The Robert Charles Plain Shank Counterbore is a high-performance cutting tool designed for professionals who require precise, clean counterbores with dependable durability. Crafted from M35-HSS-E with 5% cobalt, it delivers excellent heat resistance and wear life for demanding metalworking tasks.

• Material: M35 HSS-E with 5% cobalt for enhanced heat resistance, edge strength, and extended cutting life.
• Shank Type: Plain shank designed for easy fitment in standard tool holders, supporting stable, repeatable machining.
• Cutting Geometry: Precision-ground edges optimized for clean, burr-free counterbores and efficient chip evacuation.
• Pilot Size: 0.125 in pilot to guide entry and promote accurate hole alignment during countersinking.
• Cap Screw Size: Compatible with #5 cap screw interfaces for flush-mount applications.
• Applications: Ideal for precision engineering, automotive assemblies, and general workshop use where durability and consistent results matter.

This counterbore is built to deliver repeatable depths and smooth faces, reducing finishing work and improving part fit. The cobalt-enhanced alloy maintains hardness at elevated temperatures, enabling more aggressive feeds without compromising edge life. The plain shank simplifies tool changes and minimizes setup time, helping you stay productive in both small shops and full-scale shops. Use it for precise bolt-hole counterboring in assemblies, brackets, and fixtures where reliable performance is essential.