Guhring 9039160028450 Spiral Point Tap 4-40 Unc Tin Hss-e

Product Description

The GUHRING 9039160028450 is a spiral point tap designed for cutting 4-40 UNC internal threads in through-hole applications. Built from HSS-E cobalt high-speed steel with a titanium nitride (TiN) coating, it delivers extended tool life when threading steel workpieces. The spiral point geometry pushes chips forward ahead of the cutting zone, keeping the flutes clear and reducing the risk of chip packing in production or repetitive threading operations. With an overall length of 1.882 inches, a thread length of 0.433 inches, and a 3-flute configuration, this tap is suited for machine tapping in CNC machining centers, drill presses, and tapping heads where consistent thread quality is required.

This tap is intended for through-hole threading in steel and similar ferrous materials at the 4-40 UNC thread standard. The 2B class of fit meets standard commercial tolerances used in fastener and precision assembly work. The H2/H3 thread limit keeps ground tolerances tight, making it appropriate for close-tolerance work in aerospace, electronics, and general fabrication. It is installed and operated by machinists and CNC operators working with small-diameter taps in production or job-shop environments. Coolant-through capability is not provided, so flood or mist coolant applied externally is recommended when tapping steel at higher feed rates.

Key Features

• Spiral point geometry pushes chips forward, suitable for through-hole threading
• HSS-E cobalt base material provides heat and wear resistance in steel applications
• TiN coating reduces friction and extends tool life compared to uncoated taps
• Plug chamfer (3-5 thread lead) allows controlled entry and is standard for machine tapping
• H2/H3 thread limit with 2B class of fit meets common commercial and precision assembly requirements
• Right-hand cut, 40 threads per inch, 3 flutes — compatible with standard tapping chucks and holders for No. 4 taps

Compatibility

Designed for through-hole threading of 4-40 UNC threads in steel workpieces. Series 3916 spiral point tap compatible with standard tapping chucks, floating tap holders, and CNC rigid tapping setups sized for No. 4 diameter taps.

Installation Notes

This tap is intended for use by machinists operating machine tapping equipment; hand tapping with this spiral point style is not the primary application. Ensure the workpiece is securely fixtured and the tap is properly aligned to avoid deflection on small-diameter threads. Apply appropriate cutting fluid or external coolant when threading steel to reduce heat buildup and extend tool life. Inspect the tap for chipping or wear before each use, as small-diameter taps are susceptible to breakage if run at incorrect speeds or feeds.