I started by cutting the two 8" discs from the 3/8" plywood stock for the spool sides. Drill six 1/2" holes centered 2-1/4" out from the center of the discs and spaced equally around the discs at 60º intervals. Drill these holes through both discs at the same time to insure that the holed are lined up to accept the 1/2" hardwood former dowels. They must be drilled vertically. I used a drill press. You can use a hand drill if you are careful.
Drill holes through the exact centers of the discs again drilling them at the same time and vertically to insure that they are lined up. These holes will accommodate the metal tubing for the 3/8" carriage bolt spool axle.
Cut six lengths of 1/2" hardwood dowel each 2-1/4" long. These are the spool formers. Insert them into the sides of the discs using a waterproof glue to hold them in place. I left a smidgen of each dowel stick out of both discs so that they could be nice and flush with the surfaces after final sanding.
Epoxy the metal tubing in place that the axle bolt goes through.
Drill a hole through one of the discs between two adjacent dowel former rods to accept the bolt that will hold the 1" wood ball crank knob. Mount the crank knob. Set the spool assembly aside today.
Now would be the logical time to make the additional spools because you have the tools and materials at hand. I was anxious to see how the finished product turned out so I only made one spool.
The next step is the 3/4" plywood handle assembly. Cut it out according to the drawing. You would want to size and contour the hand grip to be comfortable for your hand. Drill the holes for the 3/8" spool axle bolt and the 1/4" spool stop/wrist strap. Drill the holes for the line guide mounting bolts. Round the edges of the plywood handle assembly.
Cut the line guide from the 1/16" aluminum strap. Other materials could be used for the line guide; stainless steel or a strong springy plastic. This "pack rat" had the aluminum strap material in the old goat shed so that is what I used. Be sure that the oval hole on the tip that your line goes through has no rough edges. You don't want to fray and weaken your high dollar braided Dacron flying line.