Guhring 9039400041660 Thread Forming Tap 8-32 Unc

Product Description

The GUHRING 9039400041660 is a thread forming tap designed for creating internal 8-32 UNC threads without cutting chips, making it well-suited for applications where chip evacuation is a concern. Built from High-Speed Steel-E-CO (cobalt-enhanced HSS) and coated with Titanium Nitride (TiN), this tap offers improved wear resistance and tool life compared to uncoated HSS alternatives. It carries a 2BX class of fit with H5/H6 thread limits, delivering accurate thread geometry for reliable fastener engagement. The modified bottoming chamfer with 2-3 chamfered threads allows threading close to the bottom of blind holes. Machinists and tool-room technicians working in production or maintenance environments are the primary installers of this tap.

This tap is engineered for use in blind hole and through-hole threading operations across a range of workpiece materials including steel, stainless steel, cast iron, and non-ferrous metals — corresponding to material application codes P, M, K, and N. The Series 3940 design features 4 oil grooves and a 3xD flute-by-diameter ratio, supporting lubricant delivery to the forming zone during the tapping cycle. It is appropriate for use on CNC machining centers, drill presses, and manual tapping equipment where a tap wrench or holder accommodates the 0.1310-inch square drive size.

Key Features

• Thread forming (chipless) action reduces chip-related tap breakage in blind hole applications
• High-Speed Steel-E-CO (cobalt) construction increases hardness and heat resistance over standard HSS
• Titanium Nitride (TiN) coating extends tool life and reduces friction during the forming cycle
• Modified bottoming chamfer with 2-3 chamfered threads enables threading near the base of blind holes
• 4 oil grooves support consistent lubrication delivery to the forming area
• Compatible with steel, stainless steel, cast iron, and non-ferrous metals

Compatibility

Designed for blind hole and through-hole threading of 8-32 UNC threads in steel, stainless steel, cast iron, and non-ferrous metal workpieces. Suitable for use with standard tap holders and collet chucks that accommodate a 0.1680-inch shank diameter and 0.1310-inch square drive.

Installation Notes

Thread forming taps require appropriate tapping fluid or cutting oil matched to the workpiece material — do not run dry, particularly in stainless steel or cast iron. Ensure the spindle or tap wrench is properly aligned to the drilled hole before engagement to avoid cross-threading or tap breakage. For blind holes, verify the pre-drilled hole depth provides sufficient clearance beyond the required tapping depth. Follow the machine tool manufacturer guidelines and applicable shop safety procedures when securing the tap in the holder.