Recutting nut groove?

[polkat]

Have a violin here with a very nice nut on it, well shaped an seemless fit. But, the D string groove is not quite centered and is closer to the G then the A by a noticable difference. I can feel this while playing the instrument. Since the nut is so nice, and my time is often short, I'd rather fill the old groove and recut it, then make a new one. But, what to fill the old groove with? Perhaps a tiny spec of ebony? Epoxy? Anyone here done this? Thanks!

[iburkard]

I would recommend a new nut (depending on depth of grooves), but perhaps someone will agree with your filler idea.

[David Burgess]

Doing a new nut nicely is a lot of work!

Use a plane to make some ebony shavings. Roughen the existing groove with a file, and glue layers of the shavings in place, using the string to clamp them in place. Multiple layers can be glued at the same time. When dry, remove the strings, trim the new material flush, and relocate the groove.

This usually works pretty well, and seems to hold up much better than other types of fill.

Waxed paper can be used between the string and the shavings so they don't slide much when bringing the string up to tension, or get glue on the string; and a piece of tape can be used to keep anything from sticking to the fingerboard. I've used Titebond. A waterproof glue might be better.

[colledge]

I've used this black opaque super glue to fill little dings in ebony before. It files and sands a way nicely.

Though I normally just replace the nut, I know it could do the job.

http://www.stewmac.com/shop/Glues,_adhesiv...Super_Glue.html

[lyndon]

what i do is remove the nut glue a piece of business card paper or veneer underneath to raise it slightly then reposition the grooves lower and file the top lower by the thickness of the paper, sincerely lyndon

[Guest erich_zann]

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[David Burgess]

The reason for going to the trouble to glue in shavings is that I haven't found any fillers (including superglue) that wears nearly as well as wood. The wood seems to hold up unusually well to the abrasiveness of string windings sliding over it.

[Michael Richwine]

I run across this quite a bit in older instruments. I usually set the string height at the nut at 0.3mm (.012). Many times the strings are quite a bit higher. so there's often room just to file the nut down and re-cut the grooves. They only need to be about 0.1mm deep.

If that won't work, I'll just shim the nut with ebony and redo the top of the nut. Do even a halfway decent job, and it's pretty much invisible.

[welshman]

I find that if I am moving more than one groove then the idea of adding a layer of ebony veneer to the bottom of the nut and then shaping and recutting the grooves saves having to make an entire new nut, if I just need to move one groove and the new groove is not going to be back on top of the old one then super glue and ebony filings will fill the surface to hide the old groove, like David I am leery of having the glue/dust combo in the new groove position - I would opt for option one. On inexpensive instrument (on a budget) strips of business card stock glued to the bottom also works, color the edges black with a marker.

Reese

[polkat]

Thanks guys, some good ideas here. Since the new groove will be pretty close to the old one, I will try David's idea of filling the old groove with a bit of ebony first. I'm a bit concerned about the string wear issue as well. How well does super glue really work with ebony?

[chrisandcello]

I'd go in order of preference

1. new nut

2. superglue mixed with combo of ebony and graphite dust (graphite reducing string friction)

If the nuts coming of for a shim and re-profile...may as well have a new one

How well does super glue really work with ebony?

It works fine on fingerboard end cracks and also with dust to fill...

[Michael Richwine]

I'd go in order of preference

1. new nut

2. superglue mixed with combo of ebony and graphite dust (graphite reducing string friction)

If the nuts coming of for a shim and re-profile...may as well have a new one

It works fine on fingerboard end cracks and also with dust to fill...

I don't know about you, but I can shim a nut and reshape it in about 1/3 the time it takes me to do a good job on a new one. I keep 1/2mm ebony shim stock on hand, and the results are invisible to anyone who doesn't do a lot of repair work, and often just plain undetectable.

I think I'll leave it to others to comment on mixing graphite powder with ebony and superglue. Doesn't appeal to me, although we routinely use superglue and ebony dust to repair minor defects in the fingerboard surface.

