Accupro T1604723 Spiral Flute Tap 3/4-16 Modified Bottoming

Product Description

The ACCUPRO T1604723 is a spiral flute tap designed for cutting 3/4-16 UNF internal threads with a modified bottoming chamfer. Built from 3% vanadium high-speed steel with an oxide coating, this tap handles demanding applications including stainless steel. The spiral flute design — running at a 40-degree helix angle with a fast flute style — evacuates chips up and out of the hole, reducing the risk of packing in blind bores. The H3 thread limit and 3B class of fit make it well-suited for standard tolerance threaded assemblies. Overall length is 4.25 inches with a thread length of 25 millimeters. Licensed machinists and toolmakers are the primary users of this tap.

This tap is intended for production and repair threading in ferrous and stainless steel workpieces where a modified bottoming chamfer is required to thread close to the bottom of a blind hole. Right-hand spiral flute geometry makes it appropriate for CNC machining centers and manual lathes running right-hand feed. The tap does not support coolant-through operation, so flood or external coolant delivery is required when threading stainless steel or other difficult materials.

Key Features

• 3/4-16 UNF thread form with 3B class of fit and H3 thread limit for standard tolerance control
• Modified bottoming chamfer allows threading to within a few threads of the bottom of a blind hole
• 40-degree right-hand spiral flute evacuates chips upward, reducing clogging in blind bore applications
• 3% vanadium high-speed steel construction provides wear resistance and edge retention in stainless steel
• Oxide coating reduces friction and provides light corrosion protection during storage and use
• Right-hand thread direction compatible with standard CNC and manual tapping setups

Compatibility

Designed as a direct-use spiral flute tap for 3/4-16 UNF threaded holes in stainless steel and similar ferrous materials. Compatible with standard tapping chucks and holders sized for a 14.99 millimeter shank diameter.

Installation Notes

Installation should be performed by qualified machinists following standard threading procedures. Secure the workpiece fully before tapping and ensure the spindle or tap wrench is properly aligned to prevent tap breakage. Apply appropriate cutting fluid rated for stainless steel when threading difficult materials. Do not use coolant-through holders, as this tap does not support internal coolant delivery.