Nut filing - MacGyver approach?
 

Hi all,

I wonder if there's a sane option that doesn't break your bank account to have a decent outcome for nut filing.

Every listing in eBay that is cheap, is a poorly design tool that do more harm than good.

I'm trying to set up a new nut and I need to file the slots.
Doing the 6th and 5th is reasonably easy.

For the 6th slot, I used the 4th guitar string and tightly wrapped it with a sanding paper to achieve round and well-defined slot.

For the 5th slot I did the same but I used the 3rd string to achieve decent results.

However, for the 4th and smaller slots, I'm in a problem.
They all require the much expensive nut filing that one can find in StewMac.

Are there any cheaper ways to help achieve decent results?
Using improvisations, household items?

Or any other eBay alternative of decent quality that is reasonably priced?

Otherwise, I'm stuck with a guitar that is unplayable :(

This is a fair price for a good quality set of 'Made In Japan' nut files.

https://www.ebay.com.au/itm/Guitar-N...g/111480267049

I bought a set of " nut files "


they are basically feeler gauges, rounded on the bottom edge,
and then given teeth, like a saw blade;)

That's still too expensive for my budget, but good to know about this option. Thanks.

How did you get the teeth on the feeler gauges?
I have a set of 32.

those are gas burner cleaners.

they do a decent job,. (meh..) but none are small enough to properly handle treble strings.

I've been using needle files for the last 25 years. I did however just get some nut files, they do make nice U-shaped slots.

But anyway this is all you need, well and a bit of technique too. The ones they call knife and crossing will probably take care of everything.

https://www.amazon.com/SE-10-Piece-D...79087093&psc=1

Are they thin enough for the trebles? 1st/2nd/3rd strings?

Commercially made dedicated fret files first came to market in the 1990’s. For the centuries prior to that, instrument makers used needle files. I used needle files and an Xacto saw for about 25 years before switching to dedicated nut files.

Needle files will produce perfectly functional v-shaped slots, rather than the u-shaped slots of dedicated nut files or the straight, flat-bottomed slots of saws. I have found no functional difference between v, u and flat- bottomed slots. Saws are now available in a variety of kerfs to match common string diameters.

These days, I exclusively use saws for the top two treble strings, for roughing in all slots and for any string where the kerf produced appropriately matches string diameter, The saws cut much more quickly than files and are a little cheaper than dedicated nut files. However, unlike files, saws can’t really be rocked in use to produce wider kerfs. For string diameters where I don’t have a corresponding saw, I use nut files. However, needle files can just as successfully be used for all nut slots.

Thanks for the reply.
I have found one on eBay Australia with a 3mm width and with all the required shapes as mentioned above, the cross and the knife will be used most.
However it’s only 120 grit. Is that ok?

This is the eBay listing

About ten years ago I bought these nut files that someone was selling on ebay, quite cheap. They were actually feeler gauges that someone had turned into a nut file by cutting some saw teeth (kind of) on them.
As I said they were quite cheap and not the fastest tool on earth, but they worked fine and actually I still use them! So for sure something like this would be good for you.
Unfortunately it was long ago so I don't have any records related to it.
There's a picture here:

https://ibb.co/3mLZv2t

Thanks. I’m thinking of using a feeler gauge wrapped with sanding paper.
Just not quite sure it would work for the B and high E

I think you would need a very thin feeler gauge for the first two strings, not sure it would work. For the other strings maybe...
For the first two,you can use a thin saw as someone mentioned before.

Yes the Exacto razor saws can be used for the first two. And when you think about it, no one cuts slots in the saddle right? Well I've seen it done a few times but it's by no means the norm. So at the saddle the string just rides right over the top of the bone piece to the bridge holes. A nut needs a little guidance even if it's pure straight through pull since the break angle is much less then the bridge, but as Charles mentioned it doesn't matter if it's a V or a U shape. The string due to the tension and the downward pull is going to find it's happy spot at the bottom of the valley and all you really need is for it to be deep enough to hold it in place. So if that valley being U or V shaped is a bit too wide for the string [dare I say *gasp] who cares? If anything it's worse having slots that are too narrow and bind up the strings.

The three important things about nut slots is that 1) they hold the string in place and don't bind 2) they are spaced equally so no strings are too close or too far apart relative to the others and 3) the slot depth is equal too or only very slightly taller then the fret in front of it.

You can accomplish that in many ways

Two words ……. Harbor Freight

Can you please explain the "don't bind" thing? I don't fully understand what it means.
The current way I filed my 6th and 5th nut slots are filing to a measured height, say 0.51mm above 1st fret. I then marked the slot with a lead pencil and started to file in an angle equivalent to the head angle, to create a take-off point. I made sure that the front of the nut (closest to the fretboard) doesn't get filed and the lead pencil mark is untouched. The back of the nut had an angle to create that take-off point.

But still not clear what binding is in that regards.



