Cleveland C55374 Spiral Point Tap 4-40 Unf Hss Ticn

Product Description

The CLEVELAND C55374 is a spiral point plug tap designed for through-hole threading in ferrous metals. It cuts a 4-40 UNF thread profile with a 2-flute, right-hand spiral point geometry that pushes chips forward ahead of the cutting zone, reducing the risk of chip packing in blind-adjacent through-hole applications. The tap is manufactured from High Speed Steel with a TiCN (Titanium Carbonitride) coating, which improves surface hardness and lubricity for extended tool life. The H2 thread limit holds close dimensional tolerances for a Class 2B fit. Overall length is 1.875 inches with a 0.3100-inch thread length.

This tap is suited for threading 4-40 UNF holes in cast iron, stainless steel, and carbon steel workpieces. It is a practical choice for machine shops, maintenance technicians, and field service professionals working with small-diameter fastener holes in industrial equipment, electrical enclosures, and instrumentation assemblies. The plug chamfer style makes it appropriate for through-hole applications where the tap can pass fully through the material.

Key Features

• 4-40 UNF thread profile with 40 threads per inch
• TiCN coating increases surface hardness and reduces friction for longer tool life
• Spiral point geometry pushes chips forward, ideal for through-hole threading
• H2 thread limit for Class 2B fit tolerance
• Right-hand cut, plug chamfer style
• Rated for use in cast iron, stainless steel, and steel

Compatibility

Designed for through-hole threading in cast iron, stainless steel, and steel. Fits standard tap holders and tapping heads accepting a 0.1410-inch shank diameter.

Installation Notes

This tap is intended for use by machinists and maintenance technicians using manual tap wrenches or machine tapping setups. Secure the workpiece before tapping and ensure the pilot hole diameter is correct for a 4-40 thread before starting. Apply appropriate cutting fluid for the material being threaded, particularly when working in stainless steel. Coolant-through operation is not supported on this tap.