You can use the Dremel rotary tool to grind glass with special bits designed for use with glass, such as the diamond or silicon carbide grinding stones. Apply water to the glass while grinding for safety. This keeps the glass dust from spraying into your eyes and nose and helps cool and lubricate the glass surface during grinding. Use a slow, steady speed and gentle pressure. Do not try to rush the job or you risk breaking the glass.
Insert the diamond, tungsten carbide or silicon carbide tip into the Dremel rotary tool and tighten the chuck. Make sure it is seated as far into the tool as it can go as this helps reduce vibration.
Set the glass to be ground in a tub or on a towel so water can be applied to the surface while grinding.
Hold or prop the glass at the best angle to grind the edge or surface that needs grinding. Make sure the glass is stable and will not move while you are grinding.
Apply water to the surface of the glass you want to grind and put on the safety glasses. Keep applying water during the grinding process to clean and lubricate the grinding bit. If a paste starts forming, use more water.
Start the Dremel and bring the bit gently into contact with the glass that needs grinding. Make sure to keep water supplied to the grinding process by sprinkling or slightly submerging the glass.
Wash the glass thoroughly when finished to remove all the grit and glass dust generated by the grinding process.
The speed settings recommended by Dremel are 25-35,000 RPM for the diamond wheel points, 18-35,000 RPM for the tungsten carbide cutters, 25-35,000 RPM for the silicon carbide stones and between 12 and 24,000 RPM for the polishing accessories rated for use on glass.