How to Build a Dock Box
- 1). Measure the space where you want your dock box and decide how high it will be.
- 2). Transfer the measurements for the length and width to the marine plywood to form the bottom of the box. Cut this piece out of the plywood with a circular saw. Add 1 inch to the length and width when measuring to make the top. Mark that dimension onto the plywood and cut that piece.
- 3). Cut two pieces of plywood, each 2 inches wide and as long as the width of the top, to serve as the front and back sides of the lid. Cut two more pieces of plywood, 2 inches wide and 1 inch longer than the top, to serve as the ends of the box top. Attach these strips to the outside edge of the box top with finishing nails. This will create a lip around the outside of the top that will fit down over the box and help seal it. Countersink the nails to ensure they can be covered with caulk easily. Caulk all the seams and the nail heads with marine silicone caulk.
- 4). Cut two pieces of plywood, measuring the length of the bottom of the box and the height of the box, to form the front and rear panels. Cut two more pieces of plywood, measuring the height of the box and 1 inch less than the width of the box to form the end panels.
- 5). Nail the front and rear panels to the front and rear edge of the bottom of the box, then nail the side panels to the front, rear and bottom. Countersink the nails. Seal all seams and nail heads with marine silicone caulk.
- 6). Paint the box and the top inside and out with marine epoxy paint. Allow both to dry thoroughly before setting the box onto the dock.
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