Selecting the optimal counterbore is crucial for achieving professional and precise results in woodworking, metalworking, and various construction projects. A well-chosen tool ensures that fasteners sit flush or below the surface, preventing damage and improving the aesthetic finish of your work. Understanding the key features and types available will significantly impact the quality and efficiency of your drilling tasks.
- Supplied in a fitted case.
- 14 pilots with a 5/32" shank including 0.187, 0.204, 0.213, 0.229, 1/4, 17/64, 9/32, 5/16, 21/64, 11/32, 3/8, 25/64, 13/32 and 7/16.
- 6 counterbores including 5/16, 3/8, 7/16, 1/2, 9/16 and 5/8
- 1 Holder with a 3/8" shank.
- Inch Set (7 PC) : 6#, 8#, 10#, 1/4'', 5/16'', 3/8'', 1/2''
- High Speed Steel. Straight Shank.
- Cap screw counterbores are tools that are used to create a recess in a workpiece for the head of a cap screw. You might use a cap screw counterbore when you need to attach a component to your workpiece using cap screws, and the component has a thickness...
- Another reason you might use a cap screw counterbore is if you want to create a flush or countersunk appearance for the heads of the cap screws on your workpiece. A cap screw counterbore allows you to create a recess in the workpiece that is sized to fit...
- 【Main purpose】: Countersunk end mill is a specially manufactured tool, mainly used to cut holes that allow bolts or screw heads to be screwed into.
- 【High precision】: The cutting hole and bottom hole of this tool have high alignment accuracy. Because of its high production efficiency, it is often used in the machining industry.
- 【High-quality】: The Counterbore End Mill Cutters is made of hard high-speed steel, with high toughness, wear , and high hardness for high-speed cutting; it is usually used for assembly on a milling machine.
- 【More time-saving】: Countersunk cutters reduce the time to change tools, improve the efficiency of machine actuator movement and save manufacturing time.
- 【Unique Two-Flute Design】Featuring a dual-edge cutting design, these countersink drill bits eliminate chatter and ensure smooth, precise finishes. Compared to single-blade bits, they offer faster cutting, ideal for larger or deeper countersinks.
- 【Upgraded 12-Piece Set】This EZARC countersink drill bit set includes 5pcs Countersink bits -#4 (5/64″), #6 (3/32″), #8 (7/64″), #10 (1/8″), #12 (9/64″);5pcs Replaceable drill bits; 1pc 60mm Magnetic Extension bit holder; 1pc Allen...
- 【Strong and Durable】Crafted from premium titanium-coated high-speed steel, the countersink bits are perfect for use on both softwood and hardwood. The upgraded chamfer blade with a stepped design minimizes cutting resistance and maximizes durability.
- 【Efficient and Clean Drilling】Designed with sharp blades and an 82-degree countersink angle, these bits deliver fast, clean pilot holes for a snug screw fit. All-in-one drilling, countersinking, and counterboring maximize efficiency.
- 【High Speed Steel】Made of HSS-AL hard high speed steel, with high toughness, abrasion resistance, high-speed cutting for the high hardness.
- 【Professional Tool】Mainly used to cut holes that allow bolts or screw heads to be screwed into. Can be processed directly or finely processed to the heat treatment tool.
- 【High Alignment Precision】The end mill cutter cuts hole and bottom hole with high alignment precision. Due to its high production efficiency, it is commonly used in the machining industry.
- 【Improve Efficiency】Reduce the time of changing tool, improve the efficiency of machine actuator movement, and save tool making time.
