Hertel K010323AS25 Thread Forming Tap 5-40 Unc Bottoming

Product Description

The HERTEL K010323AS25 is a bottoming-style thread forming tap designed for 5-40 UNC internal threading in blind holes. Manufactured from high-speed steel with a titanium nitride coating, it delivers increased surface hardness and extended tool life compared to uncoated alternatives. The bottoming chamfer — 1 to 2 threads — allows threading close to the bottom of blind holes where clearance is limited. With an overall length of 1.9375 inches and a thread length of 0.625 inches, it is a compact tooling solution suited for precision threading in small fastener applications. Class of fit is 2B and 3B with an H3 thread limit, and thread direction is right hand.

This tap is used in machining, tool and die, and maintenance repair operations where 5-40 UNC threads are required in blind-hole configurations. It is well suited for work in ferrous and non-ferrous metals where thread forming — rather than cutting — displaces material to produce stronger, smoother threads without generating chips. Machinists, tool room technicians, and maintenance professionals working with small-diameter fastener threads will find this tap appropriate for production and repair work in close-tolerance environments.

Key Features

• Bottoming chamfer (1-2 threads) for threading close to the bottom of blind holes
• High-speed steel construction for durability across a range of work materials
• Titanium nitride coating increases surface hardness and reduces wear
• H3 thread limit for consistent 2B and 3B class of fit results
• Right-hand thread direction, 5-40 UNC thread standard
• Chipless thread forming process produces stronger threads and eliminates chip clearance concerns in blind holes

Compatibility

Designed as an OEM-style replacement or direct tooling selection for applications requiring 5-40 UNC thread forming in blind holes at 2B or 3B class of fit.

Installation Notes

Thread forming taps are installed and driven by machinists or tool room technicians using a standard tap wrench, tapping head, or CNC machine with appropriate speed and feed settings for the work material. Before use, ensure the pilot hole diameter is correct for thread forming — forming taps require a slightly larger pilot hole than cutting taps. Secure the workpiece firmly and apply appropriate tapping fluid to extend tool life and maintain thread quality. Never reverse a thread forming tap under power without confirming the machine is set for proper reversal.