Precision Twist Drill 5999573 Reduced Shank Drill Bit

Product Description

The PRECISION TWIST DRILL 5999573 is a reduced shank twist drill bit engineered for general-purpose drilling in ferrous metals and a wide range of secondary materials. Built from high-speed steel (HSS) with a bright, uncoated finish, it features a 118-degree standard point angle suited for everyday production and maintenance drilling. The bit measures 1-3/16 inches (1.1875 inches decimal) in cutting diameter with a reduced 1/2-inch Weldon flat shank, allowing it to seat securely in standard 1/2-inch capacity chucks and drill presses. Right-hand spiral flutes clear chips efficiently during operation. Machinists, millwrights, and maintenance technicians install this bit in shop and field environments where a full-shank bit of this diameter would exceed the capacity of standard tooling.

This drill bit is suited for drilling ferrous metals as its primary workpiece material. Secondary compatible materials include aluminum, copper, magnesium, nickel, titanium, synthetic composites, and cermet. The reduced Weldon shank design makes it a practical choice in facilities where drill press spindles, magnetic drill units, or milling machine chucks are limited to 1/2-inch shank capacity but require hole sizes well above that diameter. The Series R57 designation identifies it within the Precision Twist Drill line of reduced shank general-purpose bits.

Key Features

• 1-3/16 inch (1.1875 inch) cutting diameter with a reduced 1/2-inch Weldon flat shank for compatibility with standard 1/2-inch capacity tooling
• 118-degree standard point angle for general-purpose drilling across a broad range of materials
• High-speed steel construction provides adequate hardness and toughness for ferrous and non-ferrous metals
• Bright/uncoated finish — suitable for applications where coating or lubricant is applied externally or coolant is not required
• 3-inch flute length with right-hand spiral for effective chip evacuation up to 3 inches drilling depth
• 3-flat Weldon shank geometry resists bit rotation and slippage under load

Compatibility

Designed as a general-purpose reduced shank drill bit compatible with 1/2-inch capacity chucks, drill presses, and magnetic drill units; primary workpiece materials are ferrous metals, with secondary compatibility covering aluminum, copper, magnesium, nickel, titanium, synthetic composites, and cermet per Series R57 specifications. Conforms to ANSI standards.

Installation Notes

Installation and operation should be performed by a qualified machinist or maintenance technician familiar with rotating cutting tools. Secure the Weldon flat shank fully in the chuck or collet before operation and confirm all set screws engage the flats to prevent slippage under load. Always power down and de-energize the drill press or milling machine before changing bits. Follow applicable shop safety procedures and wear appropriate eye protection when operating.