Hertel 18753 Countersink 5/16 in 100 Degree 4 Flute Hss

Product Description

The HERTEL 18753 is a 4-flute countersink designed for creating clean, accurately angled seat profiles in metal and other hard materials. Built from high speed steel, it delivers reliable cutting performance in production and maintenance shop environments. The 100-degree included angle makes it suitable for flat-head fastener seating applications where that geometry is specified. With a 5/16-inch head diameter and matching 5/16-inch straight cylindrical shank, it fits standard drill chucks and collet holders without adapters. Machinists, toolroom techs, and maintenance tradespeople reach for this tool when deburring holes or preparing fastener seats on ferrous and non-ferrous workpieces.

This countersink is suited for use on drill presses, milling machines, and hand-held power drills in both job shop and field maintenance settings. The straight cylindrical shank seats securely in standard drill chucks across a range of machine types. The 100-degree included angle accommodates flat-head screw standards that call for that specific geometry. It is appropriate for light to moderate production work in metal fabrication, HVAC equipment assembly, electrical enclosure work, and general mechanical maintenance where precise countersinking is required.

Key Features

• 5/16-inch head diameter for compact countersinking in tight clearance areas
• 100-degree included angle matches flat-head fastener seat specifications requiring that geometry
• 4-flute design promotes smooth cutting action and reduces chatter on entry
• High speed steel construction provides heat resistance and durability across ferrous and non-ferrous materials
• Straight cylindrical shank fits standard drill chucks and collet holders without adapters

Compatibility

Designed as a general-purpose countersink compatible with standard drill chucks and collet holders accepting a 5/16-inch straight cylindrical shank, suitable for use on drill presses, milling machines, and portable power drills.

Installation Notes

Machinists and maintenance technicians should secure the shank fully in the chuck or collet before operation and verify the spindle is at a complete stop before tool changes. Use cutting fluid appropriate for the workpiece material to extend tool life and improve finish quality. Follow applicable shop safety standards and machine guarding requirements when operating rotary cutting tools.