Cut plastic by marking the area to be cut with a pencil and making several passes over the mark with a sharp utility knife. Turn the plastic over, and snap the edges together so that it folds. If necessary, trim along the fold with the knife, and sand rough edges.Continue Reading
Measure carefully, and mark the cut using a straight edge and a sharp pencil. For curves, use a French curve or compass to keep the line smooth.
Hold the straight edge along the cut mark. Run a sharp utility knife along the straight edge to score the cut. Repeat three or four times, going a little deeper with each pass. Score curves with the help of a French curve.
Turn the plastic over. Hold the edges on either side of the cut mark, and snap them together to fold or break the plastic along the scored line.
If the plastic did not break all the way through, run a utility knife along the fold to finish the cut.
Rub a sanding block along both cut edges to remove roughness.