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Size
Alpha® Wet Core Drill Bit
The Alpha® Wet Core Drill Bit is built for fast, clean drilling of faucet-mounting holes in granite and engineered-stone countertops and vanities, and for rounding the internal corners of square or rectangular sinkholes. Direct-sintered diamond segments are vacuum-brazed to a steel core, with diamonds on the side of the core to prevent undercut during manual drilling. Each bit is 4" in usable length, threaded 5/8"-11 to fit drill presses with a water swivel or wet polishers such as the Alpha® VSP-320, AIR-680 and AWP-158. Available in nine US sizes from 3/8" through 2-1/2". Wet use only — do not exceed 3,500 RPM.
Features
- Designed for faucet-mounting holes in countertops and vanities
- Very fast cutting on granite and engineered stone
- Diamonds on the side of the core prevent undercut during manual drilling
- Direct-sintered diamond segments vacuum-brazed to a steel core for durability
- Cleans up internal corners on square and rectangular sinkholes
- 5/8"-11 thread fits most popular water-fed polishers and drill-press swivels
- Versatile for water, gas and electrical piping work in construction trades
- Wet operation only — maximum 3,500 RPM
| Part No. | Size | Type | Thread | UPC |
|---|---|---|---|---|
| DCB00380 | 3/8" | Wet | 5/8"-11 | 749173460326 |
| DCB00500 | 1/2" | Wet | 5/8"-11 | 749173460333 |
| DCB00750 | 3/4" | Wet | 5/8"-11 | 749173460340 |
| DCB01000 | 1" | Wet | 5/8"-11 | 749173460357 |
| DCB01250 | 1-1/4" | Wet | 5/8"-11 | 749173460364 |
| DCB01375 | 1-3/8" | Wet | 5/8"-11 | 749173460371 |
| DCB01500 | 1-1/2" | Wet | 5/8"-11 | 749173460388 |
| DCB02000 | 2" | Wet | 5/8"-11 | 749173460395 |
| DCB02500 | 2-1/2" | Wet | 5/8"-11 | 749173460401 |
- Mount the bit on a wet polisher (VSP-320, AIR-680, AWP-158) or a drill press equipped with a water swivel. Hand-tighten on the 5/8"-11 spindle.
- Build a drill template from a 3/8" granite tile, scrap engineered-stone, or composite material. Clamp the template to the workpiece with the polished side facing the workpiece for accurate centering.
- Place a scrap stone underneath the work area to support the backside of the slab and prevent blow-out chipping when the bit breaks through.
- Start water flow before the bit touches stone — water must run continuously to cool the diamond segments and flush slurry.
- Begin drilling at a low RPM with light pressure; do not exceed 3,500 RPM at any point.
- Apply steady, even pressure. Let the diamond segments cut — forcing the bit will glaze the diamonds and cause heat damage.
- For sinkhole corner rounding, plunge the bit at each corner mark, then connect the holes with a saw cut.
- After use, flush the bit with clean water and store dry. Inspect segments for wear before re-use.
Maximum drillable thickness equals the 4" usable bit length on a new bit. Never run dry — segments will glaze and cutting will stop.
