Spherical Reflectors
Step 1: Spray the Styrofoam black.
Step 2: Glue ornaments into holes in the Styrofoam.
Step 3: Make a frame out of four pieces of 1/8”x2’x4” plywood.
Step 4: Glue and nail frame to Styrofoam. Be sure to predrill holes for nails. Use 7 nails on long sides (18”) and 6 nails on short sides (12”).
Step 5: Attach a 1”x1”x4’ stake to Styrofoam box with 2 nails and glue.
Step 6: Insert stake with box into a bucket of sand to hold it strait up.
Taken from Exploratorium Cookbook I Recipe No. 19.