Nut Materials: Stone?

[Clicker]

I did a search but my terms may have been off somewhat.

In relating to what Roger Siminoff has written about the density of the nut/bridge materials, (and that to suspend a string between two pieces of concrete would improve the sustain,) why not just make them out of a more dense material than wood? Electrics (guitars) have the metal bridges but why not metal nuts?

If ebony or other hard wood is sought out for the nut material couldn't a material like flourite be used? As far as the materials hardness is scaled, it's rated just above those minerals you can scratch with a fingernail.

I borrowed the image from an ebay listing I bid on.

-harry

[Bill Snyder]

Nuts are rarely wood on mandolins. The bridges are but not the nuts.

[Clicker]

Nuts are rarely wood on mandolins. The bridges are but not the nuts.

Quite right. My ignorance is showing ... again. But the questions still stand. Instead of bone then why not fabricate nuts out of a substance that lacks the propensity to float in water, i.e., less porous? -h

[Pete Jenner]

Sorry wrong thread.

[UncleNorm]

Do you want sustain or quality of sound?

[Bill Snyder]

You do not use the porous part of the bone for nut blanks. They need to come from large, dense bones. They do not float in water.
Clicker, bone is chosen because it works and works well. It will last for decades. It tends to get high marks for tone and it is easy to work with. If the stone you choose will do all that it too will be a good choice.

[sunburst]

Redundant post removed. Two posts showed up while I was typing.

[Pribar]

I have made guitar nuts out of several types of stone and crystal, (obsidian, polished granite, marble, quartz etc) and they all share one thing, they are incredibly hard to work. When I am making one as a customer request I can bill for the extra work, otherwise it is bone for the simple reason it works and is relatively easy to shape. Also the obsidian and marble both failed, the obsidian chipped then shattered under the vibration and the marble eventually crumbled.
Don't get me wrong, experiment away it is the only way you find if something works, the fact is bone is widely used is because it is cheap, available and can be easily shaped.

[Marty Jacobson]

Reconstituted stone can work (it's similar to Corian), but there is a wide variety of "recon stone" products out there, some are resin with a little stone and some are stone with a little resin. The brand I use from Masecraft works fine, pretty similar to bone and maybe a hair denser.
Without a lapidary setup and an army of diamond files, I don't see how you'd get a good-looking nut out of that gemstone, Clicker. It is an interesting idea, though. If you are a "rock guy" and have lapidary wheels, go for it. Otherwise it's really not worth the effort.

[Bertram Henze]

So many inventors of the perpetuum mobile out there...

Sustain is the time it takes for the string to lose its energy - where does the energy go?
1 - into vibrations of the air, a.k.a. "sound"
2 - into heat, via damping materials

The louder an acoustic instrument is, the faster the strings lose their energy, the shorter the sustain; for examples, see
- upper end of acoustic volume spectrum: banjo
- lower end of acoustic volume spectrum: electric guitar

Assuming you don't have any damping materials on your instrument, that's the bargain you cannot escape. Any material that will increase the sustain must lower the volume. If it is sustain you're after, get an electric mandolin; magnetic pickups hardly draw energy, they function merely as a signal to the amplifier, where the real acoustic energy is prepared.

[Pete Jenner]

Pribar, have you tried glass. If so does it shatter like the stone?

[DerTiefster]

Bertram: as you say, the vibrational loads are sound and heat. One you want, the other is parasitic. For a given volume, you would like (for argument's sake) to reduce the parasitic load to increase sustain. That's as far as you can go w/o sacrificing volume. A more massive mounting (nut) will reduce the vibrational energy coupled into the relatively useless neck vibration.

I might guess that a tungsten nut would be a great experiment. It's about as far as you can go in the density direction, it's tough, and it should tell you whether anything can help with increasing sustain. Bronze wouldn't be too far behind and is more readily worked and available. Might be fun. I won't be trying it myself, as I have too many other experiments to do.

On the bridge side, you need something that will move enough to couple the vibrations into the sound board. Go too far in the density direction there (say, the infinitely dense "unobtainium") and the strings will vibrate essentially forever, but you'd get no sound board motion and no sound. Stiff materials of appropriate density are called for there to couple sound in to the sound board. But an immobile (inertially confined?) nut isn't at first blush a bad idea unless you really like the fast decay of some instruments and styles.

[EdHanrahan]

Let's recall that back in the '80s or so, lots of brass nuts were installed on electric guitars, and a fair number of accoustics, because it's harder and denser than many of the nut materials in use at the time. The (non)success of that effort is apparent by looking around today. (My own suspicion: I doubt that few with bone-nutted instrument seriously considered switching to brass).

