What are the models of triangular twist drill bits?

Introduction to Triangular Twist Drill Bits
Triangular twist drill bits, a specialized category within the broader family of drilling tools, are designed to address specific challenges in material penetration, accuracy, and durability. Unlike traditional cylindrical twist drills, these bits often feature a triangular shank or a triangular cutting edge geometry, which enhances grip in drill chucks, reduces slippage, and improves torque transmission. This design makes them particularly valuable in applications where precision and stability are paramount, such as metalworking, woodworking, construction, and automotive repair. The triangular shape, whether in the shank or the cutting zone, also contributes to better heat dissipation, as the increased surface area allows for more efficient transfer of heat away from the cutting edge, thereby extending the tool’s lifespan.

Over the years, leading tool manufacturers have developed a wide range of triangular twist drill bit models, each tailored to specific materials (e.g., steel, aluminum, wood, concrete) and drilling conditions (e.g., high-speed drilling, deep-hole drilling, or precision machining). These models vary in terms of size, coating, flute design, helix angle, and shank type, ensuring that there is a suitable option for nearly every drilling task. In this comprehensive overview, we will explore the key models from top brands, delving into their technical specifications, unique features, and ideal applications to provide a detailed understanding of their capabilities.

Bosch Triangular Twist Drill Bits
Bosch, a globally renowned leader in power tools and accessories, offers a diverse lineup of triangular twist drill bits engineered for performance and reliability. The brand’s commitment to innovation is evident in its use of advanced materials and precision manufacturing techniques, which result in bits that deliver consistent results even in demanding environments.

One of Bosch’s standout models is the Bosch Professional 2608585277 Triangular Shank Twist Drill Bit Set. This set includes 10 bits ranging in size from 3mm to 10mm, each featuring a triangular shank that ensures a secure fit in both keyless and keyed drill chucks. The triangular shank design eliminates the need for a chuck key in many cases, as the shape prevents slippage during high-torque drilling, a common issue with cylindrical shanks. The bits are constructed from high-speed steel (HSS), a material known for its hardness and resistance to wear, making them suitable for drilling into mild steel, cast iron, aluminum, and plastic. The flutes are designed with a parabolic shape, which enhances chip evacuation—critical for preventing clogging and reducing friction during drilling. This design also helps to maintain a cool cutting edge, even during prolonged use. Additionally, the bits feature a 135-degree split point tip, which self-centers quickly, reducing walking (the tendency of the drill to wander off the intended starting point) and ensuring precise hole placement.

Another notable model from Bosch is the Bosch Impact Control Triangular Twist Drill Bit (Model 2608595035). Specifically designed for use with impact drills, this bit is built to withstand the high impact forces generated by such tools. The triangular shank is reinforced with a hardened steel core, providing exceptional durability and resistance to bending or breaking under heavy loads. The cutting edge is coated with Bosch’s proprietary TiN (Titanium Nitride) coating, which increases surface hardness, reduces friction, and improves chip flow. This coating also enhances wear resistance, allowing the bit to maintain its sharpness for longer periods when drilling into tough materials like stainless steel or high-carbon steel. The bit’s helix angle is optimized for impact drilling, with a 30-degree spiral that balances chip evacuation and torque transmission, making it ideal for applications in construction and metal fabrication where speed and power are essential.

Bosch also caters to woodworking professionals with the Bosch WoodMax Triangular Twist Drill Bit (Model 2608585342). This model features a triangular shank for secure chucking and a specialized cutting edge designed for wood and composite materials. The bit is made from high-carbon steel (HCS), which is more flexible than HSS, reducing the risk of breakage when drilling through knots or hard grains in wood. The flutes are wider and deeper than those on metal-drilling bits, allowing for efficient removal of wood chips and preventing jamming. The tip is ground to a 118-degree angle, which is ideal for wood, as it cuts cleanly without splintering the material. Available in sizes from 4mm to 12mm, this bit is a favorite among carpenters and furniture makers for its precision and ease of use.

DeWalt Triangular Twist Drill Bits
DeWalt, a brand synonymous with ruggedness and performance in the power tool industry, offers a range of triangular twist drill bits designed to meet the needs of professionals and DIY enthusiasts alike. Known for their durability and long-lasting sharpness, DeWalt bits are often the first choice for heavy-duty applications.