I can't find a way to set the shipping to Australia

binding happens when the slot is too thin for the string and as you tune up the string gets stuck, or binds, in the slot then releases and you usually hear a ping ping ping sound.

And yes you definitely want the string to exit on the face of the nut.

Thanks for the explanation.
When you mean the string to exit on the face of the nut, you refer to the fact that the depth of the nut should be 1/2 to 3/4 of the nut diameter?

No that is not what I meant thought that is also true. I tend to bury the treble strings a bit more then the bass because they (treble) tend to get bent a lot.

What I mean by the face of the nut, and you actually mentioned this earlier and I was just agreeing, is the surface of the nut that touches the end of the fretboard. That is the very start of the string length.

I use a combination of a small "back saw" that I reserve for "roughing in" the slots, skewing the blade to widen the slots where needed.

I also utilize a piece of stainless hobby flat stock that's .015" and rounded on the edge.

I first cut slots and then wrap and hold 220 sandpaper over the rounded edge to finish the rough cut slots and create the smooth and rounded bottom. Wider slots simply get 2 or more layers bent over the edge of my "slot tool". The smallest slots can simply be finished by doubling over a piece of sandpaper to smooth the slot and round its bottom.

I've done it that way for many years. I'd purchase good nut files if I cut slots all the time, but it's not a daily endeavor for me.

https://www.hangoutstorage.com/banjo...2102442013.jpg

The StewMac set is only $89, not hundreds of dollars.....
https://www.stewmac.com/Luthier_Tool...ic_Guitar.html

It would be about a couple of hundred for both sets. I was looking at these as being more useful and they work for basses too:

https://www.stewmac.com/Luthier_Tool...Nut_Files.html

Anyway, even $90 is too much for me at the rate I make nuts (from the dog's old soup bones, so they're free.) :)

Are the blades in the jewelers saw stiff enough to stay straight? If they bow then I would be worried about putting the point of string contact apex of the nut slot in the middle of the thickness of the nut rather then right on the face.

There is enough tension on the blade that it is straight for practical purposes, especially with lighter downward pressure when finishing the cut. In any case, since the slot is angled downward toward the tuning pegs, even the apex of a curved slot would be below the level of the slot as it leaves the face of the nut.

I made these by belt sanding down different hacksaw blades, then rubber coated the ends. I have several sizes.

Ed

https://previews.dropbox.com/p/thumb...ue&size_mode=5

I made my own set of feeler gauge files with a Dremel and a diamond disc cut-off wheel. Not hard to do, and as you can see from the sloppy job I did, it's pretty forgiving - about 10 - 12 teeth are enough. Micarta and bone nuts are relatively soft.

The acetylene tips aren't super sharp but they work ok for the 4 thicker strings, then the feeler gauge files works great on the thinner unwound ones. You might use a feeler gauge to do the thick slots to depth first and then finish with the tips since they cut pretty slowly (and leave a nice polished finish). eBay Australia might have a set pretty cheap or Amazon maybe? Be careful on the thin feeler files, they can go too deep a lot faster than the thicker ones, then you have to start over with a new blank.

If you haven't yet, I'd suggest taking a look at Frets.com which is my favorite do it your self guitar tech site: http://www.frets.com/FretsPages/Luth...ut/setnut.html

Good luck with it!

https://i.imgur.com/NvhQOeZ.jpg

Caution! I found that you can take away way to much real fast. Go cautiously slow.

I once cut string slots in a blank fossil mammoth ivory ukulele nut with a Ka-Bar.

And I wasn't even one of a small group of survivors facing a zombie apocalypse at the time!

Thanks everyone for the help.
I've ordered a set of 10 pcs diamond-coated files, 3mm diameter, as stated in my posts before.

I managed to get the 6th, 5th and 4th slots as I calculated.
They have about 0.5mm (6th) to 0.58m (4th) clearance from the bottom of the string to the top of the fret.
No buzzing and quite comfortable to press.

I also did the test where I press the string near the 3rd fret, between the 3rd and 4th fret and check the clearance on between the string and the 1st fret.
there's a tiny crack of light.
I need to check with my feeler gauge how much of clearance, but the point is, no buzz and comfortable fretting.

I tried to round the bottom of the slots using a carefully folded sanding paper and pencil marks.
I made sure to put an angle at about the same as the head, but also direct the back of the nut slot to the tuning pole.
I didn't do the most accurate job, but considering the tools, I believe it's ok.

I'm now facing the 3rd, 2nd and 1st to work with.

As mentioned, I'll have these slots a bit deeper since the strings tend to be bent a bit more.

I'll report back once I'm done.

So a bit of an update.
I got those diamond filing for the nut and I don’t see how I can use them for the G slot.
What’s worse is I’m about to give up :/
I seem to not able to restring the G string. It keeps breaking.
I know how to restring but the G string just gets too much tension when at E3 so when I try to get to G3 it snaps.

Not sure what to do anymore. Thanks for all your help.