Acoustic Guitar Construction

How far off is too far off? The width of a saw kerf? (.023") Half the width? Twice? I've searched the forum and cannot find an answer. I'd rather not invest in a costly indexing system for the few guitars I will build in a year if I can get away with a hand made miter box and hand layout with a steel ruler. Here's how I've made some fingerboards for mountain dulcimers. (Ok, not guitars, but accuracy is still required.) I'm still working my way toward my first acoustic guitar.




With this method I hit most slots right on the mark, but occasionally get a slot half a slot width left or right of the mark.

I am thinking you already know the answer to the question -- fret position should be spot on and accurate as possible. Multiple errors further degrades the quality of the sound a given instrument can produce -- you simple cannot hide intonation (off pitch) fretting. .023" the width of the blade is a lot, than maybe compounded? With a tight fitting saw and miter box I have produced spot on FB's -- so maybe the miter box and alignment procedure should be scrutinized? $.02

Hey Jim. I read somewhere that a normal person cannot hear a off-tone-pich of 2 cents.
That for a starting point.
My personal view is not to bother about 0,2 mm off pitch. So imperialist would say 0,01" is ok. But maybe others have a different view.
My experience says it is hard to saw more precice by hand.

Herman

Herman wrote:Hey Jim. I read somewhere that a normal person cannot hear a off-tone-pich of 2 cents.
That for a starting point.
My personal view is not to bother about 0,2 mm off pitch. So imperialist would say 0,01" is ok. But maybe others have a different view.
My experience says it is hard to saw more precice by hand.

Herman

Thanks, Herman. I read that the average person cannot hear 5 cents off-pitch, so 2 cents is definite. What I haven't found the answer to is a way to calculate just how far off pitch x mm (or thousands) of error translates into cents flat or sharp. In other words, when is it still usable and when is it fancy kindling wood? If it's difficult to saw more precise by hand, should I bite the bullet and budget for a nearly $200.00 indexing system such as sold by stewmac or LMI? Are they good enough?
While the average layperson may not hear the small errors in pitch, I would assume that any guitarist who might consider one of my instruments will have an ear that can hear the errors.

yeah -- $200 makes you wonder

or

http://www.cncguitarproducts.com/fret-s ... g-jig.html

I bought the templates and made the jig - not difficult - and have done a few fretboards with it; I'm very pleased.

Jim,
I would recommend you spend the $40 for a templete from LMI and you can adapt your miter box to use it. I am doing that, have made 7 guitar fretboards this way and they have all be right on. All you have to do is put an indexing pin into your box and you are set to go with the template.

Kevin