Acornhouseworkshop

The bracing for the back is much simpler than the soundboard bracing. The back won’t be facing the stresses of the strings’ tension, and, acoustically, it is not in direct contact with the strings’ vibrations. (although it still needs to be somewhat resonant) A center seam of cross grain spruce is glued to reinforce the joint of the two halves. Then cross bracing, slightly arced towards the tips, is glued perpendicular to the center seam. A very simple scalloping at the ends finishes the backbracing.

Before gluing the back kerfing, however, the sides need to be sloped. While the top of an acoustic guitar is (mostly) flat, the back tapers halfway, so that the headblock is shorter than the tailblock. A good paring chisel and block plane are essential here. Then, after getting as close as you dare with them, you break out the sanding board, a long flat board of plywood with sandpaper attached, to evenly flatten both sides according to the newly added slope.

Now we’re ready to add the back kerfing, and then attach the back. Then, the basic construction of the body is complete. All that’s left is the binding, finish sanding and smoothing, making the bridge, and adding the finish, glueing the bridge, and doing the final setup of the nut and saddle. Still much to do, but the end is in sight; way over there in the distance, but in sight – especially if you squint!

This entry was posted on September 16, 2009 at 2:54 pm and is filed under Acorn House. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.