Cleveland C46109 Countersink 3/8 in 90 Deg 1 Flute Hss

Product Description

The CLEVELAND C46109 is a single-flute high speed steel countersink designed for creating conical seat profiles in metal workpieces. With a 3/8 inch head diameter and a 90-degree included angle, this tool produces clean, accurate chamfers suited for flathead fastener seating and deburring operations. The straight-cylindrical shank measures 1/4 inch in diameter, providing a secure grip in standard drill chucks and collet holders. An oxide coating helps reduce friction during cutting and extends tool life under normal shop conditions. Machinists, tool-and-die workers, and maintenance technicians install this countersink in drill presses, CNC machines, and handheld power drills.

This countersink is intended for use on carbon steel and cast iron workpieces. The single-flute design reduces chatter and produces a smoother finish compared to multi-flute alternatives, making it a practical choice for precision countersinking in low-to-medium volume production and repair work. Typical applications include preparing bolt holes for flathead cap screws, deburring drilled holes, and chamfering hole entries before tapping. The 90-degree angle matches the most common flathead machine screw standards used in general metalworking.

Key Features

• 3/8 inch head diameter with a 90-degree included angle for standard flathead fastener seating
• Single-flute geometry reduces chatter and promotes a cleaner surface finish
• High speed steel construction provides durability in carbon steel and cast iron applications
• Oxide finish reduces friction and provides moderate corrosion resistance
• 1/4 inch straight-cylindrical shank fits standard chucks and collet holders
• Right-hand cutting direction compatible with conventional clockwise-rotation tooling setups

Compatibility

Designed for countersinking operations in carbon steel and cast iron. Compatible with standard drill chucks and collet systems accepting a 1/4 inch straight-cylindrical shank.

Installation Notes

This tool is installed by machinists and maintenance technicians using standard drill press, CNC, or handheld power drill setups. Secure the shank firmly in the chuck or collet before operation and confirm the workpiece is clamped to prevent movement. Use appropriate cutting fluid for steel to extend tool life and improve surface finish. Always wear eye protection and follow shop safety protocols when operating rotary cutting tools.