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I was just starting to check my scale length so that I could figure compensation and bridge placement. The scale is 25.4" - I got the fretboard from LMI as well as the Martin style bridge.
My actual distance to the first fret is 1 27/64th, and the plans (same scale length) show 1 26/64th.
Is this enough error to worry about? The rest of the frets are correct. I just failed to cut off enough at the nut end. Now that the fretboard is on the neck, I can't take it to the disk sander and scrub it away. If I do need to take some off, any suggestions on doing that with ebony? I have some files, sandpaper, but not much else.

Thanks for any help,
Bob

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Bob
From the oldest town in Texas.

Stewmac fret calculator shows 1 inch and 27.23/64ths from nut to 1st fret for 25.4 inch scale.
Maybe the plans build in some nut compensation?
Or the plans could be for a martin 25.34" scale (often referred to as 25.4)
That would be 1 27/64"
Anyway, someone may pipe up with cents error for 1/64" difference.
If you want to remove the excess. a sharp chisel vertically down to the neck wood is the way I would remove it.

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

OK, maybe I should just leave things alone. On a little closer inspection, my difference is less than the 1/64. Poor ole eyes can't get any closer even with glasses and magnifying lenses added.
Thanks for your input Colin.

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Bob
From the oldest town in Texas.

Do the plans actually state that measurement?

The plans themselves may not absolutely accurate as they can also expand and contract.

Excellent point. I've got some other accurate scale measurements, especially Colin's, and I am very close to those, so I'm going to let this one go to sleep.

Thanks for all the help, everyone.

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Bob
From the oldest town in Texas.

That went completely past me.
It didnt occour that anyone would measure fret placement from a printed plan......
Ctrl/Alt/Del... [Reset]/[mindset]/[Reboot]...

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The name catgut is confusing. There are two explanations for the mix up.

Catgut is an abbreviation of the word cattle gut. Gut strings are made from sheep or goat intestines, in the past even from horse, mule or donkey intestines.

Otherwise it could be from the word kitgut or kitstring. Kit meant fiddle, not kitten.

I have never seen a set of prints that would allow a person to measure directly off of them . Most include a table with the proper measurements for fret spacings.

Bob: Since you say that all the distances are correct to the drawing except for the first fret to nut, I suggest that who ever did the drawing shortened the first fret to nut to help with intonation especially in the first position.
Tom

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A person who has never made a mistake has never made anything!!!

Not all 25.4" scale lengths are the same. LMI knows what they're doing so I'd leave it alone. I've used their fretboards before and never had a problem

maybe a tad cryptic ...?

1/64 of an inch eh...best just chain saw it off and be done with it.

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Audiences and dispensations on Thursdays ~ by appointment only.


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Try a file with an edge ground flush, or sandpaper glued to a stick. Agreed that it sounds like the plans included a small amount of nut compensation, which will help the first frets play in better tune. It wouldn't hurt to take off that 1/64th, but zillions have guitars have been built without nut comp.

I've gotten best intonation with LMI cut fingerboards by taking 20-30thou off the ends. Nothing wrong with them, they just don't pre-cut them with nut compensation (thank goodness).

Greg: There is a bit of built in compensation..........................1/2 the fret slot...!! Or at least on the pre-slotted ones I have received from LMI. There is a fret slot at the nut position. Agreed there should be a bit more.
Tom

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A person who has never made a mistake has never made anything!!!

Yeah, that is true, 1/2 a kerf slot! The first guitar I made with an LMI slotted board I just left it as is, but eventually went back later to dial it in with a digital tuner. In practice it seems it takes a touch more than .011" to get things perfect - or at least pretty good.