Shelves are great for storing books, collectibles or whatever. The more shelves you have in your home, the more storage space you have. Stacking shelves are nice because they can be stacked as one tall shelf or separated into separate shelving units. You can make your own stacking bookshelves for less than the cost of buying them already made.
Find the center of two pine boards by measuring with a tape measure. Draw a line across the 12-inch width of the board at the center point using a marking pencil and a straight edge. Cut each board in half using a circular saw. You will have four pieces--each of them will be 3 feet long by 12 inches wide. These are your sides. Cut the three remaining pine boards into 2-foot pieces. You will need to measure and mark eight pieces to be this length. These pieces are the tops, bottoms and shelves.
Prepare the cordless drill by inserting a 1/16-inch drill bit. Lay the side pieces so that the 3-foot length is vertical and the 12-inch width is horizontal. Find the top of the board. The thickness is 1 inch. Measure in 1 inch, horizontally, in the center of the 1-inch thickness. Mark the spots, and drill holes on the marks. The depth of each hole should be about 3/4 inch. The holes will go into the 1-inch-thick by-12-inch-wide end of the board. Measure and mark in 1 inch from each edge horizontally every 12 inches down the length of each board and mark. Drill holes on all marks. Do this to all four boards.
Use two of the pine boards that are 2 feet long and 12 inches wide to create the tops of the shelves. Lay the boards on your work surface so that the length is vertical and the width is horizontal. Measure and mark 1 inch in from each edge horizontally, 1/2 inch in vertically, at the tops and bottoms of the boards. Make 3/4-inch-deep holes on all marks. Use two more of the 2-foot-long boards to make the bottoms. Drill the holes down through the 1-inch thickness as the 12-inch width of the board lays flat on your work surface. Place the holes 1 inch in from each end of the 12-inch width. Holes should be 1/2 inch in lengthwise.
Use the last four pieces of pine board to make the shelves by measuring, marking and drilling 3/4-inch-deep holes in the center of the 1-inch thickness of each end of each board, 1 inch in from each edge of the 12-inch width.
Take all of the boards to the room where the stacking shelves will be placed. Lay them out according to where tops, bottoms, sides and shelves go for each unit. Prepare your cordless drill with a bit that fits the wood screws you will use. Insert the screws into the holes down through the tops into the sides, up through the bottoms and into the sides, and through the sides into the shelves.
Stand the units up. Use finishing nails and a hammer to attach a piece of 1/4-inch plywood to each shelf. This is the backing and is placed against the wall. Move the shelves into position against the wall either stacked or separate.