Puzzles, toys and other projects sometimes require cutting specific shapes. Creating geometric figures in the middle of a wood sheet such as plywood or MDF have three requirements: orientating the shape, laying out out the shape and cutting out the shape while leaving the surrounding sheet intact. A square has four sides and it is easiest to make them parallel to the sides of the sheet of wood, but virtually any orientation is possible.
Orientation and Layout
Mark the location of the square's center on the wood sheet with a pencil. Place the framing square with the short leg flush with the sheet's edge and the long leg against the mark. Draw a pencil line through the mark to establish a reference line.
Determine the orientation of the square. On a square with sides parallel to the sheet sides, a line drawn through two opposite corners runs at a 45-degree angle to the reference line. You can rotate the square up to 45 degrees in either direction.
Place the protractor with the zero point on the center of the square and the straight edge parallel to the reference line. Mark the direction of two corners from the center of the square. For example: If the sides are parallel to the sheet sides, the marks are at 45 and 135 degrees. On a square rotated 45 degrees, the marks are at 90 and 180 degrees and the corners will point at the sides of the sheet.
Find the distance from the center point to each corner. Divide the length of one side of the square by 2, and then by 0.707107, which is the cosine of 45 degrees. For example: If the side of the square is 3 inches, the distance to the corner is 3 divided by 2 divided by 0.70710. 3 / 2 = 1.5 1.5 / 0.707107 = 2.1213
Place the square on the sheet of wood with one leg aligned with one corner angle mark and the center point. Draw a line through the corner angle mark, through the center point and across the reference line. The line extends the distance to the corner on each side of the reference line. Measure along the line just drawn in both directions from the center point. Make a mark at the distance to the corner on each side of the reference line to mark the two opposite corners. Repeat this step with the other corner angle mark for the other two corners.
Align the square with two adjacent corner marks and draw a line through them. Add additional lines for the other three sides.
Cut the Square
Place the drill with the point of the bit at one inside corner of the square. The edges of the drill bit should touch the sides of the square, but not go past it. Drill a hole through the sheet.
Install the cutting bit on the multipurpose tool or the blade on the jigsaw. Insert the bit or blade into the hole. Hold the tool firmly and turn it on. Follow the pencil lines that outline the square from corner to corner to cut out the shape.
File the corners of the cutout to make the corners square if so desired. The round bit on the multipurpose tool leaves a small radius instead of a square cut at corners. Sand the edges of the cutout smooth to remove sharp or rough edges.
Tips & Warnings
- If you use a jigsaw to cut out the square, drill a hole in each corner to make turning the corners easy.
- Wear safety glasses and a dust mask while cutting with power tools. Follow all tool manufacturer safety instructions.
Things You'll Need:
- Tape measure
- Framing square
- Drill with 1/4-inch bit
- Handheld multipurpose tool or jigsaw
- Cutting bit or jigsaw blade
- Wood file
- Sanding tool or block
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