3/8" — DCB00380
| Part No. | DCB00380 |
| UPC | 749173460326 |
| Diameter | 3/8" |
| Type | Wet (water-fed only) |
| Thread | 5/8"-11 |
| Max RPM | 3,500 |
| For Use On | Granite, engineered stone, porcelain slab, marble, limestone, ceramic tile, concrete, gypsum |
| Packaged Weight | Not published by manufacturer |
| Package Dimensions | Not published by manufacturer |
| Commodity Code | 8207.19.3060 |
| Country of Origin | Japan |
| Data Sheet | Tech Note (PDF) |
1/2" — DCB00500
| Part No. | DCB00500 |
| UPC | 749173460333 |
| Diameter | 1/2" |
| Type | Wet (water-fed only) |
| Thread | 5/8"-11 |
| Max RPM | 3,500 |
| For Use On | Granite, engineered stone, porcelain slab, marble, limestone, ceramic tile, concrete, gypsum |
| Packaged Weight | Not published by manufacturer |
| Package Dimensions | Not published by manufacturer |
| Commodity Code | 8207.19.3060 |
| Country of Origin | Japan |
| Data Sheet | Tech Note (PDF) |
3/4" — DCB00750
| Part No. | DCB00750 |
| UPC | 749173460340 |
| Diameter | 3/4" |
| Type | Wet (water-fed only) |
| Thread | 5/8"-11 |
| Max RPM | 3,500 |
| For Use On | Granite, engineered stone, porcelain slab, marble, limestone, ceramic tile, concrete, gypsum |
| Packaged Weight | 0.50 lb |
| Package Dimensions | 6.25" x 1.5" x 1.5" |
| Commodity Code | 8207.19.3060 |
| Country of Origin | Japan |
| Data Sheet | Tech Note (PDF) |
1" — DCB01000
| Part No. | DCB01000 |
| UPC | 749173460357 |
| Diameter | 1" |
| Type | Wet (water-fed only) |
| Thread | 5/8"-11 |
| Max RPM | 3,500 |
| For Use On | Granite, engineered stone, porcelain slab, marble, limestone, ceramic tile, concrete, gypsum |
| Packaged Weight | 0.50 lb |
| Package Dimensions | 6.25" x 1.5" x 1.5" |
| Commodity Code | 8207.19.3060 |
| Country of Origin | Japan |
| Data Sheet | Tech Note (PDF) |
1-1/4" — DCB01250
| Part No. | DCB01250 |
| UPC | 749173460364 |
| Diameter | 1-1/4" |
| Type | Wet (water-fed only) |
| Thread | 5/8"-11 |
| Max RPM | 3,500 |
| For Use On | Granite, engineered stone, porcelain slab, marble, limestone, ceramic tile, concrete, gypsum |
| Packaged Weight | 0.60 lb |
| Package Dimensions | 6.25" x 1.5" x 1.5" |
| Commodity Code | 8207.19.3060 |
| Country of Origin | Japan |
| Data Sheet | Tech Note (PDF) |
1-3/8" — DCB01375
| Part No. | DCB01375 |
| UPC | 749173460371 |
| Diameter | 1-3/8" |
| Type | Wet (water-fed only) |
| Thread | 5/8"-11 |
| Max RPM | 3,500 |
| For Use On | Granite, engineered stone, porcelain slab, marble, limestone, ceramic tile, concrete, gypsum |
| Packaged Weight | 0.60 lb |
| Package Dimensions | 6.25" x 1.75" x 1.75" |
| Commodity Code | 8207.19.3060 |
| Country of Origin | Japan |
| Data Sheet | Tech Note (PDF) |
1-1/2" — DCB01500
| Part No. | DCB01500 |
| UPC | 749173460388 |
| Diameter | 1-1/2" |
| Type | Wet (water-fed only) |
| Thread | 5/8"-11 |
| Max RPM | 3,500 |
| For Use On | Granite, engineered stone, porcelain slab, marble, limestone, ceramic tile, concrete, gypsum |
| Packaged Weight | 0.70 lb |
| Package Dimensions | 6.25" x 1.75" x 1.75" |
| Commodity Code | 8207.19.3060 |
| Country of Origin | Japan |
| Data Sheet | Tech Note (PDF) |
2" — DCB02000
| Part No. | DCB02000 |
| UPC | 749173460395 |
| Diameter | 2" |
| Type | Wet (water-fed only) |
| Thread | 5/8"-11 |
| Max RPM | 3,500 |
| For Use On | Granite, engineered stone, porcelain slab, marble, limestone, ceramic tile, concrete, gypsum |
| Packaged Weight | 1.00 lb |
| Package Dimensions | 6.5" x 2.25" x 2.25" |
| Commodity Code | 8207.19.3060 |
| Country of Origin | Japan |
| Data Sheet | Tech Note (PDF) |
2-1/2" — DCB02500
| Part No. | DCB02500 |
| UPC | 749173460401 |
| Diameter | 2-1/2" |