[iburkard]

The idea of adding an ebony shim must work if so many of you guys do it, but I don't prefer it. Perhaps I'm still too young/dumb to worry about saving energy at this point in life.

Making a nut is not hard, plus you might get ill fitting results by shimming, since some nuts are \___/ shaped - conform with the fingerboard/neck cross section. The width would be too skinny/shy if elevated.

[polkat]

What I ended up doing is I used an Australian super glue called Q-Bond. which will glue anything. It comes with a filling powder that I think is a mixture of graphite and iron...not sure. Anyway, I filled the old groove with that, let it dry and sanded any excess back to shape, then buffed it out with 0000 steel wool. Cut the new groove and done. The color match was only slightly off, so I used a drop of some old board dye I had laying around...and you can't see it! Worked great and only took maybe 20 minutes total. Then again, I probably wouldn't have done this if the groove was very deep or the nut damaged.

You probably can't tell much from the pic, but here it is (the pic is shot at a slight angle)......

Thanks for all the suggestions.

[Guest erich_zann]

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[mmmm]

I've always been very sensitive to the spacing of the strings on the nut...too far apart or uneven will drive me "nuts".

A related question to the makers here: have any of you noticed whether or not the depth of the grooves on the nut can significantly affect the tone? For instance, will a deeper groove on the G string create a richer sound? (I apologize in advance if this is a ridiculous question...)

[Michael Richwine]

I've always been very sensitive to the spacing of the strings on the nut...too far apart or uneven will drive me "nuts".

A related question to the makers here: have any of you noticed whether or not the depth of the grooves on the nut can significantly affect the tone? For instance, will a deeper groove on the G string create a richer sound? (I apologize in advance if this is a ridiculous question...)

IME, you generally get the best sound with the grove depth less than half the string's thickness on nut and bridge. It's more important with the bridge, but the nut seems to work better with shallow grooves, too. Burying the strings in the bridge can hurt the sound more than you would expect.

[jezzupe]

I've always been very sensitive to the spacing of the strings on the nut...too far apart or uneven will drive me "nuts".

A related question to the makers here: have any of you noticed whether or not the depth of the grooves on the nut can significantly affect the tone? For instance, will a deeper groove on the G string create a richer sound? (I apologize in advance if this is a ridiculous question...)

Not only kill the tone , but too deep of nut grooves WILL cause buzzing on open strings

[Brad Dorsey]

IME, you generally get the best sound with the grove depth less than half the string's thickness on nut....

How could the nut groove depth have any tonal effect except on open strings?

[polkat]

I believe he's talking about the open strings. I doubt nut groove depth has much effect on fingered notes, but I can hear the difference on open strings. Has a sort of dulling effect (to me anyway) when the grooves are too deep. You can't see it in my pic, but I cut even a bit less then half the string diameter, but too little and the string can pop out of the groove.

[Fellow]

Have a violin here with a very nice nut on it, well shaped an seemless fit. But, the D string groove is not quite centered and is closer to the G then the A by a noticable difference. I can feel this while playing the instrument. Since the nut is so nice, and my time is often short, I'd rather fill the old groove and recut it, then make a new one. But, what to fill the old groove with? Perhaps a tiny spec of ebony? Epoxy? Anyone here done this? Thanks!

++++++++++

It is too tricky to fill or repair an old nut. Simply make a new one to avoid any complication.

Return the old nut to your customer.

[robertdo]

I believe he's talking about the open strings. I doubt nut groove depth has much effect on fingered notes, but I can hear the difference on open strings. Has a sort of dulling effect (to me anyway) when the grooves are too deep. You can't see it in my pic, but I cut even a bit less then half the string diameter, but too little and the string can pop out of the groove.

There is also the plucking issue. If the string is too near the fingerboard (nut groove too deep) it becomes very difficult to grab the string and pluck it. I also had this problem of the A string being dull and only when I read this forum did I look at the nut groove. And indeed the string was buried too deep. I simply put a small piece of paper and the difference was so clear, the open A string being resonant and ringing again as it should be.