- Premium Materials: Made from TCT alloy (Tungsten Carbide Tipped) Tapered Flute and HSS Drill Bits that resists bending and maintains sharpness. Precision-ground helical design for clean, smooth countersinks and counterbores perfect for 82-degree screws
- Adjustable Depth and Less Wear: Upgraded aluminum countersink depth stop collar provides exact drilling control and reduces wear versus traditional collars. Set depth easily with included wrench
- Multi-Material Mastery: The woodworking tools perfect for wood, plywood, MDF, particle board, aluminum, and other materials. This countersink drill bit set handles diverse woodworking and drilling projects
- Complete Bits Kit: Includes 5 two-flute wood drill bit set (1/8"×3/8", 9/64"×3/8", 5/32"×3/8", 11/64"×1/2", 3/16"×1/2") covering most common screw sizes, plus 1 wrench and 1 stop collar with 1/4 inch hex shank
- 7-piece metric cap screw counterbore set includes sizes M3, M4, M5, M6, M8, M10, and M12
- High speed steel solid counterbores with 3-flute design and straight shank construction for counterboring cap screw recesses
- Listed dimensions include pilot diameter, cutting diameter, shank diameter, and overall length for each tool in the set
- Designed to machine flat-bottom recesses for cap screw heads in compatible drill press and milling machine setups
- Mix and match any counterbore drill with any pilot in this set; Includes a straight shank holder with a 3/8" shank diameter and 3-5/8" overall length
- Counterbore Sizes: 5/16", 3/8", 7/16", 1/2", 9/16", and 5/8"
- Pilot Sizes: 0.187", 0.204", 0.213", 0.229", 1/4", 17/64", 9/32", 5/16", 21/64", 11/32", 3/8", 25/64", 13/32", and 7/16"
- M2 high-speed steel offers an excellent combination of toughness, wear resistance, and red hardness
- Countersink Drill Bit Set 5 pc #4#6#8#10#12: Reliable countersink drill bits secured with pin in 1/4" hex shank; Counter sink drill bit for wood to predrill pilot hole drill bit for screw #4(7/64"), #6(9/64"), #8(11/64"), #10(3/16"), #12(7/32"); drill...
- Replacement tapered drill bits: FTG replacement wood countersink tapered bits are available for extended drill bit life; taper drill bits pointed tip and wide flute for drilling fast, clean pilot hole, ensures tight fit for screws; countersinks for wood
- Drill perfect tapered hole drill bit every time: Wood drill bit set with counter bore chamfer angle 82-degree, smooth countersinking in hard and soft wood, tapered holes for screws; adjustable wood countersink drill bits set ideal for woodworking; it come...
- Quality Steel: Third-party tested by US Accredited Lab: HSS M2 Grade 6542 countersink drill bit for wood with tapered drill bits; wood countersink bit with wider flute shape for increased chip flow; Counter sink drill bits with counter-bore and plugs size...
- Inch Size Versatility: Features sizes #6, #8, #10, 1/4'', 5/16'', 3/8'', and 1/2'', addressing a wide range of countersinking needs.
- Durable HSS Material: Constructed from high-speed steel (6542) for exceptional longevity and cutting performance.
- Efficient 3-Flute Design: Optimizes chip removal and finish quality, suitable for precision machining tasks.
- Universal Straight Shank: Ensures compatibility with various drilling and milling machines for versatile use.
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Last update on 2026-10-16 / Affiliate links / Images from Amazon Product Advertising API
How to Choose the Best Counterbores
Types, Materials, and Design
Counterbores come in various designs, each suited for specific tasks. Fixed pilot types ensure precise alignment with a pre-drilled hole of a specific diameter, while adjustable pilot designs offer versatility for different hole sizes. Stop collar counterbores integrate a collar to control the drilling depth, preventing over-drilling. The material of the tool is critical for its performance and longevity. High-Speed Steel (HSS) is a common choice for general-purpose applications in wood and softer metals. For harder materials like stainless steel, cast iron, or abrasive hardwoods, carbide-tipped or solid carbide tools offer superior wear resistance and extended tool life.
Sizing and Depth Control
Accurate sizing is paramount for a flush finish. The counterbore's main diameter should match the head diameter of the fastener you intend to use, ensuring it sits perfectly within the created recess. The pilot diameter, which guides the tool, must correspond precisely to the diameter of your pre-drilled clearance hole. Many tools are available with different shank styles, including straight shanks for standard drill chucks, hex shanks for quick-change systems, and Morse taper shanks for industrial machinery. For consistent results, especially in production environments, consider models that offer integrated or attachable depth stops to ensure uniform recess depth across multiple holes.
Application Considerations
The material of your workpiece dictates the optimal tool choice. For woodworking, most HSS or carbide-tipped options perform well, but specific designs might be better for preventing tear-out in delicate woods. When working with metals, harder alloys require more robust tools, often with specialized coatings to reduce friction and heat. Plastics and composites can be challenging, requiring tools with specific rake angles to prevent melting or chipping. Always ensure your drill press or handheld drill has adequate power and speed control for the chosen tool size and material, and use appropriate lubrication when working with metals to extend tool life and improve cut quality.
