Guhring 9019790021840 Straight Flute Tap 2-56 Unc

Product Description

The GUHRING 9019790021840 is a straight flute tap designed for cutting internal threads in blind holes and through-holes. It features a 2-56 UNC thread form with 3 flutes and a modified bottoming chamfer, allowing thread cutting close to the bottom of a blind hole. Manufactured from cobalt high-speed steel with an oxide finish, this tap delivers added heat and wear resistance compared to standard HSS tooling. The right-hand thread direction and 2B class of fit make it a standard choice for general-purpose threaded fastener applications in precision machining and fabrication work. Overall length is 45 millimeters with a shank diameter of 2.80 millimeters.

This tap is suited for threading operations in gray cast iron, malleable iron, and spheroidal iron workpieces. The modified bottoming chamfer allows the tap to start cleanly and thread deeper into blind holes than a standard taper or plug chamfer would permit. It is appropriate for use in CNC machining centers, drill presses, and manual tapping applications where a fine 2-56 thread pitch is required. Machinists, toolmakers, and production operators in precision manufacturing environments are the typical users of this tool.

Key Features

• 2-56 UNC thread form with 56 threads per inch and 2B class of fit
• Modified bottoming chamfer for threading close to the bottom of blind holes
• 3-flute straight flute geometry for chip clearance in short-chipping materials
• Cobalt HSS construction with oxide finish for improved heat and wear resistance
• H2/H3 thread limit for consistent tolerance control
• No coolant-through requirement; compatible with standard cutting fluids applied externally

Compatibility

Designed for blind hole threading and through-hole threading in gray cast iron, malleable iron, and spheroidal iron. Part of the GUHRING Series 1979 straight flute tap line.

Installation Notes

This tap should be installed and operated by a qualified machinist or toolmaker familiar with tapping procedures and speeds for cobalt HSS tooling. Secure the workpiece fully before beginning any threading operation and use an appropriate cutting fluid for ferrous materials to extend tool life. Ensure the tap is properly aligned with the drilled pilot hole to prevent tap breakage, particularly at this small diameter. Follow the machine manufacturer and tooling guidelines for spindle speed and feed rate when power tapping.