Foam balls can be used in crafts, school projects and home decor. Children play with them without fear of being hurt. Adults can use them as stress relievers. They are lightweight and convenient to carry. They are sold in stores, but to save money and to get a custom size, you can make them easily with a few tools.
Making a Foam Ball
Measure and mark a cube in the block of foam. The cube width will be the diameter of the ball. The cube length, width and height should be the same, so measure carefully.
Cut along the markings on the foam. Because foam is so easily squeezed and moved, don't push on it too hard with your hands or the knife. The sharper the knife, the easier it is to cut the foam. Keep the edges as straight as possible.
Carve the corners. Don't cut too much off at once, or the ball will be lopsided. As you cut the corners, the edges will become smoother and the cube will slowly form into a sphere.
Take the roughly spherical ball and knife and clean up the edges. Don't pull off chunks of foam. This will make holes in the ball.
Remember that the knife needs to be very sharp, so when cutting, be careful not to cut your fingers.