Having the old blade to use as a pattern is a big help. The flat or pitch side of the blade ends are in the same plane. Here you can see the leading edge of the blade. The airfoil side is to the right. The drop or pitch will be cut into the blade on the left side.
I needed a pattern to mark out the drop and decided to make one out of a piece of thin metal strip material I had. This was fastened to the trailing edge of the old blade.
I then traced the drop distance onto the metal and cut this material off making the pattern I could trace onto the new blade blank.
With the metal pattern attached to a blade blank's trailing edge I could trace the drop onto that edge. I marked the edge with X's that defined the area to be removed. Removing this amount of material from the trailing edge up to the leading edge would give me a pitch of about 7-8 degrees near the root and diminishing to zero degrees at the tip.
Made another metal pattern for the airfoil design at the blade tip.
Clamped the first blade blank to my bench and went to work with my trusty jack plane. On the trailing edge of the blade you can see the layout lines. The top line is the drop giving the pitch to the blade. The line below the drop line sets a thickness of 3/16" for the trailing edge. The two red lines on the surface of the blade on the top right define the area where the leading edge will be rounded.
The drop material has been removed down to the line. The blue line and X's on the bottom marks the material that will be removed at the trailing edge on the airfoil side of the blade. This all makes more sense after you have read Dan's book a few times and made a blade or two out of styrofoam. First cut has been made. Now I will do the same to blades two and three. Then begin work on the airfoil sides.
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