Lay your 4-by-8 foot, 3/4-inch birch plywood sheet on a flat working surface. Use your tape measure and pencil to mark the plywood sheet to the dimensions you require. To determine how large your wooden slab desktop should be, use your tape measure to record the length and width of your desk frame. Add 2 inches to each side of the desk frame to calculate your target desktop size. For example, if your desk frame measures 36 by 60 inches, your desktop should measure about 40 by 64 inches.
Use a C-clamp to fasten a straight 1-by-4 inch board to the top of your plywood sheet, for use as a guide when cutting your desktop length. Position the board parallel to your pencil marks, so that when placed against it, your circular saw blade touches the pencil marks dead on. Clamp the board down firmly and use your circular saw to make the cut. Repeat the same process to cut the desktop width.
Use your miter box and hand saw to cut a 45-degree angle at one end of a piece of 1-inch square wood edging. Place the edging against one of the long sides of your plywood desktop, so that the shorter end of the mitered edge lines up with the desktop, and the longer edge projects outward and past the corner.
Mark the other end of the 1-inch trim, where the opposite end of the desktop falls. Use your miter box and hand saw to cut a 45-degree angle at this end as well, using your pencil mark as the shorter end of the angle. Repeat this process to create edging for each side of the desktop.
Apply wood glue to the inner edge of your desktop trim. Use clamps to hold the trim in position along the edge of the desktop. Allow the wood glue to dry according to the manufacturer's instructions.
Use your portable router and 3/8-inch rounding bit to create a rounded edge along the top of your edging. Hold the router in position against the side of the edging, and run it down the length of the desktop. Repeat the same process on all sides, until the edging is uniformly rounded.
Use your 220-grit sandpaper to smooth the entire surface of the desktop, and edging.
Mount L-brackets to the desk frame. Lay the desktop onto your desk frame L-brackets. Use your power drill to make pilot holes along the underside of the desktop, using the screw holes in your L-brackets as a guide. Use your screwdriver and 3/4-inch wood screws to fasten the desktop in position.
Use your paint brush to apply two coats of polyurethane to your desktop. This sealer will prevent stains and damage from liquids and normal use. Apply the polyurethane, and allow it to dry according to the manufacturer's instructions.
Things You Will Need
- 4-by-8 foot 3/4-inch thick birch plywood sheet
- Tape measure
- 1-by-4 inch board
- Circular saw
- Miter box
- Hand saw
- 1-inch square wood trim
- Wood glue
- 3/8-inch rounding bit
- 220-grit sandpaper
- Power drill
- 3/4-inch wood screws
- Paint brush
- Consider using an old hollow core door as a low-cost wood slab desktop building material. If you do not mind allowing the size of your old door to dictate the size of your new desktop, a hollow core door can easily be transformed into a perfectly functional desktop. Just place the door onto a sturdy framework, and screw small wooden shims onto the underside of the door to hold it in position on the frame.