You will also be bending over the top of each wall to hide the sharp edge. Draw a parallel line a short distance down from each of the edges. Mark out equal squares on each corner of the rectangle. This square may already be present because of the bending lines that you drew earlier. This square will be cut out to create flaps that become the sides of the box.
If you don’t have a bending brake, lay the sheet on the edge of a table and place a piece of wood on top. Clamp the wood to the table as tight as possible. The piece of wood will act as the brace of the bending brake, allowing you to bend the metal by hand or with a mallet.
Measure the height of the box. Cut four strips of metal, each long enough to reach from the bottom to the top of the box, and wide enough to be bent in half and secured (usually about an inch or so on each side, so 2-3 inches total width). [5] X Research source Insert each strip lengthwise into the bending brake, with half in and half out. Bend each strip lengthwise at 90°
Once all the rivets are set, the box is complete.
Use a miter box to create exact angles. This will make for seamless joints. Make sure that when you cut the 45° angle that you do not affect the overall length of the wall pieces.
