Accupro T1604602B Spiral Flute Tap 9/16-12 3 Flute 2B

Product Description

The ACCUPRO T1604602B is a spiral flute tap designed for threading 9/16-12 UNC holes in production and maintenance machining operations. Built from 3% Vanadium High Speed Steel with an oxide finish, it provides enhanced wear resistance and chip evacuation in through-hole and modified bottoming applications. The fast flute design with a 40-degree helix angle pulls chips up and out of the hole efficiently, reducing the risk of re-cutting and tap breakage. With a 2B class of fit, it produces standard commercial-tolerance threads suitable for most fastener applications. Overall length is 3.5938 inches. This tap is intended for use by machinists, tool and die makers, and maintenance professionals working with ferrous and non-ferrous materials.

This tap is suited for both job shop and production environments where 9/16-12 UNC internal threads are required. The modified bottoming chamfer allows threading closer to the bottom of a blind hole than a standard taper tap while retaining more lead than a true bottoming chamfer, making it a practical general-purpose choice for moderate-depth blind holes. Thread length is 22.00 mm. The right-hand flute and right-hand thread configuration are standard for conventional threading operations. Coolant-through capability is not available on this tap, so flood or brush-applied cutting fluid should be used at the machine for tool life.

Key Features

• 9/16-12 UNC thread size with 2B class of fit for standard commercial tolerances
• 3% Vanadium HSS construction for improved hardness and wear resistance over standard M2 HSS
• 40-degree helix angle fast flute for aggressive chip evacuation in blind holes
• Modified bottoming chamfer for threading close to hole bottom without full bottoming tap limitations
• Oxide finish reduces friction and provides light corrosion resistance during storage and use
• Right-hand thread, right-hand flute — compatible with standard CNC and manual tapping setups

Compatibility

Designed as an OEM-style replacement or direct-use tap for any 9/16-12 UNC tapping application requiring a 3-flute spiral flute geometry and 2B thread tolerance. Verify machine spindle and tap holder compatibility with a 10.90 mm shank diameter before installation.

Installation Notes

Installation and use should be performed by a qualified machinist familiar with speeds, feeds, and cutting fluid requirements for the workpiece material. Power down and lock out the machine before loading or removing the tap from the holder. Use a properly sized tap holder or floating collet to prevent tap breakage from misalignment. Always apply cutting fluid appropriate to the workpiece material — dry tapping is not recommended with HSS taps.