Guhring 9055110040400 Jobber Drill Bit No 21 Solid Carbide

Product Description

The GUHRING 9055110040400 is a solid carbide jobber length drill bit in wire size No. 21 (0.1591 inches diameter) from the Series 5511 high-performance lineup. It features a 140-degree split point (SU type) with web thinning for self-centering entry, eliminating the need for a center punch on most applications. The FIREX coating extends tool life when cutting ferrous and cast materials at elevated speeds. With a 2-flute spiral design and an overall length of 74 mm (approximately 2.91 inches), this bit is built for productive, accurate drilling in demanding production environments. Licensed HVAC techs, machinists, and metalworking professionals rely on this geometry for consistent hole quality.

This drill bit is designed for drilling cast iron and steel workpieces in manufacturing, maintenance, and fabrication settings. The straight-cylindrical shank (6 mm diameter) seats securely in standard drill chucks and collet systems. A 5xD flute-to-diameter ratio and coolant-through capability make it well suited for CNC machining centers and drill presses where through-spindle coolant is available. The maximum drilling depth is 29.94 mm (approximately 1.18 inches), and the flute length is 36 mm (approximately 1.42 inches).

Key Features

• Solid carbide construction for rigidity and wear resistance in ferrous materials
• FIREX coating reduces friction and extends tool life on cast iron and steel
• 140-degree SU split point with web thinning for self-centering, no-wander entry
• Coolant-through design compatible with through-spindle coolant systems
• Right-hand cut, regular spiral flute for efficient chip evacuation
• Straight-cylindrical shank meets DIN 6535 and DIN 6537 L standards

Compatibility

Designed for use in standard drill chucks and collet holders accepting a 6 mm straight-cylindrical shank. Primary workpiece materials are cast iron (material code K) and steel (material code P). Conforms to DIN 6535 and DIN 6537 L shank and length specifications.

Installation Notes

This bit is installed by machinists and metalworking technicians in CNC machining centers, drill presses, or hand-held drilling equipment with appropriate chuck capacity. Secure the shank fully in the collet or chuck before operation and verify runout is within acceptable tolerance to protect the carbide from shock loading. When using coolant-through capability, confirm the machine spindle delivers adequate coolant pressure and flow before beginning the cut. Solid carbide is brittle compared to high-speed steel — avoid lateral loading or side forces that can cause chipping or breakage.