Guhring 9039980063500 Spiral Flute Tap 1/4-20 Unc

Product Description

The GUHRING 9039980063500 is a spiral flute tap designed for blind hole threading in demanding materials including stainless steel. Built from powdered metal and coated with titanium nitride (TiN), it delivers extended tool life and heat resistance under production conditions. The 3-flute, right-hand design with a 40-degree helix angle efficiently evacuates chips upward out of the hole, making it well-suited for interrupted cuts and tough alloys. The modified bottoming chamfer allows threading close to the bottom of blind holes. This tap is installed by machinists and tool-and-die professionals working in shop or field machining environments.

This tap is intended for blind hole threading applications in stainless steel and other challenging materials where chip evacuation is critical. The 3B class of fit produces a standard tolerance thread suitable for most commercial fastener applications. With a right-hand thread and right-hand flute, it runs in conventional CNC and manual tapping operations. It belongs to GUHRING Series 3998, a line engineered for performance in difficult-to-machine materials.

Key Features

• 40-degree helix angle promotes upward chip evacuation in blind holes
• Powdered metal construction for increased wear resistance over standard HSS
• TiN coating reduces friction and extends tool life in stainless steel and hard alloys
• Modified bottoming chamfer for threading close to the bottom of blind holes
• 3B class of fit for standard commercial thread tolerance
• Coolant-through: No — suitable for conventional tapping setups

Compatibility

Designed for blind hole threading applications requiring a 1/4-20 UNC right-hand thread with a 3B class of fit, primarily in stainless steel workpieces.

Installation Notes

This tap is installed by machinists using CNC machining centers or manual tapping equipment. Always ensure the spindle is fully stopped and the workpiece is securely fixtured before tool changes. Use appropriate cutting fluid or tapping compound for stainless steel to prevent galling and extend tool life. Inspect the tap for wear regularly; a worn tap in stainless steel can seize and break in the hole.