Common Specifications and Models of Electric Hammer Drill Bits: A Comprehensive Guide

Electric hammer drills are indispensable tools in construction, renovation, and industrial applications, designed to penetrate hard materials like concrete, masonry, and stone through a combination of rotational force and rapid hammering action. The drill bits used in these tools are engineered to withstand extreme stress and deliver precise, efficient results. This guide explores the common specifications, materials, and models of electric hammer drill bits, highlighting leading brands and their flagship products.

1. Key Specifications of Electric Hammer Drill Bits

1.1 Shank Type

The shank is the part of the drill bit that connects to the hammer drill’s chuck. The two most prevalent shank types are:

• SDS-Plus (Slotted Drive System-Plus): A standard for medium-duty applications, SDS-Plus bits feature a 10mm shank with four grooves (two open and two closed) for secure locking and high torque transfer. They are compatible with most rotary hammers and combination drills.
• SDS-Max: Designed for heavy-duty tasks, SDS-Max bits have a 18mm shank with five grooves (three open and two closed), enabling them to handle larger diameters and higher impact forces. They are commonly used in industrial-grade rotary hammers.
• Spline Shank: An older standard, spline-shank bits have a 12mm shank with multiple ridges for grip. While less common today, they are still found in some legacy tools.

1.2 Material Composition

Drill bits are typically made from high-speed steel (HSS) or carbide-tipped alloys:

• HSS Bits: Suitable for lighter applications, HSS bits are cost-effective but wear faster under heavy use.
• Carbide-Tipped Bits: These feature a tungsten carbide tip bonded to an HSS or steel body, offering superior durability and heat resistance. Carbide bits are ideal for drilling into reinforced concrete, granite, and other abrasive materials.

1.3 Diameter and Length

• Diameter: Ranges from 4mm to 65mm, with common sizes including 6mm, 8mm, 10mm, 12mm, 16mm, 20mm, and 25mm. Larger diameters (e.g., 40mm–65mm) are used for anchor holes and structural installations.
• Length: Varies from 100mm to 1,000mm, depending on the application. Longer bits are used for deep drilling or through-hole applications.

1.4 Flute Design

The flutes are the spiral grooves on the bit that remove debris from the hole. Common designs include:

• Single Flute: Efficient for fast chip removal in soft materials.
• Double Flute: Balances speed and stability, suitable for general-purpose use.
• Multi-Flute: Found in premium bits, these reduce vibration and improve heat dissipation during prolonged drilling.

1.5 Tip Geometry

• Cross-Cut Tip: Features a four-facet design for clean penetration and reduced bit walking.
• Centering Tip: A pointed tip that helps maintain accuracy during startup.
• Spear-Shaped Tip: Optimized for masonry, this design minimizes slippage and enhances chip removal.

2. Leading Brands and Their Flagship Models

2.1 Bosch

Bosch is a pioneer in SDS technology, with a reputation for precision and durability.

• Bosch SDS-Plus Blue Granite Hammer Drill Bits:
  • Specifications: Carbide-tipped, 4-flute design, diameters from 4mm to 25mm.
  • Features: The Blue Granite coating reduces friction and heat buildup, extending bit life by up to 5x compared to standard bits. Ideal for drilling into reinforced concrete and brick.
  • Models: GBH2-28DF (25mm diameter, 450mm length) for heavy-duty anchoring.
• Bosch SDS-Max Carbide Hammer Drill Bits:
  • Specifications: 18mm shank, diameters up to 65mm, lengths up to 1,000mm.
  • Features: Designed for industrial rotary hammers, these bits feature a reinforced core for maximum impact resistance. The centric tip ensures accurate starts in hard materials.
  • Models: GBH12-52DV (65mm diameter, 800mm length) for large-scale demolition and drilling.

2.2 Hilti

Hilti is synonymous with professional-grade construction tools, known for innovation and reliability.

• Hilti TE-CX SDS-Plus Hammer Drill Bits:
  • Specifications: Carbide-tipped, 4-flute design, diameters from 6mm to 25mm.
  • Features: The TE-CX series uses a patented carbide blend for enhanced wear resistance. The optimized flute geometry ensures efficient debris removal, reducing downtime.
  • Models: TE-CX 20×400 (20mm diameter, 400mm length) for drilling into dense concrete.
• Hilti TE-YX SDS-Max Hammer Drill Bits:
  • Specifications: 18mm shank, diameters up to 50mm, lengths up to 1,000mm.
  • Features: Built for high-performance rotary hammers, these bits feature a solid carbide head for extreme durability. The centric tip and multi-flute design minimize vibration and improve accuracy.
  • Models: TE-YX 40×800 (40mm diameter, 800mm length) for core drilling and structural anchoring.

2.3 DeWalt

DeWalt offers a wide range of hammer drill bits tailored to both professionals and DIY enthusiasts.

• DeWalt DT6043 SDS-Plus Hammer Drill Bits:
  • Specifications: Carbide-tipped, 2-flute design, diameters from 6mm to 25mm.
  • Features: The DT6043 series is engineered for general-purpose drilling in concrete and masonry. The rock carbide tip enhances durability, while the precision-ground flutes improve chip removal.
  • Models: DT6043-QZ 16×160 (16mm diameter, 160mm length) for light to medium-duty tasks.
• DeWalt DT6048 SDS-Max Hammer Drill Bits:
  • Specifications: 18mm shank, diameters up to 40mm, lengths up to 600mm.
  • Features: Designed for heavy-duty applications, these bits feature a reinforced core and a 4-cutter head for faster drilling. The optimized flute design reduces heat buildup, extending bit life.
  • Models: DT6048-QZ 32×600 (32mm diameter, 600mm length) for large-diameter holes in reinforced concrete.

