raising nut or bridge slot

[Mat Roop]

Was just looking at this...

https://www.stewmac.com/video-and-ideas/tool-demo-videos/how-to-fix-a-low-nut-slot-fast/?dlv-emuid=1e1b7751-56a5-4218-b845-fb0741ce22dd&dlv-mlid=0&utm_campaign=NutRescuePowder2024.07.06-e-2024-07-06-AI-send-time&utm_id=0&utm_medium=email&utm_source=attentive&utm_term=Fix+a+Low+Nut+Slot+Fast&externalId=6uObs

I have been doing this for nut slots on violins using ebony dust and super glue...... just on cheap student instruments thinking it would last long but I must say none have come back.

Question I have ... has anyone tried the concept for bridge slots?

[FiddleDoug]

I have done that with bridge slots. I used maple dust and CA glue.

[Andreas Preuss]

I didn’t have a good experience with CA glue with dust on the A string notch. After not too long time the string lapping got loose. 
 

I think in particular high tension strings need new ideas to stabilise the notches in the bridge. 
 

 

[LCF]

1 hour ago, Andreas Preuss said:

I didn’t have a good experience with CA glue with dust on the A string notch. After not too long time the string lapping got loose. 
 

I think in particular high tension strings need new ideas to stabilise the notches in the bridge. 
 

 

CA glue is an acrylic plastic remember, and not very hard, and I have always found that glueing dust together with it like that results in something slightly porous as well as plasticy.  To preserve and repair a damaged nut or bridge, or saddle, you can use CA to glue in a replacement piece of the same type of material it's made from. Maybe to file a V and fit a V shaped piece. 

[Blank face]

10 hours ago, LCF said:

 To preserve and repair a damaged nut or bridge, or saddle, you can use CA to glue in a replacement piece of the same type of material it's made from.

Agree. I'm CA glueing tiny maple slices in worn out bridge slots successfully, also ebony splinters in nuts. Or if you won't bother to make a new nut, a thin ebony veneer can be glued to the bottom of the nut to raise it. If done well, this will be nearly invisble.

[David Burgess]

14 hours ago, Mat Roop said:

Question I have ... has anyone tried the concept for bridge slots?

For bridge slots, I like to glue in plane shavings from a bridge, using a string to clamp and form it into the groove as the glue dries. Trim the excess after drying. In my experience, this has held up to wear better than wood dust and glue.

I haven't tried the NutRescuePowder. Since it claims to contain a lubricant and be very slippery, I wonder if it would have enough friction to prevent a violin/viola/cello bridge from going "kah-wump"?

[David Burgess]

9 minutes ago, Blank face said:

Or if you won't bother to make a new nut, a thin ebony veneer can be glued to the bottom of the nut to raise it. If done well, this will be nearly invisble.

Agreed.

[nathan slobodkin]

3 hours ago, David Burgess said:

Agreed.

Depending on the shape of the sides of the finger board it may be difficult or even impossible to finish the ends nicely after lifting the nut. Also the whole top of the nut has to be reshaped and the grooves refiled regardless. Sometimes this repair saves time but sometimes you might as well make a whole new nut.

[Blank face]

38 minutes ago, nathan slobodkin said:

Depending on the shape of the sides of the finger board it may be difficult or even impossible to finish the ends nicely after lifting the nut. Also the whole top of the nut has to be reshaped and the grooves refiled regardless. Sometimes this repair saves time but sometimes you might as well make a whole new nut.

All true. But usually it's only necessary to raise the nut for a fraction of a millimeter and the board and nut accordingly has the biggest width at the bottom so that it often works better than filling the grooves.

[Nick Allen]

4 hours ago, nathan slobodkin said:

Depending on the shape of the sides of the finger board it may be difficult or even impossible to finish the ends nicely after lifting the nut. Also the whole top of the nut has to be reshaped and the grooves refiled regardless. Sometimes this repair saves time but sometimes you might as well make a whole new nut.

I usually just make a new one these days. It's honestly less work than popping the old one off (fingers crossed it doesn't split anywhere), making a shim, trimming the shim, refitting the nut to the fingerboard end, gluing it back on, trimming it again, doing any fill in the sides that may be necessary, redoing the nut string slots, crowning the top, and polishing. 

I can make a new one in like an hour instead. 

[David Burgess]

5 hours ago, nathan slobodkin said:

Depending on the shape of the sides of the finger board it may be difficult or even impossible to finish the ends nicely after lifting the nut. Also the whole top of the nut has to be reshaped and the grooves refiled regardless. Sometimes this repair saves time but sometimes you might as well make a whole new nut.

Yup. Shimming isn't the answer to everything. It's just one of the tools in the toolbox.