Alpha® Dry Core Bits for Granite, Engineered Stone & PorcelainAlpha® Dry Core Bits are designed for job-site drilling of faucet, soap-dispenser and air-gap holes in granite, engineered stone, porcelain and crystallized-glass countertops — without water. They thread directly onto a high-speed angle grinder with a 5/8"-11 spindle and use Vacuum Brazed diamond on the side of the barrel with undercut protection, giving aggressive cutting action and stable, clean-walled holes. The 4"-long barrel sets the maximum stone thickness a new bit can drill through.Features Designed for jobsite drilling of faucet-mounting holes in countertops and vanities Very fast cutting on granite, quartzite and engineered stone Convenient dry application — no water, no slurry, minimal cleanup High-quality, aggressive Vacuum Brazed diamond construction Makes clean, rounded corners for square or rectangular sinkholes Versatile for water, gas and electrical piping pass-throughs Fits most popular high-speed grinders with a 5/8"-11 spindle Undercut protection on the side keeps drilling stable and easier .dst-accordion { margin-top: 25px; border: 1px solid #FDDCC5; border-radius: 6px; overflow: hidden; } .dst-accordion-item { border-bottom: 1px solid #FDDCC5; } .dst-accordion-item:last-child { border-bottom: none; } .dst-accordion-toggle { display: none; } .dst-accordion-label { display: flex; justify-content: space-between; align-items: center; padding: 14px 20px; cursor: pointer; font-size: 17px; font-weight: 700; color: #231F20; background: #fff; transition: background 0.2s; } .dst-accordion-label:hover { background: #FFF3EB; } .dst-accordion-label::after { content: '+'; font-size: 22px; font-weight: 700; color: #F15C22; transition: transform 0.3s; } .dst-accordion-toggle:checked + .dst-accordion-label { background: #FFF3EB; } .dst-accordion-toggle:checked + .dst-accordion-label::after { content: '\2212'; } .dst-accordion-content { max-height: 0; overflow: hidden; transition: max-height 0.4s ease; padding: 0 20px; background: #fff; } .dst-accordion-toggle:checked ~ .dst-accordion-content { max-height: 5000px; padding: 15px 20px 20px; } Models / Part Numbers Part No. Diameter Thread Max RPM UPC DRB00500 1/2" 5/8"-11 12,000 RPM 749173461330 DRB00750 3/4" 5/8"-11 12,000 RPM 749173461347 DRB01000 1" 5/8"-11 12,000 RPM 749173460715 DRB01250 † 1-1/4" 5/8"-11 12,000 RPM 749173460722 DRB01375 1-3/8" 5/8"-11 12,000 RPM 749173460739 DRB01500 1-1/2" 5/8"-11 12,000 RPM 749173460746 DRB02000 2" 5/8"-11 12,000 RPM 749173461354 How to Use Select the Dry Core Bit diameter that matches your hole spec (1/2" through 2"). Thread the bit fully onto a 5/8"-11 high-speed angle grinder spindle. Clamp a granite, engineered-stone or composite template on top of the workpiece, polished side toward the workpiece, to guide the bit. Start at a tilt to bite a crescent, then bring the bit upright once the kerf is established. Run between 6,000 and 12,000 RPM — never exceed 12,000 RPM and never run below 6,000 RPM. Use light, steady pressure; let the diamond do the cutting. Pause periodically to clear dust and cool the bit. Dry use is intended, but wet cutting is recommended whenever water is available — it extends bit life and reduces dust. Maximum drillable thickness equals the 4" barrel length when the bit is new. Specifications by Variant 1-1/4" — Dry Core Bit — DRB01250 Part No. DRB01250 UPC 749173460722 Size 1-1/4" Type Dry Core Bit Thread 5/8"-11 Max RPM 12,000 RPM Recommended For Granite, Engineered Stone, Porcelain, Crystallized Glass Packaged Weight 0.70 lbs Package Dimensions 6.25" x 1.75" x 1.75" Commodity Code 8207.19.3060 Country of Origin Japan 1-3/8" — Dry Core Bit — DRB01375 Part No. DRB01375 UPC 749173460739 Size 1-3/8" Type Dry Core Bit Thread 5/8"-11 Max RPM 12,000 RPM Recommended For Granite, Engineered Stone, Porcelain, Crystallized Glass Packaged Weight 0.70 lbs Package Dimensions 6.25" x 1.75" x 1.75" Commodity Code 8207.19.3060 Country of Origin Japan Common Specifications Property Detail Application Dry (wet use also permitted) Drive 5/8"-11 Female Thread Maximum RPM 12,000 RPM Minimum RPM 6,000 RPM Barrel Length 4" (maximum drilling depth when new) Diamond Technology Vacuum Brazed with sintered segment and undercut protection Materials Granite, Engineered Stone, Porcelain, Crystallized Glass Not Recommended For Marble (too soft — dry-drill heat may crack the slab) Country of Origin Japan Related & Companion Products Alpha® Wet Core Bits Alpha® Diamond Drill Bits Collection Alpha® Angle Grinders & Polishers FAQs What materials can be core-drilled with Alpha® Dry Core Bits?They are designed for granite, engineered stone and porcelain slab materials, and also work on crystallized glass.Can I use the Dry Core Bits on marble?No. Marble is too soft; the heat generated by dry drilling can crack the material.Can the Dry Core Bits be used wet?Yes. They are designed for dry use, but wet cutting is recommended whenever possible to extend bit life and control dust.What is the maximum RPM for these bits?Do not exceed 12,000 RPM.What is the minimum recommended RPM?Do not run below 6,000 RPM. Slow speeds cause polishing instead of cutting and shorten bit life.Can I use these on a wet polisher?No. Wet polishers run at roughly 2,000–4,000 RPM — too slow for Dry Core Bits. Use a high-speed angle grinder.What kind of template should I use?A template made from granite, engineered stone or composite. Secure it with clamps, polished side facing the workpiece, to guide the bit and prevent walking.What stone thickness can these bits drill through?Up to 4" when the bit is new — the barrel length is the limiting factor.Why are there diamonds on the side of the core?The side diamonds combined with the sintered segment and undercut protection make the drilling action easier, more stable and less prone to binding.What sizes are available?Six standard sizes ship from the factory: 1/2", 3/4", 1", 1-3/8", 1-1/2" and 2". A 1-1/4" option (DRB01250) is also stocked at DST. Videos Angle Grinder with Dry Core Bit How to Cut Internal Corners Angle Grinder with Dry Core Bit on Granite How to Work on Porcelain Paver Tiles Documentation 📄 Dry Core Bits — Helpful Hints 📄 Dry Core Bits — How To Use 📄 Dry Core Bits Flyer 📄 Porcelain Paver Tiles Flyer 📄 Hardscape Blade Chart 📄 Safety Data Sheet — Diamond Core Boring Bit ⚠ WARNING: Cancer and Reproductive Harm — www.P65Warnings.ca.gov. Always wear appropriate PPE.
