Building up the nut

[fdeck]

Three nuts in my house (bass, cello, and daughter's 1/4 size violin), all have nut grooves that are worn too deep. Is there a simple way to build up the grooves, even on a temporary basis, short of replacing the nut?

[bassteban]

A luthier once told me to apply superglue(CA)to the low slot- remove the string(s)first of course- and file/sand to the proper shape. This method fixed a cheap classical's G string slot and has been stable for several years.

[1st Bass]

The cleanest way to do it is to remove the nut and add a thin ebony shim under the nut, to raise the bottoms of the string grooves to the correct height...then file the top of the nut down so the grooves aren't swallowing the strings.

However, it was pointed out to me some time ago, by one of our members from the land of Oz, that black tagboard (or the like) underneath was just as effective, and much easier.

Either way avoids the superglue, which I personally feel is a good thing.

[George700DL]

Originally Posted by fdeck

Three nuts in my house (bass, cello, and daughter's 1/4 size violin), all have nut grooves that are worn too deep. Is there a simple way to build up the grooves, even on a temporary basis, short of replacing the nut?

What 1st bass suggested is better than what I'm about to write, but since you're looking for a temporary solution, I just did this on my viola after reading about it in various places - superglue+baking soda. Here is what I did:

1. Take off strings
2. Clean the groove (remove grime, pencil graphite, etc.) I used #320 sandpaper, just folded to make an edge that goes into the groove.

3. Get baking soda ready (meaning, be ready to grab a pinch in a matter of seconds)

4. Put a drop of superglue in the groove, then add a little baking soda. I just used a tip of a knife, then pressed the powder in. It will harden instantly.

5. Let it sit for a while, then create a new groove as you need.

This definitely worked for me. I was in a hurry and needed my viola, which had lately developed a buzz on the open A string - it almost sounded like a sitar. The superglue + baking soda solution has so far lasted for close to a week, which got me through, but of course I plan on knocking out the nut and installing a new one when I get a chance.

George

[Cody Sisk]

Originally Posted by George700DL

What 1st bass suggested is better than what I'm about to write, but since you're looking for a temporary solution, I just did this on my viola after reading about it in various places - superglue+baking soda. Here is what I did:

1. Take off strings
2. Clean the groove (remove grime, pencil graphite, etc.) I used #320 sandpaper, just folded to make an edge that goes into the groove.

3. Get baking soda ready (meaning, be ready to grab a pinch in a matter of seconds)

4. Put a drop of superglue in the groove, then add a little baking soda. I just used a tip of a knife, then pressed the powder in. It will harden instantly.

5. Let it sit for a while, then create a new groove as you need.

This definitely worked for me. I was in a hurry and needed my viola, which had lately developed a buzz on the open A string - it almost sounded like a sitar. The superglue + baking soda solution has so far lasted for close to a week, which got me through, but of course I plan on knocking out the nut and installing a new one when I get a chance.

George

I do this same method with ebony sawdust, works just as well..

[George700DL]

Originally Posted by DallasStrings

I do this same method with ebony sawdust, works just as well..

The ebony dust mix probably lasts longer than the baking soda thing.

I'm no chemist, but I think the purpose of the baking soda is to speed up the curing time. In my case, the baking soda took curing time from 30 seconds to about 2. I couldn't believe it. It's very brittle in the end, but I seems to work well for groove filling.

[ZolkoW]

Originally Posted by DallasStrings

I do this same method with ebony sawdust, works just as well..

yeah, ebony sawdust (if available) with CA is probably some harder than ebony itself.
and it's invisible in an ebony nut.

[Cody Sisk]

Somehow the ebony dust will speed curing just as well as baking soda. I'm no chemist either, but when I try the same method with maple or spruce dust, it just turns into a muddy slurry that never dries..

[PB+J]

It's an acid/base thing. The baking soda shifts the PH to basic and the superglue cures instantly. I have a spray can of stuff designed to make CA glue cure instantly. It's amazing-put some glue on, spray--instant cure. Lots of heat too--a flash of heat while it cures.


