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Does anyone have a source for different scale length/fret spacing measurements? I found an awesome XL spreadsheet form from Tim Mullins' website, but in case there's an error in the formulas (which I doubt), I'd like to check against another source.

Thanks Tim! Here's where I got it:
http://www.mullinguitars.com/calculatin ... tback.html

Thanks! (That's a relief.)

+1 on the stewmac fret calculator. I've used it on all my guitars.
Even used it on the ones with fret measurements in the plan, just
to check the numbers.

_________________
Gene

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

Thanks everyone! I'm sufficiently covered in great and consistent sources now. Much appreciated!

Send me an e-mail an I'll send you back a good Excel spreadsheet...also provides stretch compensation along with the uncompensated output.

stuartgortsr@gmail.com

Anyone else is welcome to it as well.

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I read Emerson on the can. A foolish consistency is the hobgoblin of little minds...true...but a consistent reading of Emerson has its uses nevertheless.

StuMusic

The StewMac calculator is fine and there are several others out there to work as well. I use fret calculator programs when I set the fret positions.

It's nice to know how to calculate the fret positions yourself, however. There are two ways to do it. One whay, which is the way most people do it, is to rely on the fact that the ratio of the scale length to the distance to the first fret is a constant.
25.4/ 1.4256 = 17.817 (17.817 is our magic constant and it works for all fret boards)
Now that you know this constant, you can figure out any fret board.
25.4 / 17.817 = 1.4256 (just checking our results from above.)
Once you've found the position of the first fret, you now have a new scale length that you can use to find the next fret.
25.4 - 1.4256 = 23.974
We can calculate the next fret position from there.
23.974 / 17.817 = 1.3455 (17.817 is the same magic constant!)
Add this fret offset to the previous fret offset and you get the position of this fret relative to the nut.
1.4256+1.3455 = 2.771.

One problem with this approach is that the position of each fret is calculated from the previously calculated fret. An errors that occur because you didn't use enough decimal places will cause your numbers to go wrong.

The second way uses the fundamental formula that is the basis for the 12 note scale. This formula does not rely on a previous calculation and directly calculates the each fret position. That formula is:
fret_position = ( 1 - ( 1 / (2 ^(fret_number / 12)))) * scale_length.

The first fret would be:
fret_position = ( 1 - ( 1 / (2 ^ (1 / 12)))) * 25.4
2 ^ (1 / 12) = 1.059463
1 / 1.059463 = .9438744
1 - .94423 = .056125
Our scale length is 25.4
.056125 * 25.4 = 1.4255
By the way .056125 is our Magic constant in another form:
1 / .056125 = 17.817

You can do this on a calculator that has exponentiation. (y ^ x).