Construction begins with 1/36-inch birch veneer coated with approximately 20 percent polyvinyl formal by weight after the solvent has been driven off. The veneer is pressed into panels at elevated temperature to a specific gravity of 0.95, then cooled in the press. Two corners are trimmed from the future root end before further sideways compression raises that end's specific gravity to 1.3. The resulting board has a high-density, double-compressed root, a transition zone, and a medium-density blade and tip. After rough patterning, several boards are assembled into a blank with cold-setting glue. The blank is then carved in the same way as the Douglas fir blade.
Notable Point · 0:45-1:38
Compressing birch veneer into a dense propeller root
Treated birch veneer is pressed and then compressed sideways at the root, producing a dense root joined to a lighter blade and tip.