| Type | Wet (water-fed only) |
| Thread | 5/8"-11 |
| Max RPM | 3,500 |
| For Use On | Granite, engineered stone, porcelain slab, marble, limestone, ceramic tile, concrete, gypsum |
| Packaged Weight | 1.30 lb |
| Package Dimensions | 6.75" x 2.75" x 2.75" |
| Commodity Code | 8207.19.3060 |
| Country of Origin | Japan |
| Data Sheet | Tech Note (PDF) |
| Property | Detail |
|---|---|
| Brand | Alpha Professional Tools® |
| Operation | Wet only (water-fed) |
| Maximum RPM | 3,500 |
| Thread / Arbor | 5/8"-11 |
| Usable Length | 4" maximum drillable depth |
| Segment Construction | Direct-sintered diamond segments vacuum-brazed to steel core |
| Side Protection | Diamonds on side of core to prevent undercut |
| Compatible Materials | Granite, engineered stone, porcelain slab, marble, limestone, ceramic tile, concrete, gypsum |
| Recommended Tools | Alpha® VSP-320, AIR-680, AWP-158, or drill press with water swivel |
| Available Sizes | 3/8" · 1/2" · 3/4" · 1" · 1-1/4" · 1-3/8" · 1-1/2" · 2" · 2-1/2" |
| Commodity Code | 8207.19.3060 |
| Country of Origin | Japan |
- VSP-320 — Variable Speed Electric Wet Polisher with central water feed (recommended host tool)
- AIR-680 / AIR-658 — Pneumatic Wet Stone Polishers with water feed
- AWP-158 — Wet Air Polisher
- Laser Core Bits — Wet/Dry Laser-Welded Segmented Core Bits for heavier-duty work
- CNC Core Bits for Porcelain & Sintered Slabs — for Dekton®, Neolith® and crystallized glass
- PSC-150 — Pneumatic Stone Cutter for sinkhole cut-outs
- Eased Edge / Tile Bullnose Kit — on-site finish-edge creation
Q: Why are there diamonds on the side of the core?
When you drill a hole manually, unstable conditions can cause undercut. Side diamonds, applied via vacuum-brazing technology, protect the steel core and improve drilling stability and ease.
Q: How long do Alpha® Wet Core Bits last?
Life expectancy varies with bit size and material. In testing, 1-1/4" and 1-3/8" bits achieved over 350 core drill holes through 1-1/4" (3 cm) granite slabs.
Q: What materials can I core-drill with this bit?
Granite, engineered stone, porcelain slab, marble, limestone, ceramic tile, concrete and gypsum.
Q: Can I run this bit dry?
No. Water is required to keep the diamond segments cool. Without water the segments will glaze and cutting ability will stop.
Q: What RPM should I run?
Do not exceed 3,500 RPM under any circumstances.
Q: Can I use this on an electric or pneumatic polisher?
Yes — it is highly recommended on the Alpha® VSP-320 and AIR-680, which have central water-feed systems.
Q: Can I use this on a high-speed angle grinder with an outside water feed?
No. Alpha® only recommends wet core bits on polishers with central water-feed systems. High-speed angle grinders lack central water feed.
Q: What is the thread size?
5/8"-11.
Q: What kind of template should I use?
Use 3/8" granite tile, a scrap of engineered stone, granite slab or composite material. Templates are built by the operator and should be clamped with the polished side facing the workpiece for accuracy.
Q: Can I use this on a drill press with a water swivel?
Yes — but use caution. The extra length of the swivel attachment can damage the bit under excessive feed pressure.
Q: What is the maximum stone thickness I can drill?
The usable length of a new bit is 4", which is the maximum drillable thickness.
⚠ WARNING: This product can expose you to chemicals including Cobalt, which is known to the State of California to cause cancer. For more information go to www.P65Warnings.ca.gov. Always wear appropriate PPE.
Especificaciones
| Size | 1", 1-1/2", 1-1/4", 1-3/8", 1/2", 2", 2-1/2", 3/4", 3/8" |

























