Accupro T1630374 Spiral Point Tap M8 X 1 Plug Hss

Product Description

The ACCUPRO T1630374 is a spiral point plug tap designed for threading M8 x 1 holes in a wide range of machining applications. Built from 3% vanadium high speed steel with an oxide finish, it delivers improved wear resistance and lubricity compared to standard HSS taps. The three-flute spiral point design pushes chips forward ahead of the cutting zone, making it well suited for through-hole tapping. With an overall length of 69 millimeters and a thread length of 22 millimeters, this tap fits standard tap holders and is sized for use on CNC machining centers, drill presses, and manual tapping operations. The D4 thread limit provides the tolerance control required for precision threaded fastener fits.

This tap is optimized for use in stainless steel, a material that demands sharper cutting geometry and higher alloy tooling due to its work-hardening characteristics. The plug chamfer — typically 3 to 5 threads of lead — allows the tap to self-start in a pre-drilled hole and is the standard choice for most through-hole production tapping. It is appropriate for both horizontal and vertical tapping setups in job shop, production, and maintenance environments. Right-hand thread direction matches standard M8 x 1 fastener specifications.

Key Features

• M8 x 1 thread size, right-hand direction
• 3% vanadium HSS construction for extended tool life in stainless steel
• Oxide finish improves lubricity and reduces galling
• Spiral point geometry pushes chips forward for clean through-hole threading
• D4 thread limit for controlled tolerance fits
• Plug chamfer for easy starting in pre-drilled through holes

Compatibility

Rated for use in stainless steel workpieces. Fits standard M8 tap holders and collet chucks compatible with an 8.08 millimeter shank diameter.

Installation Notes

This tap should be installed by a machinist or tool-and-die professional using a properly sized tap holder or floating tap collet. Ensure the workpiece is securely fixtured and the pre-drilled hole meets the correct tap drill diameter for M8 x 1 before starting. Apply cutting fluid rated for stainless steel to reduce heat buildup and extend tap life. Do not reverse the tap under power without a reversing tap head or CNC canned cycle to avoid breakage.