The DeWalt DW1354 Triangular Shank Twist Drill Bit Set is a popular option for general-purpose drilling. This set includes 14 bits, sizes 1/16-inch to 1/2-inch, all featuring a triangular shank that provides a secure grip in drill chucks, minimizing slippage during high-torque operations. The bits are constructed from M2 high-speed steel, a premium grade of HSS that offers superior hardness and wear resistance compared to standard HSS. This makes them suitable for drilling into a variety of materials, including steel, iron, copper, aluminum, and plastic. The flutes are designed with a 30-degree helix angle, which promotes efficient chip evacuation, reducing heat buildup and extending the life of the bit. The tip is a 135-degree split point, which ensures fast, accurate starting and reduces the need for pre-drilling or center punching. Additionally, the bits are coated with a black oxide finish, which provides corrosion resistance and helps to reduce friction, further enhancing their performance.

For more demanding metalworking applications, DeWalt offers the DeWalt DWA1240 Titanium-Coated Triangular Twist Drill Bit. This model is designed for drilling into stainless steel, alloy steel, and other high-strength metals, where heat and wear are major concerns. The bit features a titanium coating that increases surface hardness by up to 30% compared to uncoated bits, significantly reducing wear and extending tool life. The triangular shank is reinforced with a hex core, adding strength and preventing distortion under heavy torque. The flute design is optimized for deep-hole drilling, with a parabolic shape that ensures chips are efficiently cleared from the hole, even when drilling to depths greater than three times the bit diameter. The 135-degree split point tip is self-centering and stays sharp longer, making this bit ideal for precision machining tasks in automotive and aerospace industries. Available in sizes from 3mm to 12mm, the DWA1240 is a workhorse for professionals who demand consistent performance in tough materials.

DeWalt also offers the DeWalt Max Life Triangular Twist Drill Bit (Model DW1587) for users seeking maximum durability. This bit is constructed from cobalt steel, an alloy that contains 5-8% cobalt, which enhances heat resistance and allows the bit to maintain its hardness at higher temperatures than standard HSS. This makes it perfect for drilling into high-temperature alloys, cast iron, and hardened steel. The triangular shank ensures a secure fit, while the flute design features a variable helix angle—steeper near the tip for fast chip removal and shallower toward the shank for increased stability during deep drilling. The tip is precision-ground to a 135-degree angle, with specially sharpened cutting edges that reduce cutting forces and improve accuracy. The Max Life coating, a proprietary blend of titanium and aluminum nitride, provides additional wear resistance and reduces friction, making this bit one of the longest-lasting options in DeWalt’s lineup.

Makita Triangular Twist Drill Bits
Makita, a Japanese manufacturer known for its precision engineering and high-quality tools, produces a range of triangular twist drill bits that combine innovative design with exceptional performance. These bits are designed to work seamlessly with Makita’s power tools, but they are also compatible with most other drill brands, making them a versatile choice for professionals.

The Makita B-65399 Triangular Shank Twist Drill Bit Set is a comprehensive set designed for general-purpose drilling in metal, wood, and plastic. The set includes 12 bits, ranging in size from 2mm to 10mm, each with a triangular shank that ensures a tight grip in drill chucks, even during high-speed drilling. The bits are made from high-speed steel (HSS-E), which contains added elements like vanadium and molybdenum to enhance toughness and wear resistance. This material allows the bits to withstand the rigors of daily use in workshops and job sites. The flutes are designed with a 25-degree helix angle, which is ideal for a balance of chip evacuation and torque transmission, making them suitable for both low and high-speed drilling applications. The tip is a 135-degree split point, which self-centers quickly and reduces walking, ensuring precise hole placement. The bits are also treated with a steam oxide finish, which provides corrosion resistance and a smooth surface for reduced friction.

For specialized metalworking, the Makita D-46724 Titanium-Coated Triangular Twist Drill Bit is an excellent choice. This bit features a titanium coating that increases hardness and reduces wear, making it suitable for drilling into stainless steel, carbon steel, and aluminum. The triangular shank is designed to fit securely in keyless chucks, eliminating slippage and ensuring efficient power transfer. The flute design is optimized for high-speed drilling, with a parabolic shape that allows for rapid chip removal, preventing clogging and reducing heat buildup. The tip is precision-ground to a 135-degree angle, with sharp cutting edges that minimize cutting forces and improve accuracy. Available in sizes from 3mm to 13mm, this bit is a favorite among metalworkers for its consistent performance and long lifespan.