You can find gel super glue--Gorilla glue makes a thicker super glue that is very tough. I've done the sawdust/super glue thing many times and it holds up very well. I even used it to fill grooves in the fingerboard of an old Kay I used to have. Bass had been used by a guy in a polka band, had deep groves in two or three root-five places. Sawdust, superglue, level with a scraper, sand lightly--worked fine.

[Jake deVilliers]

Originally Posted by 1st Bass

The cleanest way to do it is to remove the nut and add a thin ebony shim under the nut, to raise the bottoms of the string grooves to the correct height...then file the top of the nut down so the grooves aren't swallowing the strings.

However, it was pointed out to me some time ago, by one of our members from the land of Oz, that black tagboard (or the like) underneath was just as effective, and much easier.

Either way avoids the superglue, which I personally feel is a good thing.

+1 This is the only way I'll do it.

CA might be fine if you have a problem at a show but not for a lasting repair.

And I'm sure cardboard is easier but I think ebony sounds better!

[Cody Sisk]

Ya if you have to raise all 4 grooves, the shim underneath is the way to go. I have black fiber board in .3 .5. .8 and 1mm thicknesses for such purpose. It's a whole lot less work than the ebony/CA method. Though if I have to fix only one string groove, I'll fill with ebony/CA, grind it down, smooth it out and carve a new groove. The patched ebony/CA is invisible when I'm finished and I believe it to be stronger than the original groove.

[james condino]

I'd rather have a shim underneath the nut as described above. If I don't have any material that is the same as the nut- like ebony or rosewood, I try to use the same material that the neck is made out of for the substrate material. The popularity of the baking soda and superglue trick primarily comes from the guitar world where the nuts are made of bone or a similar material. The baking soda color matches pretty easily and it is fast. It has been my experience that anything applied to the actual nut slot works as a temp fix, and will fall apart over time. A thin shim of paper under the string in the nut slot will also work as a temp fix. SOme poeple also like to cut a large wedge out of the nut and then reinsert a new section and file it out; seems like a lot of work to me....

Whatever method you chose, this is something that you can do yourself. Take your time, read up on some ideas, and empower yourself.

j.

[George700DL]

Originally Posted by james condino

A thin shim of paper under the string in the nut slot will also work as a temp fix.

With the cardboard, you don't have to limit yourself to the nut either:



George

[PB+J]

I would totally agree that putting a shim under the nut is a better way to go. The baking soda thing will work but a shim under the nut is better and more elegant

[forester]

gawd..i thought i made a mild viola arch...
double stop heaven.

[Cody Sisk]

George that picture is sooo wrong on so many different levels! As a former orchestra director, their technique is nauseating. As a luthier, the bridge cuts are laughable. Where'd you come up with that?

[George700DL]

Originally Posted by DallasStrings

George that picture is sooo wrong on so many different levels! As a former orchestra director, their technique is nauseating. As a luthier, the bridge cuts are laughable. Where'd you come up with that?

It's a specialized viola, found pretty much only in Transylvania. You only play chords on it, all 3 strings at a time.

It's held sideways because it's very tiring to play chords for 30-40 minutes straight (1 dance cycle) if it were held in the conventional way.

The bridges must be flat to facilitate stopping all 3 strings at the same time. Specialized instrument for very special music. But I don't mean to hijack this thread further

George

[Matthew Tucker]

George that picture is so RIGHT! its a great picture, i'm wondering what's happening with the couple in the middle! vertical violas, three strings, loads of rosin, looks like a great little táncház ...

[George700DL]

Originally Posted by forester

gawd..i thought i made a mild viola arch...
double stop heaven.

Triple stop, exclusively.

[George700DL]

Originally Posted by Matthew Tucker

George that picture is so RIGHT! its a great picture, i'm wondering what's happening with the couple in the middle! vertical violas, three strings, loads of rosin, looks like a great little táncház ...

I grabbed it from Hungarian wikipedia's description of the chord/rhythm viola.

As for the couple in the middle, it looks like the dude is about to do some sort of a show-off maneuver.

What attracted me to this type of music was the ability to have such huge sound from even just 3 instruments.

But back to the topic - yeah, paper inserts, wedges, etc - you see those types of quick fixes all the time when time is tight.

George