Hertel 91197350 Roughing End Mill 3/8 in 4 Flute Cobalt

Product Description

The HERTEL 91197350 is a single-end roughing end mill designed for aggressive material removal in milling applications. Manufactured from M42 cobalt high-speed steel with a bright, uncoated finish, it delivers the toughness needed for interrupted cuts and hard-to-machine alloys. The 3/8 inch diameter cutter carries 4 right-hand flutes ground with a fine pitch geometry, allowing rapid chip evacuation while reducing chatter. With a 1.5 inch length of cut and a 3.25 inch overall length, this tool is sized for general-purpose roughing passes on knee mills, CNC machining centers, and manual vertical mills. It is center-cutting, enabling direct plunge entry without a pilot hole.

This end mill is suited for roughing operations on ferrous metals, stainless steels, and heat-resistant alloys where cobalt tooling outperforms standard HSS. Typical applications include slotting, profiling, and pocket roughing in job shop, maintenance, and production environments. The 3/8 inch shank diameter matches standard collet and end mill holder sizes common on both manual and CNC equipment. Licensed machinists, tool-and-die technicians, and maintenance mechanics are the primary users.

Key Features

• M42 cobalt construction for improved red-hardness and wear resistance versus standard HSS
• Fine-pitch, 4-flute roughing geometry reduces cutting forces and chatter during aggressive passes
• Center-cutting design allows direct plunge entry without pre-drilling
• Right-hand cut and right-hand flute direction compatible with standard spindle rotation
• Bright, uncoated finish suitable for use with or without cutting fluid
• 3/8 inch shank diameter matches 3/8 inch collets and end mill holders

Compatibility

Designed as a standard 3/8 inch single-end roughing end mill for use in any milling machine or machining center equipped with a compatible 3/8 inch collet, end mill holder, or Weldon-style holder.

Installation Notes

Install and remove tooling only with the machine spindle fully stopped and the machine in a locked-out, energy-isolated state per applicable lockout/tagout procedures. Seat the shank fully into the holder to the recommended engagement depth before tightening the set screw or collet nut. Inspect the cutting edges for chips or wear before each use and replace the tool if damage is observed. Cutting fluid or mist coolant is recommended when machining ferrous and stainless materials to extend tool life.