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I'm just getting ready to glue the back on three classical guitars. For setting the neck angle, I glue the back so that a straightedge placed down the neck (with the fingerboard on) will be 6mm high above the soundboard at the location of the saddle. What are some of the other techniques used to make sure the neck angle is properly set when gluing the back on?

Thanks!

John

I do it the same way, but use a .175 shim at the 12th fret location and a .040 shim at the 1st fret location to get a straight edge height above the sound board that equals whatever my finished bridge/saddle height is going to be. 12mm or so. 8mm bridge and 4 mm saddle +- depends on how I feel. Eventually I'll establish my "standard".

Once the top deflects with string tension I'm looking for about 4mm at the 12 fret for string height.

That's pretty much it, except I use David Schramm's technique of putting 2 2.5lb weights on the upper bout to simulate the effects of string tension. Use the back strip on the back to lock in the slipper foot. Every guitar I have built using this method comes out with perfect action.

John,
Neck angle is a very intersting question. Take a look at most higher end Spanish guitars and you will notice that the neck on the nut end is pushed forward anywhere from 1 to a few millimeters. Flamenco guitars have the neck pushed forward even more. I shoot for a 5mm gap at the bridge location. This includes the fretboard. You could also get this gap by planing the fretboard instead of pushing the neck forward.

[QUOTE=Robbie O'Brien] John,
Neck angle is a very intersting question....... You could also get this gap by planing the fretboard instead of pushing the neck forward. [/QUOTE]

Yup, just like that obscure luthier Antonio de Torres did! Fret board 6mm at the nut 4mm at the soundhole.

Colin

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