Makita also offers the Makita B-65592 Triangular Shank Masonry Drill Bit for drilling into concrete, brick, and stone. While not a traditional twist drill, this bit features a triangular shank for secure chucking and a carbide-tipped cutting edge designed to withstand the abrasiveness of masonry materials. The flute design is optimized for removing concrete dust, with wide, deep flutes that prevent clogging and allow for fast drilling. The tip is shaped to penetrate hard materials quickly, reducing the need for excessive pressure and minimizing operator fatigue. This model is available in sizes from 5mm to 16mm, making it suitable for a range of construction and renovation projects.

Irwin Tools Triangular Twist Drill Bits
Irwin Tools, a brand with a long history of innovation in cutting tools, offers a range of triangular twist drill bits known for their precision and durability. The brand’s focus on user-centric design ensures that its bits are easy to use while delivering exceptional results.

The Irwin 3018002 Triangular Shank Twist Drill Bit Set is a popular choice for both professionals and DIY users. This set includes 10 bits, sizes 1/16-inch to 1/4-inch, with a triangular shank that provides a secure fit in drill chucks, reducing slippage and improving control. The bits are made from high-speed steel, which is heat-treated to enhance hardness and wear resistance, making them suitable for drilling into steel, iron, aluminum, and plastic. The flutes are designed with a 30-degree helix angle, which promotes efficient chip evacuation, ensuring that debris is cleared from the hole quickly to reduce heat and friction. The tip features a 135-degree split point, which self-centers and starts drilling immediately, eliminating the need for center punching and reducing the risk of errors. The bits are also coated with a black oxide finish, which provides corrosion resistance and helps to keep the cutting edges sharp longer.

For heavy-duty metal drilling, the Irwin Industrial Tools 3023006 Cobalt Triangular Twist Drill Bit is a standout model. This bit is constructed from M42 cobalt steel, which contains 8% cobalt, making it highly resistant to heat and wear—ideal for drilling into stainless steel, high-carbon steel, and other tough alloys. The triangular shank is reinforced to handle high torque, preventing bending or breaking during demanding operations. The flute design features a variable helix angle, with a steeper angle near the tip for fast chip removal and a shallower angle toward the shank for stability, making it suitable for deep-hole drilling. The tip is precision-ground to a 135-degree angle, with specially sharpened cutting edges that reduce cutting forces and improve accuracy. The bit is also coated with a titanium nitride (TiN) layer, which further enhances wear resistance and reduces friction, extending its lifespan even in high-heat applications. Available in sizes from 1/8-inch to 1/2-inch, this model is a top choice for industrial metalworking.

Irwin also caters to woodworkers with the Irwin 1877755 Triangular Shank Wood Drill Bit. This bit features a triangular shank for secure chucking and a specialized cutting edge designed for clean, precise drilling in wood, plywood, and composite materials. The bit is made from high-carbon steel, which is flexible enough to resist breakage when drilling through knots or hard grains. The flutes are wider and deeper than those on metal bits, allowing for efficient removal of wood chips and preventing clogging. The tip is ground to a 118-degree angle, which cuts cleanly without splintering, making it ideal for finish work in furniture making and carpentry. The bit is available in sizes from 3mm to 12mm, with a smooth finish that reduces friction and ensures smooth drilling.

Milwaukee Tool Triangular Twist Drill Bits
Milwaukee Tool, a brand known for its rugged, professional-grade tools, offers a range of triangular twist drill bits designed for maximum performance in harsh working conditions. These bits are built to withstand heavy use and deliver consistent results in demanding applications.

