- 1). Measure how far in each direction that you want the corner shelf to extend. Put marks on each wall where the shelf will end. For example, measure 12 inches along each wall.
- 2). Measure the distance between the two marks for the distance of the front of the shelf.
- 3). Cut a pair of 1-by-12-inch boards the distance that you measured in Step 2. Cut four, 1-inch slices off the end of a scrap board; these will be your wall mounts.
- 4). Place a board flat on a work surface. Measure and mark the halfway point on the back edge of the board.
- 5). Position the interior angle of the metal right angle at the halfway point mark, and the interior edge of each leg of the right angle at the front edge of the board that will become your shelf. The midpoint of the back of the board and the two corners on the front edge of the board form the points of a right triangle.
Draw a line along the inside edge of the legs to create the cut line for your corner shelf. - 6). Cut the 1-by-12-inch board along the cut line you drew.
- 7). Position one of the wall mounts--the 1-inch slices that you cut off the end of the scrap board--horizontally on the wall near the corner. Level the wall mount and nail it into place. Repeat on the adjoining wall, ensuring that the two wall mounts are level with each other.
- 8). Place the board you cut on top of the wall mounts. For extra security, insert a nail at an angle through the back of the shelf and into the wall.
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