Cleveland C55390 Spiral Point Tap 3/8-16 Unf Ticn Hss

Product Description

The CLEVELAND C55390 is a spiral point plug tap designed for through-hole threading in metalworking and machining applications. Built from high speed steel with a titanium carbonitride (TiCN) coating, it delivers improved wear resistance and surface hardness compared to uncoated tooling. The 3/8-16 UNF thread form with a 3-flute spiral point geometry pushes chips forward ahead of the cutting action, making it well suited for tapping in through-hole configurations. Overall length is 2.94 inches with a 0.75-inch thread length. The H3 thread limit provides the correct tolerance for Class 2B fit requirements in general-purpose fastener applications. This tap is installed by machinists, toolmakers, and maintenance technicians working with ferrous metals.

The C55390 is rated for use in cast iron, stainless steel, and steel. The plug chamfer distributes cutting load across several leading threads, reducing the force required to start the tap and improving thread quality at the entry. Right-hand cutting direction matches standard right-hand thread fastener requirements. The TiCN finish extends tool life in abrasive and hard materials compared to bright or TiN-coated alternatives. This tap is part of the CLEVELAND Series 1011TICN product line and is sold individually in single-unit packaging.

Key Features

• 3/8-16 UNF thread form with H3 thread limit for Class 2B fit
• TiCN coating increases surface hardness and wear resistance for longer tool life in ferrous materials
• Spiral point geometry pushes chips forward, optimized for through-hole tapping
• Plug chamfer distributes cutting load over several threads for easier tap entry
• High speed steel construction handles cast iron, stainless steel, and steel applications
• Right-hand cut, no coolant-through requirement, not oversize

Compatibility

Rated for through-hole threading in cast iron, stainless steel, and steel workpieces. Designed for use with standard tap holders and machine spindles accepting the 0.381-inch shank diameter.

Installation Notes

This tap is installed by machinists and maintenance technicians using a tapping machine, CNC machining center, or hand tap wrench. Ensure the workpiece is securely fixtured and the tap is aligned perpendicular to the drilled hole before engagement. Apply a suitable cutting fluid for the work material to improve finish quality and extend tool life. Inspect the tap for wear or chipping before each use and replace when cutting torque increases noticeably or thread quality degrades.