Guhring 9008780381000 Spiral Point Tap 1-1/2-6 Unc

Product Description

The GUHRING 9008780381000 is an HSS-E cobalt spiral point tap designed for through-hole threading in steel and similar ferrous materials. Manufactured to a 1-1/2-6 UNC thread form with a 2B class of fit, this tap produces right-hand internal threads with consistent dimensional accuracy. The spiral point geometry pushes chips ahead of the cut rather than packing them in the flutes, making it well suited for through-hole applications where chip evacuation is a priority. With four flutes, an H7/H8 thread limit, and a bright uncoated finish, this tap delivers reliable performance in production and maintenance threading operations.

This tap is intended for through-hole threading applications in steel, and is appropriate for use in machine tapping operations on CNC machining centers, knee mills, and manual drill presses with tapping attachments. The plug chamfer provides a 3-5 thread lead-in, making it the standard choice for through-hole work where the tap can pass completely through the workpiece. It is commonly specified by machinists and toolroom professionals working with large-diameter threaded connections in industrial, structural, and heavy equipment contexts.

Key Features

• 1-1/2-6 UNC thread form with 2B class of fit for standard tolerance internal threads
• Spiral point geometry pushes chips forward, optimizing performance in through-hole threading
• HSS-E cobalt construction provides elevated heat and wear resistance compared to standard HSS
• Plug chamfer (3-5 thread lead) suited for through-hole applications
• H7/H8 thread limit ensures consistent fit across production runs
• Right-hand cut, no coolant-through, bright uncoated finish

Compatibility

Designed for through-hole threading of steel workpieces requiring a 1-1/2-6 UNC right-hand internal thread. Part of GUHRING Series 878.

Installation Notes

This tap should be installed in a machine tapping holder or a dedicated tap chuck rated for the required torque at this diameter - hand tapping at 1-1/2 inch diameter is not recommended for production use. Ensure the workpiece is securely fixtured and the spindle is properly aligned to avoid tap breakage. Apply an appropriate cutting fluid or tapping compound for steel before beginning the threading cycle. Always power down and de-energize the machine before changing tooling or inspecting threaded holes.