Zero Fret Nut position

So here is a technical question or more correct, conundrum.

It is a common claim that the zero fret configuration, apart from making for a great action also provides more accurate intonation. Is this because the point of string contact is in the centre of the slot and not the front edge as on a nut only configuration? If this is the case, then shouldn't the position of a nut only set-up be the first fret distance + half the fret slot width?

This makes sense doesn't it?

Answers below please

The way I see it Pete is that it makes no difference if the string is coming off a nut or a "zero" fret in terms of intonation. The scale length should be identical. Therefore a zero fret can't make "better intonation". That presumes that the height of the two would be the same in terms of string action.... As for providing better action, I don't know about that. I just know that on cheaper commercial guitars, the zero fret was usually indicative of a cheaper build. I guess they thought they could get better predictability with a zero fret than variation in nut slots and thus more accurate intonation in a mass production setting. .... This is a HUGE area of discussion in the guitar world. Me, I never really cottoned to the idea of the zero fret, but what do I know? And I never tried doing one. Also note that zero frets are absent in most higher to high end guitars. There is a reason. The last guitar I played with a zero fret was a 60's acoustic (!) Fender and it was a dog all the way around. Played and sounded horrible. Probably worth a fortune now.

I dont do zero fret jobs, but if I did it would be something like this...but done with standard fret wire. zero fret by Ken Timms, on Flickr

Thanks for your answer sequoia. It is, however, a response to a question I did not ask. I get near perfect intonation with no compensartion either at the nut or at the saddle. I have refined the saddle position over the last 23 years and found where it sits best. I was postulating on the difference 0.3mm might make to further accuracy.

Second - the zero fret was favoured by many respected luthiers - Mario Maccaferri comes to mind and he was no slouch when it came to innovation. In the electric guitar field a guitar under the name 'micro-frets' allowed adjustment of string length at the nut and many classical guitar makers have also looked at this.

I spent a year and a half curating an acoustic musical instrument collection in Ohio in the late 90s and have seen more instruments , guitars and ukes in all their iterations than you can shake a stick at. This is simply one thing I never considered at the time but I am sure those builders who I saw using a zero fret were anything but producers of cheap instruments.

Authoritative statements need to be backed up by empircal evidence usually... here it seems on this forum that 'If I say it, it must be right' eh?

I don't think placement affects intonation. You mark out your fretboard and the O position becomes either the face of the nut or the crown of the zero fret. So both are in the same place a terminators of the string.

Where a zero fret can help with intonation is in ensuring that the action at the 0 position is at the correct height. Careful builders set this right when they cut nut slots, but lots of manufacturers send out instruments whose nut slots are not deep enough. This causes intonation issues at the lower frets.

It's not possible to set a zero fret too high (unless you choose huge fretwire for it), so this potential problem is avoided.

So what you are sayingChris it doesn't matter if the ditance from the nut tothe first fret is shorter than the calculated distance?

With my limited understanding...
The nut is only acting as a spacer. The scale length starts at the crown of the zero fret.

Stagehand said:

With my limited understanding...
The nut is only acting as a spacer. The scale length starts at the crown of the zero fret.

Click to expand...

That is my understanding too. Why would the nut distance even matter since the string should only vibrate between the zero fret and the saddle?

I am watching this thread with great interest, since I want to finish my current build with a zero fret.

Why is a zero fret associated with better intonation? Because many builders (especially mass builders) are TERRIBLE at placing the nut accurately.

By using a zero fret (especially if its cut on a CNC machine) the placement isn't subject to the vagrancies of how well someone measures/finishes the fretboard.

The centre of the zero fret or the inside surface of the nut should be in the same place.

I agree that a zero fret should make no difference with intonation, provided that the nut end of the fretboard is exactly square and cut off to exactly the right length, since the face of the nut which sits against this end of the fretboard will determine where the string starts vibrating. That being said, building with a zero fret (I have always done so) makes setup so much easier (no filing of nut slots, ooops, too deep, ...) and makes placement of the nut end of the string so much easier since one is not cutting off the fretboard to just the right length. It is somewhat unfortunate that a zero fret got a reputation for being 'cheap' because of cheap imported instruments. It really makes life much easier and more accurate. [Note: the way that LMI now cuts their fretboards does not directly permit a zero fret.]

