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Just a quick question to make sure I'm not missing something. I got a crap no-name neck intending to use it in a mockup design of a guitar body, just to cut out the body in pine blanks and see how it balances with a neck attached. The neck was supposed be a Strat, i.e. have a 25 1/2" scale length. But check out these pix I've uploaded, where I'm measuring from the front edge of the nut to the tang of the 12th fret. The unstrung neck is as straight as I could get it using a notched straightedge, totally flat on the left side and just a tiny hair of forward bow on the right, so a bit of twist but too small to register with the naked eye (mine, anyway).

Anyway, as the photos show, the measurement here at the 12th fret is almost exactly 13"--it's right in the middle between 15/16 and 13", i.e. it's 15/16 and a half (31/32) which would give me a scale length of 25 15/16". So if I were to actually make a guitar with this neck, just as a first-time experiment knowing that it won't be very good and using all cheap/crap parts cannibalized from junk guitars so it won't cost much, I would need to put the bridge saddles at about 26 1/16, right? (I've read that you need to give an eighth extra so the saddles have some wiggle room for intonation).

Or am I trying to be too precise here?

For all practical purposes, you scan ignore the second pic. It's just there to prove that my (extremely accurate) graduated straightedge was butt-flush with the nut when I took the photo (and yes, the physical butt of the ruler is its mark zero). The important image is the one at the top, clearly showing that the middle of the fret, i.e. the tang, is exactly in the middle of 12 15/16 and 13.

There is NO #13 "clearly showing" in your pictures - only a #12.

If that fret is the 12th fret at 12 inches you have a 24" scale neck - like a Fender Mustang, Jaguar, etc.

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"Act your age, not your shoe size" - Prince

Must be a baritone neck.

Measure the heel and compare it to the Fender standard(s). You should be able to tell where the body joint is located. If it is a conversion neck it will be slightly beyond the 16th fret. If its right at the 16th fret then you will have to move the bridge.

Baritone conversion necks are usually 27 or 28 inch scale (Warmoth makes one). I did a 26.5 scale on a 12 string that was intended for lower tuning (but not a bari). I would be very careful using that neck for any prototyping if you plan to switch to something else.

Face palm! THAT was a well-deserved smackdown. In my defense, I have dyscalculia, the mathematical equivalent of dyslexia. It makes my brain do funny things with numbers. Still, I should've caught something that obvious. Apologies to the others who answered.

But the fraction part of the question remains valid. The fraction still looks like a 31/32 which would give me a scale length of 23 15/16" rather than a straight-up 24". So, assuming that what I've read is correct and I should allow another eighth (because of string deformation upon fretting which causes the string to go sharp if the bridge is precisely at scale), I should put the saddles at 24 1/16. Correct?

The second picture shows the 11th fret near the 12 inch mark not the 12th fret. . .

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

I beg to differ. The second photo shows that 12" falls near the 11th fret. Please say that you do know which fret is the 12th fret. (Edit: Bryan and I were typing at the same time and I see that he caught that mistake too.)

But here is the answer to your question. Adjust the high e saddle on your bridge to about the half way point of its range. Place that saddle at a point 0.15" further back from the theoretical scale length (23-15/16" or 25-15/16"). That should be a good starting point for the bridge.

Barry's answer to the question asked is good. However, I'm betting that, in this case, the measurement from the nut to the 12th fret will actually be 12 3/4' making the scale teh expected 25.5".

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

Barry: thanks for the correction. As a player, I never thought of a fret in terms of the wire. When you're looking at it strictly from a player's point of view, a "fret" is, in practical terms, the place where one's finger presses down on the string. As a result, I've always thought of "fret" as the in-between space, NOT the little metal bars. So fast-forward to the present: I looked at the proper in-between space and assumed that the first of the two bars defining that nth space would be the nth fret. But that, of course, would mean that the nut counts as a fret. Your comment prompted me to actually count the wire bars, not the spaces. Imagine that. Seems obvious, in retrospect, but when you've been playing for ca. 40 years (albeit with large hiatuses) and you've been thinking the same way that whole time, that perspective is so deeply ingrained that it takes a jolt like yours to make one realize that something's off with one's thinking.

Bryan: you won that bet; you are absolutely correct.

In sum: the problem wasn't a funky neck but my own funky mind. Nonetheless, a problem there certainly was, and this forum is saving me from making some time-consuming and stupid mistakes. Better to do some stupid thinking beforehand and get it all sorted out before any drilling, cutting, or routing. Thanks to everyone here for your generosity and patience as I stumble around. Very much appreciated.

We are glad to be of service.

_________________
"Act your age, not your shoe size" - Prince

I’m glad it worked out! Good luck moving forward on your project!

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

Happy you figured it out. I had a sneaking suspicion that you were looking at the gaps instead of the actual frets. One term to know about is the "speaking length" of a string. That is the part of the guitar string that is free to vibrate extending from the inside face of the nut or the mid point of the fret, down to the saddle. This is a key concept which comes into play often during guitar work.

I can see how it can be counter intuitive. In fact as a guitar teacher that's one of the things I try and hammer home with my beginning students, "what exactly we're talking about when we talk about frets." It's an important distinction, not simply because when you're playing "Smoke on the water" it goes 0 3 5, 0 3 6 5, etc. and you have to know how to find specific numbered frets (if we're not speaking in specific note terms), but from a technique perspective thinking of the 3rd fret as the actual fret wire (the place where the string terminates thus shortening the speaking length of the string) and not the whole space will encourage a student to snug the finger up as close as possible to the fret, which in turn will better serve the player when it comes to playing notes cleanly and in tune.