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Can anyone help me? What would be the Distance from the nut to the saddle, when the 12th fret meets the body of the acoustic guitar? The guitar would have 19 frets, can anyone help please.

It would depend on the scale length. The 12th fret needs to be at half of the length of the vibrating string. The length of the vibrating string is scale length. This is not a constant and will vary by guitar type and model.


Measure from the fret board edge nut to the middle of the 12th fret and that will be half of the scale length. Double this and the measurement will be where the saddle goes theoretically. In reality you add a bit of distance to the theoretical scale length in order to compensate for a tendency of the guitar to play sharp. Add this distance on the saddle end of the string. 1-2 mm for a classical and maybe an 1/8th inch for steel string. This will get you close but there may be other factors involved. Compensation can also be created at the nut but that is less usual.

Hope this helps!

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http://www.booneguitars.com
https://www.facebook.com/pages/Stephen-Boone-guitar-builder/488208541257210

What Stephen said, and I would add that the number of frets has no bearing on the nut-to-saddle distance.

Pat

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formerly known around here as burbank
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http://www.patfosterguitars.com

The Martin 12 fret 000 is very close to what you are describing- 20 frets instead of 19, but you
could either make the fingerboard a little shorter, or modify the body and scale length a bit
to fit 19 frets to the edge of the soundhole. The 12 fret 000 has a 24.37" scale length (I'm
building one right now). Here's a picture of a 12 fret 000 from the Martin Custom Shop.
These plans are available from Steward Macdonald as their "000 Guitar Plan".

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Gene

Politicians and diapers must be changed often, and for the same reason- Mark Twain

Try using StewMac's fret calculator: http://www.stewmac.com/freeinfo/Referen ... tcalc.html

You will need to know the scale length to use it. Provides "average" values for compensation for each string to get appropriate saddle location.