The Milwaukee 48-89-2330 Triangular Shank Twist Drill Bit Set is a comprehensive set designed for general-purpose drilling in metal, wood, and plastic. The set includes 29 bits, ranging in size from 1/16-inch to 1/2-inch, each featuring a triangular shank that provides a secure grip in drill chucks, minimizing slippage during high-torque operations. The bits are constructed from premium high-speed steel, which is heat-treated to enhance hardness and wear resistance, ensuring long life even with frequent use. The flutes are designed with a 30-degree helix angle, which promotes efficient chip evacuation, reducing heat buildup and extending the life of the bit. The tip is a 135-degree split point, which self-centers quickly and reduces walking, ensuring precise hole placement. Additionally, the bits are coated with a black oxide finish, which provides corrosion resistance and helps to reduce friction, further enhancing their performance.

For specialized applications in stainless steel and other hard metals, Milwaukee offers the Milwaukee 48-89-2340 Titanium-Coated Triangular Twist Drill Bit. This bit features a titanium coating that increases surface hardness, reduces wear, and improves chip flow, making it ideal for drilling into tough materials. The triangular shank is reinforced with a hardened core, providing exceptional strength and resistance to bending under heavy loads. The flute design is optimized for high-speed drilling, with a parabolic shape that ensures chips are efficiently cleared from the hole, even during deep drilling. The 135-degree split point tip is precision-ground to stay sharp longer, reducing the need for frequent sharpening and ensuring consistent performance. Available in sizes from 3mm to 12mm, this bit is a favorite among metal fabricators and mechanics for its durability and precision.

Milwaukee also offers the Milwaukee 48-89-2800 Red Helix Triangular Twist Drill Bit, a premium model designed for maximum speed and efficiency. The Red Helix flute design is engineered to remove chips faster than standard flutes, reducing heat and friction and allowing for higher drilling speeds. The bit is made from cobalt steel, which provides superior heat resistance, making it suitable for drilling into high-temperature alloys and hardened steel. The triangular shank ensures a secure fit, while the 135-degree split point tip self-centers and starts quickly, minimizing errors. The bit is coated with a titanium aluminum nitride (TiAlN) coating, which offers excellent wear resistance and reduces friction, making it one of the most durable options in Milwaukee’s lineup. Available in sizes from 1/8-inch to 1/2-inch, the Red Helix bit is designed for professionals who need to maximize productivity without sacrificing quality.

Dormer Pramet Triangular Twist Drill Bits
Dormer Pramet, a global leader in cutting tools for metalworking, offers a range of high-precision triangular twist drill bits designed for industrial applications. The brand’s focus on advanced materials and engineering ensures that its bits deliver exceptional performance in even the most challenging machining tasks.

The Dormer Pramet A117 Triangular Shank Twist Drill Bit is a versatile model designed for general-purpose drilling in carbon steel, alloy steel, and cast iron. The bit features a triangular shank that provides a secure grip in drill chucks, ensuring efficient torque transmission and reducing slippage. It is made from high-speed steel (HSS-E), which contains added vanadium for enhanced wear resistance and toughness, making it suitable for continuous use in industrial settings. The flute design features a 30-degree helix angle, which promotes efficient chip evacuation, reducing heat buildup and extending tool life. The tip is a 135-degree split point, which self-centers quickly and ensures accurate hole placement, even in hard materials. The bit is also surface-treated with a nitride coating, which provides corrosion resistance and reduces friction, further improving its performance. Available in sizes from 3mm to 16mm, the A117 is a reliable choice for general metalworking applications.

For drilling into stainless steel and high-alloy steels, the Dormer Pramet A127 Cobalt Triangular Twist Drill Bit is an excellent option. This bit is constructed from cobalt high-speed steel (HSS-Co), which contains 5% cobalt, enhancing its heat resistance and allowing it to maintain hardness at higher temperatures than standard HSS. This makes it ideal for drilling into materials that generate high levels of heat during cutting. The triangular shank is reinforced to handle high torque, preventing distortion under heavy loads. The flute design is optimized for deep-hole drilling, with a parabolic shape that ensures chips are efficiently cleared from the hole, even at depths greater than five times the bit diameter. The tip is precision-ground to a 135-degree angle, with sharp cutting edges that reduce cutting forces and improve surface finish. The A127 is available in sizes from 4mm to 20mm, making it suitable for heavy-duty industrial applications.

