Scientific Cutting Tools TM187-20 Thread Mill 1/4-20

Product Description

The SCIENTIFIC CUTTING TOOLS TM187-20 is a straight flute thread mill designed for cutting internal 1/4-20 UNC threads in a single helical pass. Built from submicron-grade solid carbide, it delivers the rigidity and edge retention required for threading hard or abrasive workpiece materials. The tool features a 0.187 inch cutting diameter, a 0.57 inch length of cut, and a 2.5 inch overall length. With 3 straight flutes and a bright finish, it is suited for CNC machining centers where accurate thread form and tool life are the priority. Machinists, toolroom technicians, and production CNC operators are the primary users.

This thread mill is intended for internal threading operations on CNC milling machines and machining centers. It is used to produce 1/4-20 UNC internal threads in applications where rigid tapping is impractical or where thread quality and positional accuracy are critical. The 1/4 inch shank diameter fits standard ER collet chucks and small-bore tool holders commonly found in both job shop and production environments. It is appropriate for threading a range of materials including aluminum, steel, stainless, and engineering plastics.

Key Features

• Cuts 1/4-20 UNC internal threads at 20 teeth per inch with a single helical interpolation pass
• Submicron-grade solid carbide construction for enhanced wear resistance and edge stability
• 0.187 inch cutting diameter with 0.57 inch length of cut accommodates standard 1/4-20 thread depths
• 3 straight flutes with bright finish for clean chip evacuation and reduced buildup
• 1/4 inch shank diameter for compatibility with standard ER and precision collet tooling
• No coolant-through design suited for flood or mist coolant delivery external to the tool

Compatibility

Designed as an OEM-style thread milling solution for CNC machining centers capable of helical interpolation, using standard 1/4 inch collet or end mill holders accepting a 1/4 inch shank.

Installation Notes

Installation and use should be performed by a qualified CNC machinist or toolroom technician. Secure the shank in a precision collet or shrink-fit holder and verify runout before cutting. Program the tool path as a helical interpolation cycle matched to the 1/4-20 UNC thread form and the specific minor diameter of the workpiece. Confirm spindle speed, feed rate, and coolant delivery comply with the tool manufacturer recommendations and facility machining standards before running the first part.