Kennametal 6140637 Spiral Flute Tap 1/4-20 Cobalt Ticn

Product Description

The KENNAMETAL 6140637 is a spiral flute tap designed for cutting 1/4-20 right-hand internal threads in a range of ferrous and non-ferrous materials. The 3-flute, 45-degree helix geometry evacuates chips upward out of the hole — a critical advantage in blind-hole applications. The modified bottoming chamfer allows threading close to the bottom of a hole while still providing enough lead-in to start cleanly. Manufactured from cobalt high-speed steel and finished with a multi-layer TiCN/TiN coating, this tap is built for extended tool life in production tapping environments. Overall length is 2.5 inches with a thread length of 0.63 inches.

This tap is suited for threading blind holes in steel, stainless steel, cast iron, and aluminum and non-ferrous materials in both job-shop and production settings. The fast flute style and spiral geometry make it a practical choice for CNC machining centers and manual tapping operations where chip control and consistent thread quality are priorities. The H3 thread limit provides the correct tolerance class for standard 1/4-20 applications requiring a general-purpose fit.

Key Features

• 45-degree right-hand spiral flute for efficient upward chip evacuation in blind holes
• Modified bottoming chamfer for threading close to the bottom of blind holes
• Cobalt HSS construction for improved heat and wear resistance over standard HSS
• Multi-layer TiCN/TiN coating reduces friction and extends tool life in ferrous and non-ferrous materials
• H3 thread limit for standard general-purpose 1/4-20 tolerance requirements
• No coolant-through design — suitable for conventional flood or mist cooling setups

Compatibility

Rated for use in steel, stainless steel, cast iron, and aluminum and non-ferrous workpiece materials. Designed as an OEM-style replacement tap for standard 1/4-20 spiral flute tapping applications across compatible tap holders and tapping heads accepting a 0.255-inch shank diameter.

Installation Notes

Installation and use of this tap should be performed by a qualified machinist or tooling technician. Ensure the tap is secured in a properly sized tap holder or chuck rated for the shank diameter before operation. Always de-energize and lock out the machine spindle before changing tooling. Use appropriate cutting fluid or coolant for the workpiece material to prevent galling and premature tool wear.