Hertel 74131509 Screw Machine Drill Bit 17/64 in Cobalt

Product Description

The HERTEL 74131509 is a screw machine length drill bit designed for high-production drilling applications where rigidity and heat resistance are critical. Built from cobalt tool steel with a TiAlN coating, it handles hard and abrasive materials that would quickly wear out standard HSS bits. The split point geometry at 135 degrees reduces walking and lowers thrust force at the start of the cut, eliminating the need for a center punch on most materials. At 2.625 inches overall length, the stub-length body provides increased stiffness compared to a jobber-length bit, reducing deflection in tight-clearance setups.

This bit is suited for use in CNC machining centers, drill presses, and screw machines operating on steel, stainless steel, cast iron, and other hard ferrous metals. The straight cylindrical shank fits standard drill chucks and collet holders without modification. Web-thinned construction with a parallel web configuration reduces cutting resistance. Right-hand spiral flutes evacuate chips efficiently, keeping the cut clean during through-hole and blind-hole operations in production environments. Machine shops, maintenance technicians, and metalworking trades are the primary users of this type of tooling.

Key Features

• Cobalt tool steel construction provides heat resistance beyond standard HSS for harder workpiece materials
• TiAlN coating extends tool life in dry and high-speed cutting conditions
• 135-degree split point reduces thrust and eliminates bit walking on entry
• Web-thinned parallel web lowers cutting resistance and improves chip clearance
• Stub screw machine length body increases rigidity and minimizes deflection
• Right-hand spiral flutes promote efficient chip evacuation from the hole

Compatibility

Designed as a screw machine length replacement or production-use drill bit for applications requiring a 17/64 inch diameter hole in ferrous and hard materials. Fits any drill chuck or collet holder accepting a straight cylindrical shank in the 0.2500 to 0.3000 inch decimal inch size range.

Installation Notes

Install the bit securely in the chuck or collet and verify runout before beginning a production run. Ensure the drill press or machining center spindle speed is appropriate for the workpiece material and bit diameter. Secure the workpiece with proper fixturing before drilling. Inspect the cutting edges and coating condition regularly, as cobalt bits can chip if used at incorrect feeds and speeds on interrupted cuts.