Workshop: Rebracing a '40s Kay Jumbo



Step 1: remove the binding, remove the back. The second part of that is made slightly-miserable by the ply mahogany wanting to explode on its seams...


Step 2: wonder at the aftermarket maple bridge plate cap, aftermarket truss rod, and bridge-pin-hole-drill-buffer masking tape still clinging to the bottom.


Step 3: kill the old braces, sand the surface.


Step 4: cut and install "Bohmann double-x-style" bracing. I call these brace "blanks" because this is not the finished product.


...as you can see, that 150+ year-old spruce is looking mighty fine for this application. That grain is nice and tight and on the quarter.


Step 5: begin shaping the braces by tapering the ends.


Step 6: almost finish the carve of the braces by getting them rectangular in shape and really thin at the ends.


Step 6: scallop and "triangular-ize" the braces as you see fit. Lightly sand-off. Don't care too much about how they look -- concentrate on how the top sounds when you tap it -- you might be in there through the soundhole to cut them further, anyhow.

Step 7: admire the retro oddity of a spruce bridge plate with a thin, 1/32" piece of birch plywood protecting the pin-hole area. That's actually a very strong little sandwich and wears well.

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