Figuring out bracing locations with different scale lengths

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Phil
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Figuring out bracing locations with different scale lengths

Post by Phil »

So some of you have probably read my thread about some recent mistakes I made (cutting a Les Paul fingerboard too short and trimming L-0 rosewood sides too short) and I am going ahead with using those sides to make a L-0/parlor hybrid. So that the Les Paul fingerboard doesn't go to waste (its already fretted and inlaid) I want to use it on this build. So here's the thing, an L-0 is 24.75" scale length, the LP board is for a 24.625" scale. That makes an 1/8" difference. To compensate, should the bracing be shifted towards the neck by that same 1/8"? What about the braces between the soundhole and neck, should they be shifted as well?

It seems pretty straight forward to me that this is all that would be required, just want to make sure I'm not missing anything. Thanks.
johnnparchem
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Re: Figuring out bracing locations with different scale leng

Post by johnnparchem »

Your reasoning sound good to me but with the slightly shortened scale you may not have to do anything with the braces. You should lay it out on paper with a few considerations. With the shorter scale the bridge will move up an 1/8", that might force you to move the x-brace up a touch to make sure you are not drilling holes into the side of the Xbrace. You might also check how the fretboard will land on the rosette. Most rosettes are open on the top and you want to make sure your fretboard goes past the rosette. If need be move the sound hole up an eighth. Depending what happens with any changes you need to make you might need to move other braces.
tippie53
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Re: Figuring out bracing locations with different scale leng

Post by tippie53 »

when I start planning a guitar the first thing is the fretboard. Once you have that info you can plot everything else. Braces are scale length located. Martin shifted the braces in 1939. I don't think 1/8 in one way or the other will be a structural issue but that little bit can do things to the tops movement and tone.
What is your tone target? If you are looking for that vintage sound you want to use a bit more forward shift to the bracing. More modern you want to go the other way. I have a set bracing pattern than I use and move it according to my scale length . Once you know the nut position and the scale length you now know where the saddle is set to. Here you can plot the bracing off that position.
John Hall
Blues Creek Guitars Inc
Authorized CF Martin Repair Center
president of Association of Stringed Instrument Artisans
http://www.bluescreekguitars.com
songman101
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Re: Figuring out bracing locations with different scale leng

Post by songman101 »

Hello John
Great advice for all newbies :-) .I have been wondering about this very issue on the fingerboard settings in relation to the scale lengths.--- So that I understand it, the frett board should cover the sound hole at the inside edge of the rosette (hole) and the nut is the starting point of the scale length measurement therefore also locating the bridge position?
Thanks stephen
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