I'm also guessing that, whether brass, bone, corian, or whatever, it's good for the nut be softer than the string that it supports or you'll end up wearing thru strings pretty often - maybe weekly. Far more convenient to wear out the nut itself every three or five decades.

[Pribar]

Pribar, have you tried glass. If so does it shatter like the stone?

The only two that I know failed were the obsidian and the marble, the marble one I knew was going to fail because of how soft it was while carving it, but the customer wanted to see if I was wrong so...
The others might have failed over time but if so they haven't been brought back in to me, I get a lot of requests like these because of the nearby colleges and university, students will buy a cheap rogue or silvertone guitar and bring it in to be "customized" by a coupla cheap add ons or some other add on (like a nut and saddle made from their birthstones etc)
as far as a glass nut, I don't know, buy a cheap set of diamond files and a grinder attachment for a dremel and find out if you wish, please let me know how it works if you do so I will know whether its worth the time if I ever get that particular request

[Pete Jenner]

Ha me try it? I thought you might. I've been thinking about doing it for a while. I've got one of those glass grinders for doing leadlight windows somewhere. I've only made 3 nuts and they were bone but I may just give it a shot as soon as I get a round tuit.

[Bertram Henze]

A more massive mounting (nut) will reduce the vibrational energy coupled into the relatively useless neck vibration.

I guess even after acoustically disconnecting the neck from the nut (don't know how far that can go), the neck is still connected with the body and will therefore vibrate nevertheless.
The other thing is: would the nut still make a difference if we played fretted notes? Because only then would a vibrating neck leak power to a "parasitic" sink - the fretting hand.

Can we further complicate this by assuming we have a zero fret?

[DerTiefster]

I forgot about zero frets. I knew nothing about brass nuts on electric guitars. I was trying to point out a way someone could push toward the extremes of nut(ti)ness in experimenting with nut materials, and that the gain appeared small but using a tungsten nut in comparison might let you see if -any- difference could be heard at all. I wasn't certain any practical change could be made. Because (I thought) the issue of bridge material was raised, I thought I'd mention the bad effect of going to the limit in hard, dense bridges: no sound, but great sustain. Didn't seem desirable.

[Jim Rowland]

Install a good zero fret and you can use most anything will hold its shape for the "nut". It will change the sound of your instrument for sure. Maybe you would like it and maybe not.
Jim

[sunburst]

All of the vibrational modes of an instrument will be set in motion any time it is played. The main one moving the neck is the main full body mode, where the entire thing moves kind of like a marimba bar. That will happen regardless of the nut weight, though adding weight (without adding stiffness, as a nut would do) would lower the frequency of the mode. The amount of weight variation available in something as small as the nut wouldn't amount to much compared to, say, a heavy set of tuning machines and/or a heavy clip-on tuner.

But back to the OP. Bone is inexpensive, easily worked, does the job well, lasts a long time, and is tried and true. Why use something else other than looks?

[Lefty Luthier]

I am surprised that pearl nuts haven't been mentioned. Many top end mandolins use them. The main benefit that I see in bone is that it is more resistent to chipping on the outer edges; not that it is either better or worse than other materials such as pearl or stone.

[Charles E.]

MOP makes a great nut, it is harder then bone and looks great. Another material would be carbon graphite but for some reason it is not used.

[mirwa]

We use primarily bone, simply becuase it is readily available and easy to work, but we have made nuts from corian, plastics, wood, and yes stone, each to there owner represented a difference, to us it was questionable.

[Clicker]

Do you want sustain or quality of sound?

I want an infinite amount of both so, what'cha got? Since the "quality" of sound is a continuing nightmare of what ifs, I'd have to vote for sustain. You know, that kind of sustain which keeps the tone wood vibrating even as the next note is struck. -Harry

[mirwa]

If your after sustain, then fit heavier tuner heads on, clamp a small piece of wood under the headstock, there are many ways to increase sustain, the nut IMO would be the least of all these, as the weight difference between each type is fairly negligible except for stone.

[Willie Poole]

I try to play by hitting very few open strings so why not make a nut out of stainless steel or whtever the frets are made out of, some people capo up a mandolin and that makes the fret act as a nut and I haven`t heard if that changes the sustain or sound....I know most guitars still sound as good capoed as they do uncapoed....I guess that would be much like a O fret....

Willie