bracing for my 13-fret Nick Lucas L-00

[Mark McLean]

I have been following with interest the construction of Allen's Norman Blake style guitar. My current build (my number 2) will not have those beautiful inlays, the birdseye maple, or the clever adjustable neck (I'll get to that on number 4, or later......) - but it does have a similar issue with forward shifted bracing. I am making a 13-fret model of a L-00 with a deep body, like the Nick Lucas model, being demonstrated here by a certain 60's folk icon.

I would appreciate your considered advice on the bracing that I am planning. You will recall that some poorly planned bracing caused some problems with my last guitar, so I am being pretty cautious this time.

The top is Adirondack, 3.2mm thick at the neck end and down to the bridge area, thinning to 2.5mm around the edge of the lower bout and tailblock. The soundhole is a little undersized (96mm diameter), which is also similar to the NB Martin, and I have installed a simple herringbone rosette and a cocobolo soundhole binding, to match the bindings that will go around the mahogany sides and back.



I am building from a plan for a 14-fret L-00 and I want a 13-fret neck joint. The neck is already built, and the scale length is 24.7 inch. For the body I plan to move the bridge, soundhole and all of the bracing south (towards the tailblock) by a distance equivalent to the distance between the 13th and 14th frets (which is 16.5mm). I figure that if I move the soundhole as well I will avoid any problems associated with opening up the gap between the X-brace and the soundhole, or the bridge. The upper part of the soundboard will be a bit longer, but I plan to beef-up the upper-face brace a bit to compensate for that. The bracing that I am planning is parabolic (not scalloped) and I plan to leave it rectangular and full-height between the X and the front of the bridge, and then to taper to the ends, which will be tucked into the kerfing. Here is how it looks in a preliminary lay-out (brace wood is sitka). Nothing is glued yet, and the X-braces are not carved. I have pre-shaped the smaller braces, but I am not certain that these are the ones that I will end up using. A cardboard template of a possible bridge is in place to show the relationship between the bridge and the braces. The distance between the X and the front of the bridge is about 1.5 inches.



Do you think that I am on the right track?
thanks
Mark

[Allen]

It sure likes you're on the right track to me. Sounds like you've thought it out, and planned well.

I don't see that there will be as much shifting around as on my latest with only one frets difference on yours.

[graham mcdonald]

I have always liked to have the X crossing over the rear corners of the bridge. It just feels structurally right. You could do that by just closing the X a little, which might also help the bass on a small bodied guitar by building a little less cross grain stiffness in the X.

At the same time it will probably work quite well the way it is. It is going to be more the mass and shape of the braces you glue as much as the exact layout.

As someone else sig line says, its only a guitar

cheers

graham

[Bob Connor]

I think you are on the right track mark. It's a pity that Hesh has gone AWOL because he's built an L00 and he's about to start another (with parabolic bracing). I think he'll be back sometime in the next week when he finishes the courses he's doing. A pm might be the go so he has a look when he comes out of hibernation.

I've played the L00 he built form Tiger Myrtle and Lutz spruce and it's a veeeeeery nice instrument.

[Mark McLean]

Thank you gentlemen. I am really starting to understand some of the theory and practice behind this stuff now, compared to the purely cook-book approach that I had a year or so ago when I first started. It has been good to just jump in and have a go, and then learn from the errors.

After a month of rain and humidity we now have RH of 40% in Sydney, predicted to continue for the rest of the week. Happy days! I will get some gluing done, but I'll also PM Hesh before I get too much further.
Mark