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Several questions on 12 & 13 fret guitars.
1st, do you cut off the 1st or 2nd frets from the nut end?
2nd, is the compensation changed?
3rd, can you use a 14 fret body plan?
4th, how do you locate the bridge , as in 25.4" scale minus 1 or 2 frets?
You get the idea. Basicaly what all needs to change?

Hmm .. dont take this the wrong way, but you need to read a bit somewhere to understand how guitars are built around the scale length and its math...

so ...

1 - nothing gets cut off at the nut .. the whole FB simply gets shifted towards the body.
2 - no, the comp is still the same - all you have done is shifted the neck/body joint.
3 - yes.. I do it all the time - the body size/shape really has nothing to do with where the neck joint goes. Might not look the best with some shapes, but thats YOUR choice.
4 - same way as any other guitar .. measure from the 12th fret, add the comp - neck joint doesnt dictate bridge placement (well OK, it sort of does but..) - the FB and its scale length do.

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Tony Karol
www.karol-guitars.com
"let my passion .. fulfill yours"

You don't "cut off" frets... The neck is just jointed at 12, instead of 14...
If you'r scale is 25,4, your bridge will be at 25,4 from your nut.
Then, if you have the same scale for a 12 and a 14, the bridge on the 12 will be more back.

Francis

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Francis Richer, Montréal
Les Guitares F&M Guitars

to take this discussion a little further , You need to understand scale length 101 . It matters not what fret connection to the body you use , 12-13-14 , it matters not . Todd and the others hinted at the scale length relationship . All you accomplish by cutting off the 1st fret is to shorten the static scale length of that board.
Scale length is the placement of the fret slots in relation to the nut. If you measure from the nut to the 12th fret and double it , you get the static scale length. This isn't the compensated length , to get that you need to add some length to the placement of the saddle so you can accommodating the working length of the string so your intonation will be better.
If you place the saddle at the static scale length you will find the guitar will not intonate well and will sound sharp. You also need to add some compensation angle between the treble E and Bass E. About 1/8 " works well. Martin uses a 3 degree angle and Gibson used 4. The scale length is also important for brace location and as Todd point out the bridge and sound hole . On the Norm Blake where a 14 fret body is used with a 12 fret neck , the scale length makes everything move down the body and the fret board is shortened byt cutting off the end fret , this will shorten the fretboard and not change the scale length.
I hope this helps clear things a bit and I am sure others may add to the discussion.

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John Hall
blues creek guitars
Authorized CF Martin Repair
Co President of ASIA
You Don't know what you don't know until you know it

So basicaly they're for shorter armed people to make lower frets easier to reach?

For short arm people has little to do with it. And it does not make lower ferts more accesable in fact it makes the 13 th and beyond more difficult to access.

It all has to do with building a guitar that has a shorter scale lenght.

There are a couple of reasons that a player may want a short scale instrument.
1. A short scale string length will have less tension when tuned to pitch than the same gauge of string in a longer scale.
2. The distance between frets is slightly less which may make it a bit easier to play certain chords or scales.
The reasons one may want a guitar with 12 or 13 frets to the body join are slightly different.
1 . Moving the nut closer to the body also moves the position of the bridge farther into the body of the guitar. In other words the bridge ends up being almost centered in the lower bout of the guitar, depending on the body style of course. This in turn changes where the top is being driven from, there by making quite a bit of difference in the tone produced. I've found that instruments with 12 or 13 frets clear of the body have substancially different bass response compared to those with 14 frets clear of the same body design. Of course when moving the bridge and soundhole one must also move the bracing accordingly, if you are adapting a long scale 14 fret plan.

I hope this helps explain a few of the reasons that these instruments have been made. I've attached a picture of a guitar that I built for a fellow last year that was patterned after a longscale 14 fret plan and built as a short scale 12 fret guitar. This guitar has a great well defined bass response but still has good trebles because of the smaller body size. He loves sunburst finishes and 1 7/8" necks.

Cal

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Remember, there are no stupid questions, only stupid answers!

So then Cal, a 12 or 13 fret guitar normally has a shorter scale length like say a 24.9? I understand about moving everything back. I asked about scale lengths in another post. I just wasn't sure how a 12 fretter was done. It seemed like you could cut of the the 1st 1 or 2 which would be like capoing but I wasn't sure. I was thinking about a 13 fretter with a cutaway for my next one.

Thanks, John