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Hi folks,

Question about the quality of bone used for making nuts / saddles and also maybe a cautionary tale about material storage.

First, the issue - the nut slots are grabbing on a guitar. There is near zero chance (I think) it is binding on the walls of the slot. Reason I say that is I use SM gauged nut files that are sized for medium strings and then put lights on the instrument.

There is no sonic issue (sitar, buzzing, etc….)

They just hang when tuning like they are binding, but I cannot see how.

Is it possible the bone is low quality (soft) and the strings are digging in?

I bought a batch of 20 nut blanks from a supplier that is not my normal supplier. My normal supplier is StewMac and wherever they get their material. This new supplier was recommended by another builder. The quality looked fine, bleached white, not crazy porous or anything. So I threw them in with the rest of my stock. I cannot tell which is which but I’m wondering if this mystery batch was lower quality than I initially thought.

Brad


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I should add that it is any string, not specific strings. Like it’s not the D/G exits to the slots are binding. Even the E and that sucker is half in half out.


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If you have something with a fine sharp point, you can scratch it along the bottom of the slot and feel if it’s rough. I use the StewMac files, too. Sometimes, I get a rough bottom in the slot that I have to chase with an abrasive cord. I don’t know why. Maybe I have some bad blanks as well. I usually got mine from LMI and stocked up in their closing days. I think you can compare softnesses by dropping blanks on a concrete floor and listening. You will hear differences.

It's possible the nut material is soft. This is why I tap my bone nuts together. I want to hear a high pitched TINK. Then I know it's good stuff.

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"Act your age, not your shoe size" - Prince

Yep not all bone is equal.

Dave and I used to process our own and still do some of the time because we want bone that is more dense and less porous. It's no fun when you're one or two swipes away from finishing that nice, new, hand crafted nut and a void is uncovered. That happened to me once *&%%^&^%$

We joke that we use quality bone from cows who are permitted to free range using their legs and cows who do yoga so their bone is more dense.

Bleaching does slightly soften bone so we prefer unbleached bone and there is also risk of getting bone that has not been degreased properly.

We have not resupplied in a while but Christie Song was/is one of our goto places for decent bone and she never let us down. We process our own too for pieces that we need that are larger than what we can get in blanks.

Even quality bone will dent over time. Some of my living room guitars may not get played for a year and the strings begin to cut into the bone over that time.

So try some nut lube which one small container has lasted me nearly 20 years now. Nut sauce is another brand. Just lift the string, use a cut-off from a 0.010" string to dip in the stuff and then distribute it in the slot. Replace the string and tune a bit up and down to distribute and wipe the excess off.

Lastly bone that has not been degreased properly will be soft too so it may not be a density problem Brad it may be the stuff was not processed well and is too greasy. This suggests that you could take what you have left that is questionable and degrease it yourself and then use it. Soaking in white gas is one method.

And really lastly the 1/2 string proud of the nut top is a legacy thing that we know who started it and it's not only not necessary it tends to distract people from how the nut should be set-up and that is with the slots cut as a function of how we cut nut slots to be low not as a function of 1/2 proud of the top of the nut. There are a lot of myths in Lutherie that often started back before there were Internet forums, books, etc to learn from.

I've always used the half thickness as gospel. I have to cut a nut soon and I will put that myth away when I do.

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Hutch

Get the heck off the couch and go build a guitar!!!!

I drop mine on concrete. If there's no sharp tink, it goes in the trash.

Oddly enough, when we still used ivory, when I did that drop test, it made a much softer tink, but i never had that problem with it. I miss that material. So much more pleasant to work, and sometimes had beautiful grain.

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formerly known around here as burbank
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