The Definition of Diamond Glass Cutters

A glass cutter is a tool used to make a shallow score in one surface of a piece of glass that is to be broken in two pieces. The scoring makes a split in the surface of the glass which encourages the glass to break along the score. Regular, annealed glass can be broken apart this way but not tempered glass, since it shatters rather than breaking cleanly into two pieces.

A glass cutter may use a diamond to create the split or more commonly a small cutting wheel is used made of hardened steel or tungsten carbide 4-6 mm in diameter, with its cutting edge ground to a V-shaped profile. Some glass cutters hold a small amount of cutting oil, which both lubricates the wheel and prevents the split in the glass from closing. When properly lubricated a steel wheel can give a long period of satisfactory service. However, tungsten carbide wheels have a significantly longer life than steel wheels and offer other advantages in use, such as greater and more reproducible penetration in cutting and consequently easier parting of the glass.