Lutherie Demystified Ep. 15 | Techniques: Bracing and Brace Carving 

This is a great question which I neglected to address in the video. Refering to the 0:59:31 mark in the video, you want to strive for a similar resonance if your objective is consistency of sound regardless of the material. Depending on your materials, then you want to adjust your flexibility to achieve that resonance. For a solid top, I recommend a resonance on the higher side of the range shown, approximately 165 Hz, because that is typically the range that the solid material wants to land in, but which also makes a very nice sounding guitar. The deflection that achieves this is typically on the stiffer side of the ranges shown, namely 0.090 in. for the with-grain and 0.055 in. for the cross-grain. The reason for the higher stiffness in the solid top is given at the end of Ep. 14. If you start with a stiffer solid top plate as in Ep. 13 (compared to a double top in Ep. 14), the extra stiffness will naturally carry over into the bracing process. Thank you for asking.

@@GarrettLeeLuthier Thank you a lot, Garrett 👍

Thanks for the encouragement, Kris! I will try my best.

That's correct. We'll address the effect of the bridge in Ep. 19.

There are two issues you are addressing. The first is where the domed top meets the sides and lining. In order to get the best fit, the sides with its lining are often "bowl sanded" with sandpaper attached to a radius dish of the same curvature of the braced soundboard. This is a fairly standard technique in modern building where the entire side assembly is made independent of the neck, or at least before the top is attached to the neck. In plantilla systems, the tentalones (or even lining) can be angled to comply to the dome or left at 90 and accept a small kink at the periphery. The second issue arises in the upper bout where the incoming neck is at a positive angle relative to the soundboard's plane (which can be domed or more commonly, left flat). In both cases, the underside of the fingerboard is faceted in the area between the 12th fret and the soundboard to comply with that angle. Finally, if the the lower bout is bowl sanded and the upper bout left flat, most builders sand a small transition zone of decreasing angles in the rim at the region of the waist.

I'm glad you're finding the videos helpful. The neck is adjustable and you can see it here: ru-vid.com/video/%D0%B2%D0%B8%D0%B4%D0%B5%D0%BE-akHdBRnK-qE.html

By the way, this is Michael Fontenot. I messaged you a coule of times directly.

Michael, The Smallman and Sons tops that I have measured were about 1.2 mm thick, but you'll find a range of thicknesses used by makers depending on the nature of the lattice and the materials used, such as balsa vs. spruce or cedar, and whether capped with carbon fiber and epoxy. You'll likely find everything from the Australian-style thickness all the way up to that of a standard solid top. It's hard to generalize, but the one thing you can say is that the assembly must work as a system and in the context of the chasis.

Thanks Gary, That gives me a sense of what to do.

I'm sorry, there are no plans.