Harvey Tool 70046 Thread Mill 1/4-28 3 Flute Solid Carbide

Product Description

The HARVEY TOOL 70046 is a solid carbide helical flute thread mill designed for cutting 1/4-28 UNF threads in both internal and external applications. With 3 flutes and a 28 TPI configuration, it delivers consistent thread geometry on machining centers using standard helical interpolation routines. The cutting diameter is 0.180 inches and the length of cut is 0.500 inches, making it well suited for shallow-to-moderate depth thread milling operations. The bright, uncoated finish provides good performance across a range of workpiece materials without the heat buildup associated with some coated tooling. This tool is intended for use by machinists and tooling engineers running CNC milling equipment.

This thread mill is applicable to precision machining environments where a single tool must handle both internal and external 1/4-28 thread profiles. Typical applications include production milling of threaded features in aluminum, steel, stainless, and non-ferrous alloys where thread milling is preferred over tapping due to part fragility, blind hole constraints, or the need for thread size adjustability through cutter path offset. The minimum nominal diameter supported is 0.250 inches.

Key Features

• Cuts 1/4-28 UNF threads in both internal and external configurations with a single tool
• 3-flute solid carbide construction for rigidity and wear resistance
• 0.180 inch cutting diameter with 0.500 inch length of cut
• 28 teeth per inch for accurate UNF thread form
• Bright, uncoated finish suitable for a broad range of materials
• No coolant-through requirement — compatible with flood or mist coolant delivery

Compatibility

Designed for use in CNC milling machines accepting a 3/16 inch (0.1875 inch) shank diameter and programmed for helical interpolation to produce 1/4-28 UNF thread profiles.

Installation Notes

Thread mills of this type are installed by machinists in CNC machining centers using an appropriate collet or end mill holder sized for a 0.1875 inch shank. The spindle and all axes must be at a full stop before tool changes are made. Program the tool path using helical interpolation — standard G02 or G03 arc moves with a Z-axis feed component — per the machine control documentation. Verify runout at the tool holder before cutting, as excessive runout degrades thread form and accelerates tool wear.