Cleveland C52178 Square End Mill 0.375 in 4 Flute Cobalt

Product Description

The CLEVELAND C52178 is a cobalt square end mill designed for demanding material removal in ferrous and high-temperature alloy applications. Built from M42 cobalt high-speed steel, this double-end tool delivers extended tool life over standard HSS when cutting stainless steel, alloy steel, and high-temperature alloys. It runs a 0.375-inch cutting diameter with a 0.75-inch length of cut and features four spiral flutes with a 30-degree helix angle. The right-hand cut and right-hand flute geometry is the standard configuration for vertical machining centers and manual knee mills. Centercutting capability allows plunge entry without a pre-drilled pilot hole.

This end mill is suited for milling operations in job shops, production machining environments, and maintenance facilities where stainless steel and high-temp alloys are common workpiece materials. The HDC-4C series is a general-purpose cobalt line sized for 3/8-inch collets and tool holders. The straight cylindrical shank with Weldon flat accommodates both standard ER collet systems and side-lock holders, making it a flexible choice across common spindle setups. Regular-length geometry keeps the tool stiff and minimizes deflection in typical face, slot, and peripheral milling passes.

Key Features

• M42 cobalt steel construction for improved heat and wear resistance over standard M2 HSS
• Double-end design provides two usable cutting ends, extending service life per tool
• 30-degree helix spiral flute promotes chip evacuation and reduces cutting forces
• Centercutting geometry allows direct plunge milling without pre-drilling
• Weldon flat on straight shank compatible with side-lock and collet-style holders
• Uncoated finish suitable for use with cutting fluids or dry cutting depending on application

Compatibility

Designed for use in 3/8-inch ER collets, Weldon side-lock holders, or equivalent tool holding systems on vertical mills, CNC machining centers, and manual knee mills. Primary workpiece materials include high-temperature alloys, stainless steel, and steel (Material Codes M, P, S).

Installation Notes

Installation should be performed by a qualified machinist or tooling technician. Ensure the spindle is fully powered down and the machine is in a safe lockout state before changing tooling. Seat the Weldon flat against the set screw in side-lock holders to prevent axial pullout under load. Verify runout with a dial indicator after installation and before cutting to protect both the tool and the workpiece.