Cleveland C55148 Hand Tap 7/8-9 Unc Tin Hss 4-flute

Product Description

The CLEVELAND C55148 is a 7/8-9 UNC straight flute hand tap designed for cutting internal threads in a range of ferrous and non-ferrous materials. Built from high speed steel and coated with titanium nitride (TiN), it delivers extended tool life and reduced friction during thread cutting. The plug chamfer style provides a balance between starting ease and thread engagement depth, making it suitable for both blind hole and through-hole threading operations. With 4 flutes and an H4 thread limit, the C55148 holds tight tolerances to a 3B class of fit. Machinists and toolroom technicians rely on this tap for production and maintenance threading work.

This tap is intended for use in manual tapping operations on materials including alloy steel, carbon steel, aluminum, and free-machining stainless steel. The plug chamfer makes it a versatile choice across both blind and through-hole applications. It fits standard tap wrenches sized for its 0.697-inch shank diameter. The 3/4-inch square drive is compatible with standard hand tap wrench chucks used in machine shop and maintenance environments.

Key Features

• TiN coating reduces friction and improves wear resistance for longer tool life
• H4 thread limit maintains consistent 3B class of fit tolerance
• Plug chamfer suits both blind hole and through-hole threading
• 4-flute straight flute geometry for reliable chip clearance in a range of materials
• High speed steel construction handles alloy steel, carbon steel, aluminum, and free-machining stainless steel
• Right-hand thread direction for standard tapping operations

Compatibility

Designed for use in standard hand tapping applications requiring a 7/8-9 UNC internal thread. Compatible with materials including alloy steel, carbon steel, aluminum, and free-machining stainless steel as specified by the manufacturer.

Installation Notes

Hand taps should be installed and operated by qualified machinists or toolroom technicians. Secure the workpiece fully before beginning threading, and apply cutting fluid appropriate for the material being tapped to reduce heat and tool wear. Back the tap off periodically during use to break chips and prevent binding. Do not exceed hand torque limits, as over-torquing a tap in a blind hole risks breakage and workpiece damage.