Pete Howlett said:

So here is a technical question or more correct, conundrum.

It is a common claim that the zero fret configuration, apart from making for a great action also provides more accurate intonation.

Is this because the point of string contact is in the centre of the slot and not the front edge as on a nut only configuration?

If this is the case, then shouldn't the position of a nut only set-up be the first fret distance + half the fret slot width?

This makes sense doesn't it?

Answers below please

Click to expand...

With respect I really struggled to ‘get’ what you’re trying to say too so I can understand why you have received answers that you feel don’t address the question you asked.

As far as I know there is a common claim that the zero fret improves things.

As far as I know and have seen the slot behind the zero fret has nothing to do with action or intonation. To me its seems to be there to provide sideways support to and containment of the strings. I would except there to be some side clearance between the strings and the slot.

Though I think that I know what you’re trying to say with respect to centre distance I’m not completely certain so I’ll word things differently. I would expect the centre (or rather top point) of a zero fret to be in the same location as the front edge of a traditional nut.

For what it’s worth I used to think that zero frets were a good idea, and then I played a uke with one; I disliked the (high and fixed) action and wasn’t happy with the way the strings sat on the zero fret due to the potential for damage/wear between them. That’s just what I thought and I’m a ‘nobody’.

Ok - Zero fret presents a contact point that is directly in the centre of the slot. A nut sytem has its contact point on the front edge of the saw slot... My question is should there be compensation for this shortening of the distance between the net and the first fret ie, adding half the width of the saw slot to that distance? I'm not talking about the zero fret set-up. I use this to illustrate how this sytem gives a contact point for the string in the centre of the slot and the nut only style moves this point forward by half the slot width... This is commmonwherre most of us start our concert scales at the 2nd fret of the tenor scale. Get a tenor blank out, cut off the first two frets and you have the concert scale length. If you increase the string length by half the fret slot wodth you are messing with the logarythmic calculation for fret distances...

I had hoped John Colter would pitch in here. He has a kabossi with a fret board spaced to the rule of 18, no compensation and it plays perfectly in tune. By all the laws of physics it shouldn't but it does....

Hi Pete, I have just typed out a long, detailed reply, only to be told I was not logged in. When I logged back on, my message had gone! Using the rule of eighteen to determine the placement of the frets does give the required amount of compensation. It is "built in" to the calculation. My Kabosi Uke doesn't use a nut, in the conventional sense. There is a spacer for the strings, but it is somewhat set back towards the tuners.

As I see it, a nut or a zero fret can give equally good intonation. I don't consider one to be inherently better than the other, but I can see why some folk might have a preference - either way.

Does 0.3 mm variation in fret placement make a difference to intonation? Well yes, it must - if measured on a highly accurate electronic rig. Can the human ear detect that difference. Mine can't. However, if the adjacent fret was 0.3 mm out in the opposite direction, I'm sure the result would make most of us cringe.

John Colter

Pete Howlett said:

Ok - Zero fret presents a contact point that is directly in the centre of the slot. A nut sytem has its contact point on the front edge of the saw slot... My question is should there be compensation for this shortening of the distance between the net and the first fret ie, adding half the width of the saw slot to that distance? I'm not talking about the zero fret set-up. I use this to illustrate how this sytem gives a contact point for the string in the centre of the slot and the nut only style moves this point forward by half the slot width... This is commmonwherre most of us start our concert scales at the 2nd fret of the tenor scale. Get a tenor blank out, cut off the first two frets and you have the concert scale length. If you increase the string length by half the fret slot wodth you are messing with the logarythmic calculation for fret distances...

