Making the Mold

Mike showed me how to make a mold out of any shape you might like your uke to be. I had a Tenor ukulele plan from Hana Lima Ia’ and had shrunk it down to a Concert size. So, we are going to use that pattern.

1. ¼” thick Plexiglas is cut on the band saw. Allow approximately 2” on each side (just the top and bottom and one long side) of the ukulele shape. The other long side is the center line and goes right up to the center line on your pattern. Joint one edge (this is the center line).

2. Line up the center line edge of Plexiglas sheet to center line of pattern and with a felt tip pen carefully draw half of the outline shape onto Plexiglas. You are only looking at half of the ukulele shape with the Plexiglas.

3. Cut out most of the uke shape with the band saw and then fine tune the line with a belt-sander. Keep checking shape to make sure it is what you want. Be sure to look carefully for any flat spots you might want rounder.

4. Take a sheet of ¾” Baltic Birch plywood and cut four pieces. The width of the wood will be cut as the same width you just cut the Plexiglas with. Joint one long edge of each piece. These 4 pieces of Birch can be jointed together. Again, this will be the center line of the mold. Now, sand edges with the belt-sander.

5. Drill holes into the Plexiglas with a countersink pilot bit. Screw Plexiglas template (with 1 ¼” #8x screws) onto one of the four pieces of plywood. Make sure the top edges are flush. Cut out the excess wood (uke shape) with a band saw and finish up with router to trim the rest of the wood. The Plexiglas template with a bearing on the router will make the exact cut of the pattern into the wood. All four plywood pieces are done this way.

6. Match up two of the wood sides and put into a vice making sure they go together perfectly. You can tap one side with a hammer to get it exact. Be sure to make sure center lines and tail and head block areas are perfectly matched up. These are screwed together with same screws (3-1 ¼” #8x). The other two pieces of wood are done in the same way. We now have two pieces of Baltic Birch that are 1 ½” thick for our mold.

7. Now place the two halves together in a vice. You will cut two scraps of wood approximately 1 ½” x 6” and attached one to the top of the mold and one to the bottom with the same size screws. Voila! You are now finished with the outside where the side of the uke will sit in. We now need to make the inside clamp which will hold the sides to the shape of the mold.

8. Take a turn buckle and hacksaw off the loops on the ends. Get two scraps of wood and trace the curvature of the uke pattern waist on one block. This shape is cut out on the band saw. Trace the line from the previous cut scrap of wood onto the second and cut that out. Find the center of each block and on its flat face drill a hole into each block that will correspond to the screw of the turnbuckle. The screw on one side of the turnbuckle is screwed into the hole of one block and the other side of the turn buckle is screwed into the other block creating the pressure to hold the sides of the ukulele in place in the mold.

9. Mike then took the mold over to the drum sander and ran it through to make it nice and smooth.

10. He then made me an inside template (just a piece of Plexiglas the shape of half an ukulele). He showed me how to mark it by cutting into the template with a saw to mark the center of the soundhole, brace locations, saddle position and the best was how to mark a ¼” all around the template with a router guide with a pencil stuck in it. How clever!