Hertel 88558259 No. 27 Drill Bit 135 Split Point Hss

Product Description

The HERTEL 88558259 is a No. 27 wire gauge threaded shank drill bit designed for precision drilling in low-tensile strength materials. It measures 0.1440 inches in diameter with a 2.125-inch overall length and a 1.125-inch flute length. The 135-degree split point geometry reduces walking at entry and lowers thrust required to start the hole. The bit carries a 1/4-28 threaded hex shank for positive engagement in threaded chuck systems. An oxide finish provides light surface protection. Right-hand cutting with a regular spiral flute suits standard drilling operations. This bit is spec-referenced to NAS 965 and is installed by machinists, maintenance technicians, and metalworking tradespeople.

This drill bit is suited for use in sheet metal, soft steel, aluminum, and other low-tensile strength materials in light production, maintenance, and repair applications. The web-thinned, tapered web construction reduces cutting resistance and improves chip evacuation. The 1/4-28 threaded hex shank is compatible with threaded quick-change chuck systems common in handheld and bench-mounted drilling equipment. It is a general-purpose HSS bit for both shop and field use where controlled hole size to No. 27 wire gauge is required.

Key Features

• No. 27 wire gauge diameter: 0.1440 inches for precise hole sizing
• 135-degree split point reduces drill walking and lowers entry thrust
• Web-thinned, tapered web improves chip clearance and cutting efficiency
• 1/4-28 threaded hex shank for positive retention in quick-change chuck systems
• High speed steel construction with oxide coating for general-purpose durability
• NAS 965 specification compliance for aerospace and precision maintenance applications

Compatibility

Designed for use in threaded quick-change chuck systems accepting a 1/4-28 hex shank. Suitable for drilling low-tensile strength materials including soft steel, aluminum, and similar metals where a No. 27 wire gauge hole diameter is specified.

Installation Notes

Installation is performed by machinists or qualified maintenance technicians. Ensure the drill press, hand drill, or power tool is fully de-energized and the chuck is secured before inserting or removing the bit. Verify thread engagement on the hex shank is complete before applying drilling force. Wear appropriate eye protection and secure the workpiece before drilling.