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I am building the Antes (2007) 000 auditorium guitar. I have lost the page that give the scale length but when I set my lmi template on the drawing it reads to 25.4
Strangely on the lmi site it says the scale is 24.9. I layed the 24.9 scale out on my template & it still catches the bridge plate. What are the considerations if I want to use 24.9?

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Mike McNerney

Other than placing the bridge correctly to the scale length, make sure that the bridge wings still land on the X brace.

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http://www.Harvestmoonguitars.com

Assuming it is the 14 frets/body version the difference in scale length is what makes one an OM (25.4) and the other a triple O (24.9).
You will only be moving the bridge closer to the soundhole by a quarter inch, which should move the wings further over the X brace, so as long as the bridge pin holes have room to fit between the legs of the X brace and you are not looking for the "forward shifted" sound you should be fine.

I like to adjust the X-brace on any guitar by making sure that the braces hit the lower corner of the bridge. This is mostly for structural reasons. I have the same plans and mostly build OM's and have made a slight change in the angle to sure that up. Of course you will get full strength if the X goes even further on the bridge but I think it closes down the tone a bit. Not necessarily a bad thing but if you like that open airy sound then loosen it up a bit.

Depending on where your fingerboard is ending you may need to shift the soundhole up a little too.

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Jim Watts
http://jameswattsguitars.com

I believe that most of the considerations have been covered, so this is really more about how to approach the problem. On scale changes, I was taught to draw out the change using the edge of a sheet of butcher paper as the centerline of the guitar in planform. After locating the edge of the body and ideal 14th fret location, the distance from that fret to the nut may be determined, and the distance from the 14th fret to the uncompensated saddle determined. Average centerline saddle compensation is added to that distance to give actual nut and actual saddle location on the centerline. For those using additional nut compensation, that may be subtracted from the 'nut to 14th fret' distance. I also added the 20th fret location and my desired distance from that fret to the end of the fretboard.

This layout sketch may then be positioned atop the Antes plan and aligned with the centerline of the planview to visualize the change in bridge position, nut location, and the end of the fretboard. This should allow you to execute the adjustments to the soundhole location, top bracing, and the bridge plate with confidence, as well as to address the slightly shorter neck shaft length layout on the neck blank.

There are a range of other considerations if you are building with cosmetics in the Martin style (e.g., end of fretboard versus inner rosette ring), but that covers things as far as the structural arrangement and location of major components.

I would also suggest you review the previous discussions on this site re: the Antes plans in general and specifically, the plan you are using. Besides the incorrect tuner layout and grossly over-braced construction, there are a number of other quirks which you may wish to address as you replan for the shorter scale length.

And to reiterate what was (figuratively...) beaten into me at Greenridge, all Martin guitars built with a 14 fret 000 body are 000 guitars without regard to scale length, phase of moon when built, etc. UNLESS two additional conditions are met: the longer scale length of 25.34" is used and a 1-3/4" wide nut employed. While Martin occasionally deviated from that practice since they rationalized the meaning of the OM moniker in the late 1950's, those violations appear to be reserved for artist special editions, apparently with the idea that if an artist lending his or her name to a guitar chooses to invoke the marketing magic of the OM tag, the artist gets what he or she wants.

Also note that this OM versus 000 business is a Martin thing... many builders and even other manufacturers vary from the practice for whatever reason, and obviously may refer to their guitars in any way they choose to without anything other than the occasional snicker or a sotto voce raspberry from the Martin fanistas. Further, from 1929 through at least the mid-1950's, Martin used the OM designation - if with some degree of inconsistency - to refer to their 14 fret-to-body models versus 12-fret-to-body six-string guitars, so a maker might always choose to invoke tradition versus 'modern' practice.

Good luck with your project!

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A constellation only takes shape when one maps the whole.
- Beth Brower