摘要 |
A device and method for cutting and grinding a hard but brittle material (such as glass plate, etc.) for producing a doughnut-shaped substrate are provided. The device of the present invention comprises a tubular core rod and shank extending therefrom and coaxial therewith. A plate is attached to the rod and shank and extends therefrom. A skirt is attached to the plate and surrounds the rod. Both the rod and skirt include at least one circumferential cavity. A core drill and a skirt drill are integral with the core rod and skirt, respectively. The cavities, skirt, and drills include diamond whetstone parts. |