattle when playing open strings and not high enough to pull your intonation out. It is a bit of a balancing act but with the right tools and some patience its an easy, relaxing job.

Others will have different methods but I find mine works well here and I don't get complaints about my nut work.

Bawdy5150
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Re: Matching Nut files to string gauge when making a nut - how critical is the match?

Post by Bawdy5150 » Thu Sep 14, 2017 4:20 pm

Guys, thanks for the replies, I had never thought of the 400 grit sandpaper wrapped around the gauge, clever. Thanks again, I will post a photo when completed.

Paul.

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kiwigeo
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Re: Matching Nut files to string gauge when making a nut - how critical is the match?

Post by kiwigeo » Thu Sep 14, 2017 4:30 pm

I tend to open out my slots on the rear side of the nut so this is another reason I tend to go for a file that is same size or smaller than the string gauge. In the process of opening out the slot rear wards it tends to widen the throat of the slot.
Something else I do is rub a bit of candle wax on my file...it stops chatter and makes for a smoother cutting operation.
Martin

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demonx
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Re: Matching Nut files to string gauge when making a nut - how critical is the match?

Post by demonx » Thu Sep 14, 2017 5:30 pm

I always use a file that is the one I have closest to yet larger than the string gauge. Larger so the string doesn't bind.

blackalex1952
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Re: Matching Nut files to string gauge when making a nut - how critical is the match?

Post by blackalex1952 » Mon Sep 18, 2017 1:37 pm

If I am out and about, ie not in the workshop without all my tools and have to make or repair a nut I have had success with the following improvised processes. I will also mention some basic principals, which you probably already know.
When cutting nut slots, I visually divide the headstock angle by two, and the angle from the nut slot to the tuning machine post also by two. I then define the slot with an appropriate width saw not cutting full depth then slowly refine as I work down closer to the depth I want. I have used coping saw, jewellers saw and different hacksaw blades, any thing that with a little imagination will do the trick. The saw bladewidth can be adjusted with a hammer and iron surface, and with an oilstone or emery paper glued to a block of some sort. The width needs to be less than the full width at his early stage. Then feeler guages can be used to arrive at a slot depth height if really necessary, but I usually tap to hear the clearance over the first fret while pressing the string at the second fret. One can also see the string clearance over the fret.The actual height depends on the guitar set up and on how hard or lightly the player plays, particularly with steel strings. I slowly bring each slot down close to the ball park of what is required. I also, during this process, use old steel strings, the wound ones, to adjust the final height and width. When using the old strings, I use a guage of string slightly wider than the string to be fitted
(ie a heavier set), as a file, in each case. The round string, when used as a file and keeping the angles previously mentioned, also rounds the bottom of the nut slot so that there is good even contact for the string. The fact that the string when used as a file is flexible, the nut slot on the tuning machine side of the slot can be curved with a little down pressure to leave the back of the nut at the correct half angle to the string post and headtock angle. This results in the rear of the fret slot having a gentle vertical curve as it goes to eventually leave the nut to the string winder post, ensuring good string contact as well and helps prevent the string catching. The wound string method is a slow cut, so the final nut slot depth on the bridge side can be very accurately set at the same time. I initially arrived at this method as a money saving exercise, being partly of Scottish descent! A bit of practice and experience, as in most things will improve your skills. The idea of making the slot wider if in case the player wants to go to a higher guage doesn't rock my boat. I can always quickly widen a nut slot for higher guage with the string as a file method. Higher guage strings with a close action are stiffer, so the bottom of the slot in some cases can be infinitesimally lowerered at the time if done this way. The string file method also widens the slot. For the first and second also for unwound third string, I have collected a range of very thin wound thirds. The gypsy jazz wound thirds and other wounds from different instruments other than guitar also some 12 string thin wounds are worth collecting. If you follow my thinking, there are other ways to do similar things. They can even be used in a jewellers saw. My travelling kit contains short sections of these strings...compact and portable and easily manufactured. I do like the wax on the file trick too. Ross
"Everything I say on the topic is based solely upon inexperience and assumption!"

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TallDad71
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Re: Matching Nut files to string gauge when making a nut - how critical is the match?

Post by TallDad71 » Fri Sep 22, 2017 4:20 pm

Have you thought of using a cheap set of engineering drills? They come in loads of sizes and are great to use as a rasp to smooth the bed of the nut slot.

I admin that the top E drill is a bit flimsy but the others leave a great groove.

http://www.ebay.com/itm/New-20Pcs-Mini- ... 855?_ul=FR

These are examples of.
Alan
Peregrine Guitars

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Clancy
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Re: Matching Nut files to string gauge when making a nut - how critical is the match?

Post by Clancy » Thu Oct 05, 2017 1:59 pm

Just as an add to this,

I recently had to make a bass guitar nut and only had my 6 string nut files.
To make the wider slots I put 2 files together (whichever pair ended up matching closest to the string thickness).
The pair were usually a thicker & a thinner file, so I'd swap the 2 files around regularly to get an even slot bottom.
Then just round off the bottom with my thickest file.
Craig
I'm not the sharpest tool in my shed

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