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Hello all. Long time reader, first time poster on this forum. Lots of great information to be found.

I've been struggling with this wrt neck angle in guitars I build: some sources suggest a straight edge on the fingerboard should land just over the bridge at saddle location, while others suggest the same, but for a fretted neck. Seems to me there would be a good difference between both... Am I missing something?

Thank you!!

Welcome to the party

Frets are typically about .040" or 1mm tall, and that can be accounted for by differences in preferred action height, neck relief, amount of saddle exposed above the bridge, whether "just over the bridge" means .002" or .020", soundboard stiffness (pull-up under string tension), and so on.

But for the most part, either should work. Which one you choose will affect your string-height-at-bridge and the amount of saddle exposed above the bridge. 1mm + or - on the string height won't make a big difference in tone or soundboard stress. And 1mm + or - on exposed saddle won't break the bridge or make it impossible to adjust the action low enough. Once you see how it turns out, you can adjust on the next one by changing the projection height or the bridge thickness or both.

FWIW, I go for the higher one (more exposed saddle). Un-fretted board a bit over the bridge.

Thank you, Dennis! That makes a lot of sense. What do you use for a standard bridge height as a point of reference to set the angle, then?

I generally use an 11/32" (0.344") bridge, and set the straightedge at 0.390" above the top. The straightedge is placed on top of the frets, on the centerline of a radiused fingerboard. That is 0.046" above the top of the bridge. Without frets, which are usually around 0.040" tall, that places the straightedge about 0.006" above the bridge.

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John

Thanks (again!) very much, John, for the great information. I jotted all of this down and will keep it handy.

Is that irrespective of scale length? For a 000 with a 24.9 scale for instance, do you keep those same numbers?

Thanks so much

Phil

You're thinking in the right direction. When you measure relative to the bridge, then the bridge thickness (along with all those other small influences I mentioned before) indirectly determines your string height. John's numbers are good. Use them.

I don't have a standard bridge thickness because I don't have a standard string height. Always experimenting

I don't reference the bridge but rather the height of the strings off the top at the bridge position. I try to keep that between 7/16 ths and 1/2 inch (10 -12 mm). I then set the neck to give the desired action at the 12 th fret. There are many ways to do it, so pick the one that makes the most sense to you.

Roughly speaking... [WINKING FACE]


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This subject came up in March of 2013, and I happened to be working on my tax return at the time. After struggling with some of the tax forms, I posted my take on the form they would create to answer this question:

1. Scale length.
2. Fret height.
3. Bridge height.
4. Body width at widest point.
5. Add line 2 and 3.
6. Subtract line 5 from line 1.
7. If line 6 is less than 0, go to line 14.
8. If line 6 is greater than 0, subtract line 6 from line 4.
9. Multiply the square root of line 8 by the reciprocal of line 2.
10. If line 9 is less than 0, go to line 14.
11. If line 9 is more than 0, go to line 13.
12. If line 9 is 0, go to line 13.
13. The straight edge, laying on the frets, should be just a skosh above the top of the bridge
14. You have the worlds smallest Ukelele.

John's answer is much simpler, and much more accurate.


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Yes.

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John

I must admit I make some allowance for "pull-up" of the top under sting tension, (usually about 0.5 to 0.75mm depending on the stiffness of the top) and aim for a final string height of much the same, around 12.5 - 13mm.
(Don't mean to nit-ick, but 7/16th to 1/2" translates to 11.1 to 12.7 mm in real money )

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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.