Cleveland C55391 Spiral Point Tap 3/8-24 Unf Ticn Hss

Product Description

The CLEVELAND C55391 is a spiral point tap designed for through-hole threading in metalworking applications. Built from high speed steel with a TiCN (titanium carbonitride) finish, it cuts a 3/8-24 UNF right-hand thread with a plug chamfer and H3 thread limit. The 3-flute spiral point geometry pushes chips forward ahead of the cutting zone, making it well suited for through-hole work where chip evacuation is critical. With an overall length of 2.9375 inches and a thread length of 0.75 inches, it fits standard tap holders and drive equipment used in machine shop and field maintenance settings. Machinists, tool and die technicians, and maintenance mechanics are the typical users.

This tap is intended for through-hole threading operations in cast iron, stainless steel, and steel. The plug chamfer provides a gradual lead-in that distributes cutting forces across multiple threads, reducing tap breakage in harder materials. At 3/8-24 UNF, it is commonly used in precision fastener applications where fine-thread engagement is required, such as instrument mounting, hydraulic fittings, and structural assemblies. It is not rated for coolant-through use and is not an oversize tap.

Key Features

• Spiral point geometry pushes chips forward, optimized for through-hole threading
• TiCN coating improves wear resistance and extends tool life in ferrous materials
• High speed steel construction handles cast iron, stainless steel, and steel
• Plug chamfer (4-5 thread lead) suits production and general-purpose tapping
• H3 thread limit maintains consistent 2B class of fit tolerances
• Right-hand cut, 3 flutes, no coolant-through requirement

Compatibility

Designed for through-hole threading in cast iron, stainless steel, and steel workpieces. Fits standard tap holders sized for a 0.381-inch shank diameter. Part of the Cleveland Series 1011TICN product line.

Installation Notes

This tap should be installed and operated by a qualified machinist or maintenance mechanic familiar with tapping feeds, speeds, and tap holder alignment. Secure the workpiece fully before starting the threading operation and confirm the tap is running true to avoid breakage. Use an appropriate cutting fluid for the workpiece material, particularly when threading stainless steel. Follow shop safety procedures and applicable OSHA machine operation guidelines when using rotary cutting tools.