Precision Twist Drill 5999959 Reduced Shank Drill Bit

Product Description

The PRECISION TWIST DRILL 5999959 is a reduced shank twist drill bit designed for general-purpose hole drilling in ferrous metals and a range of non-ferrous materials. The bit measures 21/32 inch (0.6562 inch) in diameter with a 1/2 inch straight-cylindrical reduced shank, allowing it to seat in standard 1/2 inch chucks even though the cutting diameter is larger. Overall length is 6 inches with a 3 inch flute length. Constructed from high speed steel (HSS) with a bright uncoated finish, this bit is part of the Series R56 lineup and carries a 118-degree standard point angle suited to a wide range of shop and field drilling tasks.

This drill bit is intended for use in metal fabrication, HVAC rough-in, plumbing, electrical, and mechanical service work where holes larger than 1/2 inch diameter are needed but only a 1/2 inch chuck is available. The reduced shank design is a practical solution for tradespeople working with standard-capacity drills on the job site. Right-hand spiral flutes evacuate chips efficiently during drilling. Compatible workpiece materials include ferrous metals as the primary application, with secondary suitability for aluminum, copper, magnesium, nickel, titanium, and certain synthetic materials.

Key Features

• 21/32 inch cutting diameter with 1/2 inch reduced straight-cylindrical shank for use in standard 1/2 inch chucks
• 118-degree standard point angle for general-purpose drilling in metals and non-ferrous materials
• High speed steel construction provides durability across a broad range of workpiece materials
• Bright uncoated finish — no coating to chip or delaminate during heavy use
• Right-hand spiral flutes with regular spiral promote consistent chip evacuation
• Series R56, ANSI standards compliant

Compatibility

Designed as a general-purpose replacement or stock drill bit for use in any 1/2 inch keyed or keyless drill chuck. Primary workpiece material is ferrous metal; secondary compatible materials include aluminum, copper, magnesium, nickel, titanium, cermet, and synthetic materials per manufacturer specifications.

Installation Notes

This bit is installed and operated by machinists, pipefitters, electricians, HVAC technicians, and general trade professionals using corded or cordless drills and drill presses. Secure the reduced shank fully in the chuck and verify the chuck is tightened before operation. Use appropriate cutting fluid or lubricant when drilling ferrous metals to extend bit life, unless the workpiece material or application requires dry cutting. Always wear eye protection and secure the workpiece before drilling.