Laser-Welded Diamond Core Bits for Hard Surfaces Alpha® Laser Diamond Core Bits are aggressive core drill bits for drilling porcelain and sintered slabs, granite, quartz, engineered stone, marble, and other hard building materials. Their laser-welded construction supports demanding countertop fabrication, installation, and construction drilling applications. Coring Bits for Countertops and Sink Cutouts The core bits create faucet-mounting holes in countertops and vanities and rounded corners for square or rectangular sink cutouts. Available diameters from 3/8" through 4" also accommodate openings for water, gas, and electrical piping in compatible materials. 5/8"-11 Core Drill Bits for High-Speed Grinders Each diamond core drill bit has a 5/8"-11 thread for use with compatible high-speed angle grinders. A compatible core bit extension also allows the coring bits to be used with appropriate hammer drills and rotary hammers. Wet and Dry Diamond Core Drilling Bits The 3/4" through 4" sizes support wet or dry drilling, while the 3/8" and 1/2" core bits are wet-use-only. Sizes through 2" have a maximum operating speed of 12,000 RPM, while the 2-1/2", 3", and 4" models are rated for a maximum of 8,400 RPM.
