Cleveland C55166 Hand Tap 8-32 Unc Plug Tin Hss

Product Description

The CLEVELAND C55166 is a straight-flute hand tap designed for cutting 8-32 UNC internal threads in metalworking applications. Built from high speed steel with a titanium nitride (TiN) coating, it offers increased surface hardness and lubricity compared to uncoated HSS taps. The plug chamfer provides 3 to 5 chamfered lead threads, making it suitable for both through-hole and blind-hole threading. With 4 flutes and a Class 2B thread fit at H2 thread limit, this tap produces threads within standard tolerance for most general-purpose fastener applications. Overall length is 2.125 inches with a thread length of 0.38 inches. Installed by machinists, tool and die technicians, and maintenance professionals.

The C55166 is suited for threading operations in cast iron, stainless steel, and steel workpieces. Its plug chamfer makes it a versatile first-choice tap for production and maintenance environments where both through-hole and blind-hole threading are common. The TiN coating extends tool life in abrasive materials and reduces the frequency of tap replacement in repetitive threading tasks. It is used in manual tapping with a tap wrench or T-handle, and can also be used in machine tapping at appropriate feed rates.

Key Features

• 8-32 UNC right-hand thread, Class 2B fit at H2 thread limit
• TiN coating over high speed steel for extended tool life and reduced friction
• Plug chamfer supports both through-hole and blind-hole threading
• 4-flute straight-flute design for chip clearance in ferrous materials
• Shank diameter of 0.168 inches with a 0.25-inch square drive end for standard tap wrenches
• No coolant-through requirement — suitable for hand and light machine tapping with cutting fluid applied externally

Compatibility

Designed for use in cast iron, stainless steel, and steel workpieces requiring 8-32 UNC internal threads to a Class 2B tolerance. Part of the CLEVELAND Series 1002TN.

Installation Notes

This tap is installed by machinists or maintenance technicians using a tap wrench or suitable machine holder. Ensure the workpiece is securely clamped and the pilot hole is drilled to the correct tap drill size for 8-32 UNC before tapping. Apply appropriate cutting fluid for the workpiece material, particularly when tapping stainless steel. Back the tap out periodically to break chips and clear flutes when threading blind holes.