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I can't see the line I am scribing on the nuts when I go to for the starter cut? I remember somethinfrom metal working day applying something 'bluing' was it & then maing the mark?
Any tips please. I'm making too many bad cuts. Also how do you alter it if you start wrong?

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Mike McNerney

A .5mm pencil line is perfect for width line. I have a saw the right gauge to just remove the mark.

I use a 0.3mm pencil to scribe my lines. And an Optivisor to see them - works for me. For nut slots I clamp the nut in a Panavise and start all the slots with a razor saw to a depth of about 0.040". I guide the saw with my thumbnail so I am able to make it track exactly on the line. Next I use the files to get the slots to the right width, again only going down about 0.040" or so. I find it to be real easy to get the slots started on the Panavise then move it back to the guitar where the shallow slots help the strings sit where I want them while I finish up each slot.

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Steve Smith
"Music is what feelings sound like"

"Bluing" is a dye that machinist put on a piece of metal, then scribe their measurements - the scribed line stands out against the purple-blue back ground. Don't put anything like that on bone, it will soak in and you'll have a nice blue nut.

Like the others, I use a mechanical drawing pencil (0.5 mm) and then make a cut with a 0.010 saw. I also start with the blank a bit too tall so if I do "start wrong" I can angle the slot in the direction it needs to go as I open it up with the nut files. ps - the StewMac nut spacing rule makes it a lot easier.

I use a scribe to make the mark. This provides a notch for the saw to register to when cutting the initial slot. I can feel the saw when it finds the notch. No eyes needed ;-).

What you folks don't make your nuts on the guitar using the strings to 1). hold the nut blank in place and 2) show slotting as you go?

I make my nuts on the guitar using the outer e strings to hold the blank in place and the stew-mac nut slotting rule for spacing between the outer e's. Outer e spacing is a function of if any lousy, cheap f*ctory over beveling of the fret ends exists, player preferences, prior spacing if that was good for the player and as Dan E. writes in his book, what looks right.

I make a mark with the finest mechanical pencil that I have and then use my .016 gauged Stew-mac nut file to start the slot. Fore some of the wider slots such as say a .056 I use a .020 file to start the slot. All you need is 2 - 3 swipes of the file to get things started. The marking/starting files remove the pencil mark.

Once I do the outer e's I use the rule and find the inner remaining strings. For each one I do and again this in on the actual guitar I check myself with the rule again.

Based on how I'm doing with my nuts..... I slant the files I'm using to walk things left or right accordingly.

Lately I've been trusting my eyesight more and purposely avoiding using the SM rule beyond perhaps one check per slot. I found that it was a bit of a crutch for me and wanted to speed up the process too. The rule is a great tool, highly recommended but in my case I was picking it up 20 times per nut and that's way too much.

For setting slot depth as well as spacing being a function of fret ends AND even prior spacing if there is any wear on the frets making nuts on the actual instrument is greatly preferred here.

The guys who have taken our class will understand what I mean by using the outer e's to hold the blank in place as we recklessly wrench with great big sharp metal tools on the actual guitar.....

I'm telling Dave.......

Hesh

It took me a few nuts to figure out that it helps to reduce the height of the blank before you start the slots to reduce the amount of slotting you have to do. I use the 1/2 pencil to find the lower limit of the slot, and a full pencil to mark the upper limit that I trim the blank to. What do you use to find an upper limit that allows you to remove the right amount of material?

Ed

Guess I'll have to be ready to duck and run next time I come up there.

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Steve Smith
"Music is what feelings sound like"

Hey Ed: Right you are and you can also avoid file binding by also taking excess material not only off the nut top but by milling in a back bevel of the nut shape appropriate for the instrument if it's going to have a back bevel.

As for measuring and marking I do it by eye and experience. I know from experience what a .056" string looks like and I may know and should know what gauge of strings the ax is going to have on it. So with this said after the half pencil thing that I do too I just draw in the upper line making it slightly more than the bass e width and progressively bring the upper line closer to the lower, half pencil line knowing that my lower limit will be around .013".

FWIW the slot depth half the width of the string thing is not something that we subscribe to and we believe that our friend Dan E. started it. Why don't we subscribe to it? Because some players who hit harder can rip a high e right out of a .005 deep slot especially when with wear the slot gets wider. The same holds true for a .013" string in a .006" deep slot. Bending in the first couple of frets area can rip a string out of a shallow slot too.

Instead our slot depth is initially determined by slotting the nut blank on the guitar as mentioned above and then setting initial depth also on the guitar. Once we have near final depth we take a big arse bastard (file not like the bastards in Game of Thrones...) and file the nut top material down on the guitar with sacrificial strings on. Yep we file until the file is hitting the sacrificial strings.

