Assemble the Base
Position the end rails flush with the bottom edge on one side rail and against the ends of the support rail attached to the side rail. Be sure the end rail assembly is positioned so its support rail is at the bottom. Drill 3/8-inch countersunk holes for the 3/8-inch furniture buttons, and attach using glue and 1-5/8-inch screws (Image 1).
Cut the copper pipe per the cut list.
Insert the copper pipe parts through the holes in the support rails attached to the assembly (Image 2). To help ease the pipe through the holes, you can apply liquid soap or paste wax inside the holes.
Position the remaining side rail assembly with its support rail flush against the side rails and the copper pipe inserted in the holes in its support rails. Drill 3/8-inch countersunk holes and attach using glue and 1-5/8-inch screws.