Questions: J-45 Body

by Joe Veillette

Originally published in American Lutherie #102, 2010



David Brooks from Tucson, Arizona asks:

I want to build a 12-string guitar based on a J-45 body or similar. What changes to the 6-string version of the J-45 do I need to make to handle the additional tension?


Joe Veillette from Woodstock, New York responds:

In my experience there are two ways to go. If your idea of a 12-string is what most people are used to (25"–25 5/8" scale), I feel that all you have to do is add about 10% to the cross-sectional dimensions of what you’d use for normal 6-string top bracing. The top thickness as well as the back and sides can remain unchanged. This “normal” 12-string should be tuned down a step to D (many old Guilds came that way), or strung with extra-light strings due to the high tension of the octave strings which otherwise tend to be harder to play, more finicky in terms of intonation, and can often deform the top. Of course this isn’t always the case, but it’s close. In my opinion, both detuning and the use of really light strings are unfortunate compromises. But some people prefer the lower tuning and there’s nothing wrong with it if that’s what you like.