Acoustic Guitar Construction

I buy my templates here but have a jig to cut them on the table saw.

http://www.aiguitars.com/luthiertools.htm

They are within .005" to the best of my measurement.

I have always wondered we set them as accurately as we can, either as part of the build or later someone crowns them with a file, easily moving the crown a bit.

Well Will, I saw them by hand within 0.008" (0,2mm) error. If not, I fill the gap and resaw it. The guys who play my guitars make remarks about the accuracy of the pitches. So I guess it is within the space "normal" people can hear. I made a "devise" that I clamp over a pencil mark and let the saw sit on top of it as accurate the eye sees it.
I''ll post a pic tomorrow.
Herman

Always the discussion of how many cents off a man can hear.
Here is a site where you can test yourself.You can choose the amount of cents. For us the 2 and 5 cents test is most interesting. Use one speaker, because a stereo set may give a false result. FWIW: I can hear the 5 cents off. 2cts off is the same to me.
My 2cts, LOL
Herman
http://www.audiocheck.net/blindtests_pitch.php?cent=5

I can hear both the 5 and 2 cent differences. Now, if I could only play music well.

I am blissfully deaf at those levels. No wonder music sounds so good to me!

The test is not really testing your ability to hear intonation in a guitar. A better test would be a tone against the harmony notes in a cord. Or even two tones, the tested note against a harmony note and even a octave.