You can cut any size circle and even piece together oversize circles out of foam board with precision cutting tools and correct measuring. Precision cutting tools are very sharp, so it's important to handle them with extreme care. Keep these tools out of the reach of children.
Things You'll Need
Sturdy cutting surface
Self-healing cutting mat
Precision cutting tool
Step 1: Prepare Your Work Area
Select a work area with a hard surface. Place a self-healing cutting mat on the work surface to protect your surface. If you don't have a mat, you can use a piece of cardboard. Place the foam board and your tools on the table all within easy reach.
Step 2: Choose a Circle Size and Measuring Method
There are two main methods for preparing to cut a circle out of foam board: template and compass/string.
Template method: Set a piece of cardboard on your work space. Adjust your compass to the size of the circle. Draw your circle on cardboard by placing the compass point into the cardboard and drawing the circle with the pencil end. Cut out the template with a pair of scissors.
Use tin cans, canisters or jar lids to make quick and easy templates.
Compass/string method: Adjust your compass to the size of the circle. Place the point of the compass directly onto the foam board and draw the circle with the pencil end. You can do the same thing without a compass by tying a knot in the end of a piece of string and tacking that end to the center of the board. Tie the other end of the strong around a pencil. Keep the string taut and your finger on the thumbtack. Use the pencil end to draw your circle.
Step 3: Cut Out the Foam Circle
Foam board has two layers: a light cardboard layer and the actual foam layer. For the sake of precision, it's best to make two cuts. The <ahref="https: www.youtube.com="" watch?v="Y4JXjLhJPqI""> </ahref="https:>first cut will go through the cardboard layer and the second cut will go through the foam.
For the template method, set your template on the foam and lightly draw around the shape of it with your pencil. Alternatively, keep the template in place as a barrier, so the knife doesn't slip as you cut. Apply slow, consistent pressure first cutting through the cardboard layer and then cutting through the foam layer. Trim any roughness with a scissors.
If you drew the circle directly on the foam board using the compass/string method, start by applying slow, consistent pressure with your cutting tool, first cutting through the cardboard layer and then cutting through the foam layer. Trim any roughness with a scissors.
For oversize circles, cut out half-circles or quarter-circles from the foam board. Once these pieces are cut, they can be joined together with regular craft glue.