Diamond Core Bits for Dry Countertop Drilling Alpha® Dry Diamond Core Bits provide aggressive, high-speed drilling in granite, quartzite, engineered stone, porcelain, and crystallized glass. Designed for dry use, these core bits eliminate the water and slurry associated with wet drilling, simplifying countertop fabrication and installation work. Faucet Holes, Sink Cutouts and Utility Openings The bits create openings for countertop and vanity faucets, water lines, gas lines, and electrical routing. They can also form clean, rounded corners when preparing square or rectangular sink cutouts. Core Drill Bits for High-Speed Grinders Each size has a 5/8"-11 thread for compatible high-speed angle grinders and requires an operating speed between 6,000 and 12,000 RPM. Available diameters range from 1/2" through 2", while new bits provide a maximum drilling depth of 4". Dry or Wet Drilling Guidance Although developed for dry drilling, these diamond core drill bits can also be used wet, and Alpha recommends wet operation whenever practical. They should not be used on marble or with low-speed wet polishers that cannot meet the 6,000 RPM minimum operating speed.
