It is important that your Omnigrid® rotary cutter is held at a 90◦ angle when cutting. Holding the cutter even slightly slanted can cut the mat. Always use a sharp blade – dull blades can damage the mat. When a mat is kept on a cutting table, it is easy to continuously cut on the same area of the mat each time. Eventually, this will cause the mat surface to weaken and pieces of the mat may come off, leaving a worn area and even gashes. Occasionally turn your mat or move to another position when cutting.