Instructables

Make A Cornice Box for Your Window

Step 1: Get The Required Stuff

I went to the Home Depot and had them cut a sheet of 1/8" plywood into 8" strips.  I also got any materials that I didn't have around the house, such as drywall anchors, "L" brackets and extra staples for the staple gun

I then gathered up all the tools and materials I thought I would need.

-Wood
-Batting
-Fabric
-Saw
-Measuring Tape or Yardstick
-Pencil
-Glue
-Clamps
-Staple Gun & Staples
-Small Shelf Brackets (I got the smallest I could find which were about 3-4 inches per "arm"
-Short screws for attaching brackets to the cornice
-Drywall anchors
-Screws appropriate for use with drywall anchors
-Hammer
-Drill
-Screwdriver

Step 2: Measure and Cut

I had the Home Depot cut my sheet of 1/8" plywood into 8" wide strips.  Then I measured the length of the curtain rod the cornice has to cover and added 2 inches for extra clearance.  I figured the cornice would stick out 5" so I had to cut two 5" "flaps" per cornice. 

I made lines where I had to cut, and made my cuts. 

I clamped down a scrap piece of wood to use as a straight edge to help get straight cuts.

Step 3: Glue and Clamp

Picture of Glue and Clamp
After all my pieces are cut, it is time to start gluing.  I glued the 2x2 pieces onto the edges of the long boards.  Once the glue was dry I glued the short piece to form a corner.

This step took a LONG time because I only had 2 clamps.  I waited at least 45 minutes before I removed the clamps so I could glue the next part.  Just take your time and make sure everything is dry before you remove the clamps.