Dormer Pramet also offers the Dormer Pramet A140 Titanium-Coated Triangular Twist Drill Bit for high-performance drilling. This bit features a titanium nitride (TiN) coating that increases surface hardness and reduces friction, making it suitable for drilling into a wide range of materials, including steel, aluminum, and copper. The triangular shank ensures a secure fit, while the flute design features a variable helix angle—steeper near the tip for fast chip removal and shallower toward the shank for stability. The 135-degree split point tip is self-centering and starts quickly, reducing setup time and improving accuracy. The bit is available in sizes from 2mm to 13mm, making it a versatile choice for precision machining tasks in aerospace, automotive, and general engineering.

Guhring Triangular Twist Drill Bits
Guhring, a German manufacturer with a reputation for precision and innovation, produces a range of high-performance triangular twist drill bits designed for demanding industrial applications. The brand’s commitment to research and development ensures that its bits incorporate the latest technologies to deliver superior results.

The Guhring 6000 Series Triangular Shank Twist Drill Bit is a premium model designed for general-purpose drilling in steel, cast iron, and non-ferrous metals. The bit features a triangular shank that provides a secure grip in drill chucks, ensuring efficient power transfer and reducing slippage. It is made from high-speed steel (HSS-E), which is heat-treated to achieve a high hardness level, making it resistant to wear and suitable for continuous use. The flute design is optimized for chip evacuation, with a parabolic shape that ensures debris is cleared from the hole quickly, reducing heat and friction. The tip is a 135-degree split point, which self-centers and starts drilling immediately, eliminating the need for pre-drilling. The bit is also coated with a thin layer of titanium nitride (TiN), which enhances wear resistance and reduces friction, extending its lifespan. Available in sizes from 1mm to 20mm, the 6000 Series is a favorite among precision engineers for its consistent performance.

For drilling into high-strength materials such as stainless steel and nickel alloys, Guhring offers the Guhring 6500 Series Cobalt Triangular Twist Drill Bit. This bit is constructed from cobalt high-speed steel (HSS-Co) with 8% cobalt content, providing exceptional heat resistance and allowing it to maintain its hardness at temperatures up to 600°C. This makes it ideal for drilling into materials that generate high levels of heat during cutting. The triangular shank is reinforced with a hardened core, ensuring strength and stability under heavy torque. The flute design features a variable helix angle, with a steeper angle near the tip for fast chip removal and a shallower angle toward the shank for improved rigidity during deep drilling. The tip is precision-ground to a 135-degree angle, with specially sharpened cutting edges that reduce cutting forces and improve surface finish. The 6500 Series is available in sizes from 3mm to 25mm, making it suitable for heavy-duty industrial applications in aerospace and power generation.

Guhring also offers the Guhring 7000 Series Titanium-Aluminum-Nitride (TiAlN) Coated Triangular Twist Drill Bit for maximum performance. This bit features a TiAlN coating, which offers superior wear resistance and high-temperature stability compared to TiN coatings, making it suitable for high-speed drilling in tough materials. The triangular shank ensures a secure fit, while the flute design is optimized for high-speed operations, with a smooth surface finish that reduces friction and improves chip flow. The 135-degree split point tip is self-centering and stays sharp longer, reducing the need for frequent sharpening. Available in sizes from 2mm to 16mm, the 7000 Series is designed for professionals who demand the highest levels of precision and durability in their drilling tools.

Conclusion
Triangular twist drill bits represent a specialized and versatile category of drilling tools, offering unique advantages in terms of grip, torque transmission, and heat dissipation. The triangular shank or cutting edge geometry, combined with advanced materials and coatings, makes these bits suitable for a wide range of applications across industries such as metalworking, woodworking, construction, and automotive repair. Leading brands like Bosch, DeWalt, Makita, Irwin, Milwaukee, Dormer Pramet, and Guhring have developed extensive lineups of triangular twist drill bits, each tailored to specific materials and drilling conditions, ensuring that there is a solution for every task.

From general-purpose HSS bits for everyday drilling to cobalt and titanium-coated models for tough metals, these bits deliver consistent performance, precision, and durability. Whether you are a professional machinist, a construction worker, or a DIY enthusiast, understanding the features and applications of these models can help you select the right tool for the job, ensuring efficient, accurate, and long-lasting results. As technology continues to advance, we can expect further innovations in triangular twist drill bit design, with even better materials, coatings, and geometries to meet the evolving needs of the industry.