How to Build Window Seat Bookshelves
- 1). Align two 3/4-by-18-by-48-inch plywood boards next to each other. Have an assistant help hold them up on their long, thin sides. Place them parallel to each other about a foot and a half apart, as they will be the top and bottom boards of the bookcase.
- 2). Set a 3/4-by-18-by-18-inch plywood board against one end of the top and bottom boards, so that it lines up with their outside edges. Have the assistant hold the three boards together while you drill into this new board, which is a side board, and make holes every six inches through the side board and into both the top and bottom board. Screw 2-inch wood screws into the holes. Repeat to attach another side board on the other end of the top and bottom boards.
- 3). Set a 3/4-by-18-by-49 1/2-inch plywood board evenly across the frame. Drill holes every 8 inches into this board, which is the rear board of the bookshelf, and into each of the side boards and the top and rear board. Screw 2-inch wood screws into each of the holes.
- 4). Flip the bookcase over and position three evenly spaced 3/4-by-17-by-18-inch plywood boards within the bookcase, parallel to the side boards. Drill two holes through the top and bottom boards into each of these boards, which are the vertical support boards. Screw 2-inch wood screws into each of the holes to fasten the vertical support boards firmly in place.
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