2.4 Makita

Makita is renowned for its high-performance power tools and accessories.

• Makita B-49373 SDS-Plus Hammer Drill Bits:
  • Specifications: Carbide-tipped, 4-flute design, diameters from 6mm to 25mm.
  • Features: The B-49373 series uses a premium carbide grade for superior wear resistance. The centric tip ensures accurate starts, while the multi-flute design improves debris removal.
  • Models: B-49373 18×450 (18mm diameter, 450mm length) for medium-duty drilling in concrete.
• Makita B-67629 SDS-Max Hammer Drill Bits:
  • Specifications: 18mm shank, diameters up to 50mm, lengths up to 1,000mm.
  • Features: Built for industrial use, these bits feature a solid carbide head and a reinforced core for maximum impact resistance. The optimized flute geometry reduces vibration and improves drilling speed.
  • Models: B-67629 40×800 (40mm diameter, 800mm length) for heavy-duty demolition and drilling.

2.5 Milwaukee

Milwaukee is a leader in cordless and corded power tools, with a focus on durability and innovation.

• Milwaukee 48-20-5030 SDS-Plus Hammer Drill Bits:
  • Specifications: Carbide-tipped, 4-flute design, diameters from 6mm to 25mm.
  • Features: The 48-20-5030 series features a reinforced flute design for improved chip removal and a centric tip for accurate starts. The carbide tip is engineered for maximum durability in abrasive materials.
  • Models: 48-20-5030 20×400 (20mm diameter, 400mm length) for medium-duty drilling in concrete and brick.
• Milwaukee 48-20-5180 SDS-Max Hammer Drill Bits:
  • Specifications: 18mm shank, diameters up to 50mm, lengths up to 1,000mm.
  • Features: Designed for high-performance rotary hammers, these bits feature a solid carbide head and a multi-flute design for efficient debris removal. The optimized geometry reduces vibration and improves drilling speed.
  • Models: 48-20-5180 40×800 (40mm diameter, 800mm length) for heavy-duty applications like core drilling and structural anchoring.

3. Specialized Models for Niche Applications

3.1 Long-Reach Drill Bits

For drilling through thick walls or floors, long-reach bits (e.g., 800mm–1,000mm) are essential. These are commonly used in:

• Utility installations: Drilling holes for pipes or cables through concrete walls.
• Structural engineering: Creating anchor holes in deep foundations.
• Demolition: Breaking through reinforced concrete slabs.

3.2 Tile and Glass Drill Bits

While not strictly hammer drill bits, some models are designed for drilling into fragile materials like tile or glass without cracking them. These feature:

• Diamond-tipped or carbide-coated heads for precision.
• Reduced hammering action to prevent damage.
• Examples: Bosch DT6033 Tile Drill Bits (6mm–12mm diameters).

3.3 Core Drill Bits

For creating large-diameter holes (e.g., 50mm–150mm), core drill bits are used with specialized core drilling machines. These feature:

• A hollow cylindrical design that removes a core of material rather than pulverizing it.
• Diamond-tipped or carbide-coated edges for cutting through concrete and stone.
• Examples: Hilti TE-YX Core Drill Bits (50mm–150mm diameters).

4. Factors to Consider When Choosing Electric Hammer Drill Bits

4.1 Material Hardness

• For soft materials like brick or light concrete, HSS bits may suffice.
• For reinforced concrete or granite, carbide-tipped bits are mandatory.

4.2 Drill Bit Diameter

• Smaller diameters (e.g., 6mm–12mm) are suitable for anchors and fasteners.
• Larger diameters (e.g., 20mm–65mm) are used for structural installations and demolition.

4.3 Drill Bit Length

• Short bits (e.g., 100mm–200mm) are ideal for surface drilling.
• Long bits (e.g., 400mm–1,000mm) are necessary for deep or through-hole applications.

4.4 Shank Type Compatibility

• Ensure the bit’s shank (SDS-Plus, SDS-Max, or spline) matches your hammer drill’s chuck.

4.5 Brand Reputation

• Opt for reputable brands like Bosch, Hilti, DeWalt, Makita, and Milwaukee for guaranteed quality and durability.

5. Maintenance and Care Tips

• Cooling: Allow the bit to cool down after prolonged use to prevent heat-induced damage.
• Lubrication: Apply a light coat of oil to the shank to reduce friction and prevent rust.
• Storage: Keep bits in a dry, organized case to avoid damage and ensure easy access.
• Inspection: Regularly check for wear or damage, especially the carbide tip and flutes.

6. Conclusion

Electric hammer drill bits are critical components that determine the efficiency and success of drilling tasks in hard materials. By understanding the key specifications—such as shank type, material composition, diameter, and length—and selecting bits from reputable brands like Bosch, Hilti, DeWalt, Makita, and Milwaukee, users can ensure optimal performance and longevity. Whether for light-duty repairs or heavy-duty construction, the right drill bit can make all the difference in achieving precise, efficient, and safe results.