This Instructable will show you how to make a concrete umbrella base from an IKEA lamp shade using basic tools and materials. The lamp shade is relatively cheap and makes an attractive concrete mold that can be re-used for dozens of castings. The size of your umbrella will determine the diameter of the pipe that gets cast into the concrete, and also the overall size of the base. For larger umbrellas or gusty spaces, you'll want a larger umbrella base that weighs about 100 pounds. The smaller lamp shade makes a base that weighs about 60 pounds.
There are four steps in this Instructable - Assembling the Form, Casting Concrete, De-molding, and Finishing.
Materials and Supplies:
- IKEA Melodi Lamp Shade or similar plastic container
- 3/4" Plywood (approximately 16" x 16") for Base Board
- 3/4" Plywood for Bracing
- 2" Galvanized Pipe with Floor Flange OR PVC pipe (Actual size is determined by your umbrella pole.)
- 1" x 3/4" Foam Strip 50" long, covered in clear packing tape
- 100% Silicone Caulk
- Modeling Clay
- 2-1/2" Hole Saw and Drill
- Screw Gun
- Pre-Drill and Countersink Bit
- 1-1/4" Drywall Screws
- Hack Saw or Angle Grinder
- Concrete Polisher (optional)