Guhring 9039190041660 Spiral Flute Tap 8-32 Unc

Product Description

The GUHRING 9039190041660 is a spiral flute tap designed for blind hole threading in metal workpieces. It cuts an 8-32 UNC right-hand internal thread with a modified bottoming chamfer, allowing threading close to the bottom of a blind bore. The tap is manufactured from cobalt high-speed steel with a bright, uncoated finish. Three fast-spiral flutes with a 40-degree helix angle evacuate chips efficiently out of the hole during cutting. The 2B class of fit produces a standard commercial thread tolerance. At 2.125 inches overall length with a 0.315-inch thread length, this tap is sized for typical machine or hand-tapping setups used by machinists and tool-and-die professionals.

This tap is suited for threading alloyed and unalloyed steel in blind-hole applications. The fast spiral flute geometry pulls chips upward and out of the hole, making it the correct choice when a plug tap or straight-flute tap would pack chips and risk breakage. Typical applications include machine components, fastener tapped holes in steel plate, and fixture fabrication where 8-32 threads are specified. It is appropriate for both CNC tapping operations and manual tapping with a reversible tapping head.

Key Features

• Modified bottoming chamfer for threading close to the bottom of blind holes
• 40-degree helix angle fast spiral flutes for reliable upward chip evacuation
• Cobalt high-speed steel construction for improved heat and wear resistance in steel alloys
• 2B class of fit for standard commercial thread tolerance on 8-32 UNC threads
• H3 and H4 thread limit range for controlled oversize tolerance
• Right-hand flute and right-hand thread — compatible with standard tapping attachments

Compatibility

Designed for blind hole threading of alloyed steel and unalloyed steel workpieces requiring an 8-32 UNC, 2B class of fit internal thread. Fits standard tap holders and tapping chucks sized for a 0.168-inch shank diameter with a 0.131-inch square drive.

Installation Notes

Install in a tapping chuck or tap wrench rated for the shank diameter before use. Ensure the workpiece is securely clamped and the pilot hole is drilled to the correct tap drill size for an 8-32 UNC thread before tapping. Apply an appropriate cutting fluid for steel to extend tap life and improve thread finish. Reverse the tap periodically when hand-tapping to break chips, and back out fully to clear the flutes before reaching the bottom of the blind hole.