Internal Tool 69-4090 Tapered End Mill 3 Flute Solid Carbide

Product Description

The INTERNAL TOOL 69-4090 is a solid carbide tapered end mill designed for precision milling of ferrous metals, stainless steel, cast iron, and super alloys including titanium. It features a 30-degree taper angle per side and a small end diameter of 0.125 inches, making it well-suited for tapered pocket milling, engraving, and draft-angle profiling. The 3-flute helical design with right-hand flute direction provides efficient chip evacuation at moderate feed rates. The bright, uncoated finish is standard for carbide tools used in dry cutting or with flood coolant on harder workpiece materials. Overall length is 3 inches with a 0.5-inch shank diameter.

This end mill is intended for use in CNC machining centers and manual mills where tapered geometry is required. Primary workpiece materials include steel, stainless steel, cast iron, and super alloys and titanium, corresponding to ISO material groups P, M, K, and S. Typical applications include die and mold work, angled wall features, and tapered slot milling. The 0.325-inch length of cut and micrograin carbide construction support consistent performance in short-reach, high-accuracy operations. It is not center-cutting and should not be used for direct plunge entry.

Key Features

• 30-degree taper angle per side with 60-degree included angle for accurate draft features
• Micrograin solid carbide construction for extended tool life in hard and abrasive materials
• 3-flute helical design with right-hand cut for efficient chip removal
• 0.125-inch small end diameter and 0.5-inch large end diameter across 0.325 inches of cut length
• Bright, uncoated finish suitable for use with flood coolant or dry cutting
• 15-degree helix angle optimized for stability in short-reach tapered cuts

Compatibility

Designed as a direct-fit replacement for INTERNAL TOOL Series 69 tapered end mills. Fits standard 0.5-inch collet chucks and end mill holders used in CNC machining centers and manual milling machines.

Installation Notes

Installation should be performed by a qualified machinist or CNC tooling technician. Ensure the spindle is fully stopped and the machine is in a safe, de-energized state before changing tooling. Seat the 0.5-inch shank fully and evenly in the collet or end mill holder and torque the retention hardware to the tool holder manufacturer specification. This tool is not center-cutting and requires a pre-drilled or pre-milled entry point before lateral engagement.