Irwin 12412 5/8″ High Speed Steel Black Oxide Countersink Drill Bit

The Irwin 12412 5/8″ High Speed Steel Countersink Drill Bit is designed for producing clean, accurate countersunk holes in a wide range of machinable materials. Built from industrial-grade high speed steel, this countersink is intended for repeated use in metalworking, woodworking, and general fabrication environments. The larger 5/8-inch diameter makes it suitable for applications requiring wider fastener seating or larger flat-head screws.

This countersink features a precision ground 82-degree cutting angle, which matches the standard angle used for most flat-head fasteners in metal, wood, and plastic. Its five-flute cutting design helps reduce vibration during operation, resulting in smoother cuts, improved control, and longer tool life. A black oxide finish adds corrosion resistance and reduces friction during cutting. With a 1-23/32-inch overall length and a 1/4-inch round shank, the Irwin 12412 fits most handheld drills and drill presses, making it a dependable option for both shop and jobsite use.

Irwin 5/8″ High Speed Steel Black Oxide Countersink Drill Bit At a Glance

• 5/8″ Countersink Diameter: Supports larger flat-head fasteners and hardware
• 82° Cutting Angle: Matches standard fastener profiles for flush seating
• High Speed Steel Construction: Provides durability and consistent cutting performance
• Five-Flute Design: Reduces chatter and vibration for smoother operation
• Black Oxide Finish: Improves corrosion resistance and cutting efficiency
• 1/4″ Round Shank: Compatible with most drills and drill presses
• Precision Ground Cutting Edges: Delivers clean, repeatable countersinks

Markets

• Metal Fabrication Shops: Used for countersinking fasteners in steel, aluminum, and soft metals
• Construction and Renovation: Ideal for hardware installation and structural fastening tasks
• Woodworking and Cabinet Shops: Produces clean countersinks in hardwoods, softwoods, and panels
• Automotive and Equipment Repair: Supports flush fastener installation on brackets and assemblies
• Maintenance and Facility Services: Useful for general repair across mixed materials
• Trade Schools and Educational Programs: Helps demonstrate proper drilling and countersinking techniques

Contractors, fabricators, and maintenance technicians depend on accurate countersinking to ensure fasteners sit flush and assemblies fit correctly. The Irwin 12412 countersink drill bit provides consistent results when working with larger fasteners across metal, wood, and plastic. Its precision ground 82-degree cutting angle reduces the need for follow-up adjustments and helps maintain a clean finished surface.

The five-flute design minimizes vibration, allowing for better control and smoother cutting even in harder materials. For users switching between handheld drills and drill presses, the 1/4-inch round shank offers easy compatibility without adapters. Whether used in fabrication shops, on jobsites, or in maintenance departments, this countersink delivers reliable performance for everyday fastening preparation.

Irwin 12412 5/8″ High Speed Steel Black Oxide Countersink Drill Bit Features

• Industrial-Grade High Speed Steel: Provides strength and wear resistance for repeated use
• Precision Ground 82° Tip: Designed for standard flat-head fastener applications
• Five-Flute Cutting Geometry: Reduces vibration and improves cut quality
• Black Oxide Coating: Helps resist corrosion and reduce friction during cutting
• Machinable Material Compatibility: Suitable for iron, steel, soft metals, plastics, and wood

Irwin 12412 5/8″ High Speed Steel Black Oxide Countersink Drill Bit Includes

• (1) 5/8″ High Speed Steel Countersink Drill Bit

Irwin 12412 5/8″ High Speed Steel Black Oxide Countersink Drill Bit Specifications

• Diameter: 5/8 in.
• Cutting Angle: 82 Degrees
• Overall Length: 1-23/32 in.
• Shank Size: 1/4 in.
• Shank Type: Round
• Material: High Speed Steel
• Finish: Black Oxide

Why Customers Choose the Irwin 5/8″ High Speed Steel Black Oxide Countersink Drill Bit

Customers choose the Irwin 12412 countersink drill bit for its ability to deliver smooth, accurate countersinks when working with larger fasteners and wider seating requirements. The high speed steel construction stands up to frequent use in metalworking and woodworking applications, while the black oxide finish helps extend service life in shop and jobsite conditions.

The 82-degree cutting angle aligns with common flat-head screws, reducing rework and helping installers achieve consistent results. With a five-flute design that limits vibration and a 1/4-inch round shank that fits standard drills, this countersink is a practical choice for technicians, contractors, and maintenance crews who need reliable performance across a variety of materials and fastening tasks.