The ultimate coffee table

Step 11 Step 9: Build mold for tray

To build the mold for the tray I took MDF and cut them in increments to build a pyramid shape for the mold. I cut them on the band saw and then stair stepped the pieces. I glued up the pieces to create two halves of the mold (top and bottom).

I made two halves so it would be easier to cut on the band saw. Making this angled cut would be hard and dangerous (making a jig would be another option). Then I drew the profile pattern of the tray on the pieces. I cut out each piece on the bandsaw using this line.

Finally, glue these two pieces together, after set up you want to smooth the piece. Any imperfections will be seen in the plastic tray. I smoothed it with an orbital sander. Apply bondo, and sand smooth following the bondo instructions. Use different colors of bondo to help you see any imperfections or uneven areas. It takes time but is worth it to have a smooth part.

The triangular mold sits on a flat sheet of MDF. Drill small holes every 2 inches or so to allow the vacuum to suck down on the part. A 1/8" drill bit is good, too large of a hole will cause the plastic to create divits as the vacuum will pull it into the hole. The smaller bits allow for suction without imperfections in the plastic.