Osg 4100003211 Thread Mill 1/4-20 3 Flute Solid Carbide

Product Description

The OSG 4100003211 is a solid carbide helical flute thread mill designed for cutting 1/4-20 UNC internal threads in a single helical pass. With 3 flutes and a 0.1800-inch cutting diameter, this tool produces accurate thread forms in ferrous and non-ferrous materials on CNC machining centers. The EXO coating extends tool life by reducing friction and heat buildup at the cutting edge. A 0.2500-inch minimum nominal diameter and 0.5510-inch length of cut suit it for through and blind-hole threading applications where tap breakage risk must be eliminated. It is classified as a long-reach thread mill in the OSG Series 41000 lineup.

This thread mill is used in precision machining environments including aerospace, automotive, mold and die, and general manufacturing shops. It is suited for CNC machining centers capable of executing helical interpolation. Right-hand flute direction and 20 TPI align with standard UNC 1/4-20 fastener specifications, making it a common choice for fixture plates, jigs, and structural hardware applications where clean thread form and size consistency are required.

Key Features

• Solid carbide construction for rigidity and wear resistance in hard and abrasive materials
• EXO coating reduces friction and extends tool life at elevated cutting speeds
• 3-flute helical design produces full thread form in a single CNC helical interpolation pass
• Long-reach thread mill type allows access in deeper or offset bore configurations
• Right-hand flute direction compatible with standard CNC thread milling cycles
• No coolant-through requirement simplifies setup on standard machining centers

Compatibility

Designed for cutting 1/4-20 UNC threads on CNC machining centers capable of helical interpolation. Minimum nominal bore diameter of 0.2500 inches required for engagement.

Installation Notes

Thread milling with this tool requires a CNC machining center programmed for helical interpolation — do not use on manual mills or drill presses. Confirm spindle speed, feed rate, and helix pitch in the CAM program before cutting. Secure the 1/4-inch shank in a precision collet or end mill holder to minimize runout, which directly affects thread accuracy. Follow the tool manufacturer's recommended cutting parameters for the specific workpiece material and consult applicable shop safety procedures when handling carbide tooling.