I had hoped John Colter would pitch in here. He has a kabossi with a fret board spaced to the rule of 18, no compensation and it plays perfectly in tune. By all the laws of physics it shouldn't but it does....

Click to expand...

To me, in such a case, the logical thing to do is to space (shim) the nut back from the edge of the shortened fretboard by half the width of a fret slot. That would maintain the expected relative positions.

Pete Howlett said:

Ok - Zero fret presents a contact point that is directly in the centre of the slot. A nut sytem has its contact point on the front edge of the saw slot... My question is should there be compensation for this shortening of the distance between the net and the first fret ie, adding half the width of the saw slot to that distance?

Click to expand...

Ah, got it now!

In theory the zero fret should be a fraction more accurately placed, but ...

The slot is only 0.3 mm so the misalignment is only .15 mm. Less than 1% out, so I can't hear that!

Also, the theory of nut compensation suggests the contact point for string termination should be nearer the bridge,and thus that theory says the nut is more accurate. But again by less than 1% of a semitone.

I think we're discussing angels dancing on a pinhead here And I slot my frets by hand, so ...

Here's the guy to ask about fret slotting accuracy, the Hofner Beatle bass:

https://youtu.be/HfaQVn3fGHw?t=8m36s

Even uses a zero fret.

Oh just noticed, it's a larger fret wire than the rest of the frets

ProfChris said:

Also, the theory of nut compensation suggests the contact point for string termination should be nearer the bridge ....

Click to expand...

If you know of one I’d be very interested to read a simple explanation of that, please.

At last - someone who can read my mind. It's 2%. Slot width is 0.6mm. Thanks. For peace of mind and because i can do it now I have my CNC machine and it has earned its cost producing my rosettes and pearl logo, I can go ahead and program my fret boards with the plus 0.3mm knowing that it 'does not matter' whilst at the same time believing that I have done the right thing. I'll let you know if it changes anything.

I'm also pleased to know that it is hard to 'hear' such subtle changes 'cos I thought it was just me. It's like the arguments surrounding string height at the 12th fret and string height at the 1st fret. I believe for playing comfort, the latter is more critical. However because of received wisdom generated by the number of times it is referred to, discussed and mentioned on videos posted on the internet, height over the 12th fret is seen as crucial. It's not uncommon for clients now to request an action of 2.25 mm over the 12th fret on a ukulele. This makes fan strokes and other strumming styles 'noisey' and is very time consuming to achieve with fretboard relief playing a crucial part to getting this right. The related flamenco guitar (it is a principally 'strummed,' nylon strung, lightly built, fretted acoustic instrument) has a playing action of 4mm over the 12th fret... As much as I blench mentioning the 'G' word here to somehow justify my argument for a sensible action- remember my oft stated mantra "Guitar making is not ukulele making", it is the only empirical reference point I can quote apart from my years experience making tenor ukulele. Must first instruments, commissioned by a Hawaiian store, made for Hawaiians, specified by an authority on ukulele who subsequently went on to advise a number of manufacturers of ukulele specified an action of 3mm over the 12th fret on his ukes.

I know we have evolved and hence I am at a point where I am thinking, 'Is there any more I need to know?'; it's why I asked the question to see if minds greater than mine could justify my thinking for me. So thank you for your comments. I'll make the change in the next month or so (I am no longer going to hand cut my fingerboards now I have amachine that can do it) and let you know if that 2% matters

Pete, I can't help but feel that this "error" is in your head. People in the know have always measured from the inside surface of he nut or the centreline of the zero fret. Mind you. This probably does explain to some extent why zero frets work. In a World so lacking in theoretical understanding of the issue, using a zero fret leaves MUCH less room for error.

anthonyg said:

Why is a zero fret associated with better intonation? Because many builders (especially mass builders) are TERRIBLE at placing the nut accurately.

By using a zero fret (especially if its cut on a CNC machine) the placement isn't subject to the vagrancies of how well someone measures/finishes the fretboard.

The centre of the zero fret or the inside surface of the nut should be in the same place.

Click to expand...

Exactly. Well said.