Next the nut is finalized, sanded, polished and the ends are final fitted to be absolutely flush AND continue any lines found in the neck, headstock transition and then the nut is installed.

When I string the thing up after this the nut slots are cut to final depth with the new set of strings.

What results is our slots for say a .012" string may be around .012" deep. Every day I cut f*ctory instruments and Luthier instruments as well cutting the nut slots usually way lower than they came from either source. In many cases you might find a .030" deep slot for say a .010 string. It doesn't hurt a thing for the slot to be overly deep but to my eye it does look like crap.

You know for the folks who can't get the half string diameter thing out of their heads you can still do this with the nut off the guitar during sanding and polishing. We just don't recommend this because it limits functionality.

After all guitars are tools for musicians.

Oh yeah one more thing that I thought of that I wanted to add. Back to files binding. On the down stroke with a gauged nut file scraping the slot sides goes a VERY long way toward preventing file binding. It also goes a very long way in producing a nut slot that does not bind the string and you won't hear that "tink" sound as you watch your tuner display jump....

To be clear with file in hand and file attacking the slot I scrape the slot sides on the down stroke at least a few times on both sides to prevent binding of either string or file.

Naw, he's used to me not listening to him either.....

Until a nut blank is sanded and polished, the surface does a good job of showing a fine pencil line, so we do our layout on bone with a 0.5mm P205 Pentel mechanical pencil (with HB polymer leads) after smoothing the radiused upper surface with a 6" mill bastard, which provides a very smooth surface if a draw-filing technique is used. Most string nuts we make are proportionally spaced (including mandolins, etc.), so we mark the outer string center locations based on user preference, then use the Stewmac string spacing rule to complete the layout.

The slots for both ruler and for our fixed spacing guides, as well as Incra-type rules are set up for 0.5mm mechanical pencil use, which leads to a neat trick for accurate cutting. Once marked, the pencil line will be about 0.020" wide, and the Zona fine tooth razor saws are close to a 0.010" kerf. If the saw is placed on the mark with just the edge of the pencil line visible, then drawn back to start, the cut usually ends up nicely centered between the edges of the lines.

For layout on ebony nuts, we have a pencil with mint blue 0.5mm lead from JetPens.com, an importer of all things pencil-related from japan - not quite as good a white lead, but much better than regular HB leads. Jet Pens also carries our preferred shop pencils in 12 packs (Tombow Mono 100 4B) - not inexpensive, but very useful.

Let me ask about the SM string spacing rule:
I assume it shows porportional string spacing so the spaces between sides of the strings are the same.
Does this thing work with light and heavy gauge strings, or say heavy bottom and light top string sets?
Or is it set up to work with a specific set?
Been thinking about getting one.
Thanks,
Dan

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wah
Wah-wah-wah-wah
Wah

String set gauge doesn't matter it works the same way, very well with any set. Mandolins, banjos, guitars and where necessary for say notched saddles you can use it on the bridge end too for the spacings that it offers. It's a great tool for folks who understand commercial expectations and/or appreciate great results.

thanks to all. I'll try the penicl & keep the nut tall until I know I have it right. I don't think I have seen zona .010?

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Mike McNerney

+1 for stew- mac string spacing gauge ,I use a lot of different widths for nuts /saddles real timesaver

The Zona 35-200 has a 0.008" kerf, and is very controllable, but only has about 3/8" depth of cut...but it is still my favorite for nut slotting as it cuts on the pull stroke and alignment seems easier to me than a taller saw. The better choice for more general purpose work such as trimming braces and cutting the notches on the X brace or pocketing linings is the 35-500 saw, which has a depth of cut of about 1-3/16", a 0.010" kerf, and at 32 tpi, is smooth starting and reasonably fast cutting. The 35-550 is a little finer at 42 tpi, but otherwise identical. None of these saws cost more than $13 or so through Amazon Prime.

Hesh has it spot on!
Mike

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Mike Collins

I do it like Hesh too.

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It's not what you don't know that hurts you, it's what you do know that's wrong.

Rather than go through the tedium of marking the slot positions on the nut using
conventional rulers etc. I have devised this method, which takes advantage of the
accuracy of my CAD program. I simply layout a grid of lines with the centers and the
edge strings placed to match the fingerboard width. Since I can print to scale the grid
can be used as a template to mark locations on the nut. A 3/16” strip of the grid is cut
from the sheet. I apply a small amount of “Elmer’s” to the nut blank. The ends of grid
strip are lined up with the edges of the nut and the strip is glued in place. Note that the
high “E” and low”E” are spaced from the edge at different dimensions. Free CAD
software can be found here http://www.freebyte.com/cad/cad.htm#2D3DCADSystems

Looks like this

http://www.kennethmichaelguitars.com/si ... 50x187.jpg

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Ken Cierp

http://www.kennethmichaelguitars.com/