Cleveland C57151 Spiral Point Tap 5/16-18 Unc Hss

Product Description

The CLEVELAND C57151 is a spiral point plug tap designed for through-hole threading in ferrous and non-ferrous materials. Built from high-speed steel (HSS) with a bright, uncoated finish, it cuts a 5/16-18 UNC thread to a 3B class of fit with an H3 thread limit. The two-flute, spiral point geometry pushes chips forward ahead of the cut, making it well suited for through-hole applications where chip evacuation matters. Overall length is 2.719 inches with a thread length of 0.690 inches. Licensed machinists, tool-and-die technicians, and maintenance professionals use this tap for production and repair work on steel, aluminum, and alloy components.

The C57151 is used in through-hole tapping operations across general manufacturing, MRO maintenance, and fabrication environments. It is appropriate for right-hand threading in alloy steel, carbon steel, and aluminum workpieces. The plug chamfer distributes cutting load across several leading threads, making it a standard choice for both hand tapping and machine tapping setups where a starting chamfer is acceptable. It is sold individually and is part of Cleveland Series 1011.

Key Features

• Spiral point geometry pushes chips forward for efficient through-hole threading
• 5/16-18 UNC thread form with H3 thread limit and 3B class of fit
• High-speed steel construction for durability across steel and aluminum materials
• Plug chamfer for balanced cutting load and versatile machine or hand use
• Bright, uncoated finish — no coating buildup to affect thread tolerance
• Right-hand thread direction, Series 1011

Compatibility

Designed for through-hole tapping of alloy steel, carbon steel, and aluminum. Compatible with standard 5/16-18 UNC tapping applications in machining centers, drill presses, and hand tapping fixtures that accept a 0.318-inch shank diameter.

Installation Notes

This tap is installed and used by machinists, maintenance technicians, and tool-and-die professionals. Ensure the workpiece is securely fixtured and the tap is properly aligned before beginning the cut. Use an appropriate tapping fluid or cutting oil for the workpiece material to extend tool life and improve thread quality. For machine tapping, verify spindle speed and feed rate are set for the material and tap size before engaging the cut.