Hertel 74130733 Cobalt Screw Machine Drill Bit Size 21

Product Description

The HERTEL 74130733 is a cobalt screw machine length drill bit designed for high-speed drilling in tough materials including alloy steels, stainless steel, and hard cast iron. Built to the HSCO135 series standard, this bit features a 135-degree split point that reduces walking and allows for self-centering without a center punch. The stub-length body provides added rigidity compared to jobber-length bits, reducing deflection in short-hole applications. With 2 right-hand spiral flutes and a web-thinned parallel web configuration, the 74130733 delivers efficient chip evacuation and consistent cutting performance across production and maintenance drilling operations.

This bit is suited for use in drill presses, CNC machining centers, and hand-held power tools where short overall length and rigidity are required. The 2.125-inch overall length and 1.0625-inch flute length make it appropriate for shallow-hole work in metal fabrication, machine shops, and production environments. It is a right-hand cutting bit with a straight cylindrical shank, compatible with standard 3-jaw chucks and collet holders. Trade machinists and maintenance technicians commonly select screw machine length bits for close-tolerance work in confined spaces or when a rigid setup is critical.

Key Features

• Cobalt construction for heat resistance and extended tool life in hard and abrasive materials
• 135-degree split point for self-centering and reduced thrust force on entry
• Web-thinned parallel web design improves chip flow and reduces cutting resistance
• Screw machine (stub) length provides greater rigidity and less deflection than jobber-length bits
• Right-hand, regular spiral fluting with 2 flutes for efficient chip evacuation
• Straight cylindrical shank fits standard chucks and collet systems without modification

Compatibility

Designed as a screw machine length drill bit for use in standard 3-jaw chucks and collet tool holders across drill presses, CNC machines, and handheld power drills. Fits applications requiring Size 21 wire gauge diameter (0.1590 inch) in the 0.1500 to 0.2000 inch drill bit size range.

Installation Notes

Install into a properly rated chuck or collet holder and verify shank seating before operation. Ensure the workpiece is firmly secured before drilling to prevent rotation or movement. Use appropriate cutting fluid or coolant for the material being drilled, noting this bit does not support through-coolant delivery. Inspect the cutting edges and split point for wear or chipping before each use and replace if performance degrades.