How to Cut Glass Lenses

Use a permanent marker or a grease pencil to draw the line you want to follow for your cut.

Cut two squares of leather or felt, each roughly 4 inches square. Wrap one square around one edge of the lens and the other around the lens at the opposite end.

Place the lens in the vise with the material-wrapped edges against the inside walls of the vise. Tighten the vise carefully; close it just enough to hold the lens securely in place.

Fit the oscillating power tool with the diamond burr carving bit or glass drilling bit. Turn on the tool and set it to a medium speed setting; adjust this as you work according to the cutting speed that works for you.

Run the spinning cutting tip lightly over the line you drew on the lens. Move slowly but steadily to create a lightly etched line in the glass. Go over this with the tool a second time in the same manner. Continue running over the line until you've etched enough of a groove to keep the tool from skipping and sliding as you go.

Increase the speed of the tool. Move the cutting tip through the groove more slowly to cut more deeply. Continue to repeat this motion until you've cut through the lens. Remove the lens from the vise to complete the cutting, if necessary.

Clean any remaining markings from the cut lens using fingernail polish remover. Coat the cut edge of the lens with clear nail polish or varnish to make the opaque edge transparent before using in you craft project.