Keo 919-000-383 Countersink 1/2 in 90 Degree 6 Flute Hss

Product Description

The KEO 919-000-383 is a single-end, 6-flute countersink designed for producing clean, accurately angled seat profiles in metal workpieces. Built from high-speed steel (HSS), it delivers consistent performance across a range of ferrous and non-ferrous materials. The 90-degree included angle and 45-degree centerline angle are standard for most fastener-seat applications. The straight-cylindrical shank measures 3/8 inches in diameter and 1 inch in length, making it compatible with standard drill chucks and collet holders. Right-hand cut geometry is suited for conventional CNC and manual drill press setups. No pilot is included, so the tool relies on an existing center hole or operator skill for precise positioning.

This countersink is used in machine shops, fabrication environments, and production lines where consistent fastener-seat prep is required. It is appropriate for countersinking screw clearance holes in steel, aluminum, brass, and similar materials. The 1/2-inch head diameter suits applications where a moderate-sized chamfer is needed ahead of flat-head or oval-head fasteners. Machinists and tool-and-die tradespeople are the primary installers and users of this tool in both manual and CNC-assisted operations.

Key Features

• 1/2-inch head diameter for moderate-scale countersinking work
• 90-degree included angle matches the most common flat-head fastener seat standard
• 6-flute design distributes cutting load and promotes a smoother finish
• High-speed steel construction provides wear resistance across a broad range of workpiece materials
• Straight-cylindrical 3/8-inch shank fits standard drill chucks and collet holders without adapters
• Right-hand cut geometry compatible with conventional drilling equipment and CNC spindles

Compatibility

Designed as an OEM-style single-end countersink for use in standard 3/8-inch drill chucks and collet systems on drill presses, milling machines, and CNC machining centers performing countersinking operations.

Installation Notes

This tool is installed and operated by machinists and precision metalworking tradespeople. Always secure the workpiece firmly before beginning the countersinking operation. Ensure the spindle is fully stopped before inserting or removing the tool from the chuck or collet. No pilot is included, so a pre-drilled center hole is recommended for accurate seat placement and to prevent wandering.