How to Cut an Octagon Window on Mat Boards
- 1
A stop sign is in the shape of an octagon.Thomas Northcut/Stockbyte/Getty Images
Lay the ruler on the back of the mat board. Using the ruler and pencil, draw an octagon. Each of the eight sides needs to measure the same length. For example, make each side two inches. - 2). Hold the hobby knife at a 45 degree angle. Insert the tip of the knife into the mat board, along one of the pencil lines. Cut along the lines, moving slowly.
- 3). Push the cutout octagon from the mat board. Run the hobby knife along the cut edges of the mat board to smooth out any uneven spots.
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