Accupro 40083-01T Spiral Flute Tap 1/4-20 Unc Tin

Product Description

The ACCUPRO 40083-01T is a spiral flute tap designed for cutting 1/4-20 UNC internal threads in through-holes and blind-hole applications where chip evacuation is critical. Built from powdered metal with a titanium nitride (TiN) coating, this tap delivers increased wear resistance and longer tool life compared to standard high-speed steel options. The modified bottoming chamfer allows threading close to the bottom of a blind hole. With a 42-degree helix angle and fast flute style, it pulls chips up and out of the cut efficiently. Machinists, toolroom technicians, and CNC operators working in production environments are the primary users of this tap.

This tap is suited for threading ferrous and non-ferrous materials in both manual and CNC tapping operations. The 3B class of fit produces a standard tolerance internal thread appropriate for most general mechanical assemblies. The right-hand flute and right-hand thread configuration is the standard orientation for conventional tapping cycles. The H3 thread limit provides a slightly oversized thread to account for material springback, making it well suited for materials that tend to close up on the tap after cutting.

Key Features

• 1/4-20 UNC thread form, right-hand thread and right-hand flute
• 42-degree helix angle with fast flute style for efficient chip evacuation in blind holes
• Modified bottoming chamfer for threading close to the bottom of a blind hole
• Powdered metal construction with TiN coating for extended wear resistance
• H3 thread limit for 3B class of fit — suitable for standard mechanical assembly tolerances
• Overall length of 2.5 inches; weighs approximately 0.1 pounds

Compatibility

Designed as a direct-use spiral flute tap for 1/4-20 UNC tapping operations in standard tap holders, floating tap holders, and rigid tapping chucks compatible with the tap shank dimensions of a 1/4-20 size tap.

Installation Notes

This tap is installed and used by machinists and toolroom professionals. Secure the tap in an appropriate holder rated for the shank size before use, and ensure the spindle speed and feed rate are set per the machine tool manufacturer and tap manufacturer guidelines for the workpiece material. Always confirm the pre-drill hole diameter is correct for a 1/4-20 UNC tap before beginning the tapping cycle. Cutting fluid or tapping compound appropriate for the workpiece material should be applied to extend tool life and improve thread quality.