Cleveland C57131 Spiral Point Tap 1/4-20 Unc Bottoming Hss

Product Description

The CLEVELAND C57131 is a spiral point tap designed for threading blind holes in a range of common materials. It features a 1/4-20 UNC thread form with a bottoming chamfer, making it suited for threading to near the bottom of a blind hole where a standard or plug chamfer cannot reach. Manufactured from high speed steel with a bright finish and an H3 thread limit, this tap meets 3B class of fit standards. It carries a 2.5-inch overall length and a 0.63-inch thread length. Machinists, tool-and-die technicians, and maintenance trades rely on this style of tap for production and repair threading work.

This tap is intended for use in blind hole threading applications across soft to medium-hardness materials. Rated material applications include aluminum, copper alloys, low carbon steel, and magnesium. The bottoming chamfer style is selected when thread engagement is required close to the floor of a stopped hole. Right-hand cutting direction makes it compatible with standard spindle rotation. At 2 flutes, the spiral point geometry pushes chips forward ahead of the tap rather than packing them into the flute, reducing the risk of chip clogging in shorter blind holes.

Key Features

• Bottoming chamfer for threading close to the bottom of a blind hole
• Spiral point geometry drives chips forward to reduce clogging
• High speed steel construction for use in aluminum, copper alloys, low carbon steel, and magnesium
• H3 thread limit and 3B class of fit for consistent, controlled thread tolerance
• Bright finish with no coating for straightforward resharpening and inspection
• Right-hand thread direction for standard machine and hand tapping

Compatibility

Designed for blind hole threading in aluminum, copper alloys, low carbon steel, and magnesium. Compatible with standard 1/4-20 UNC tapping applications requiring a 3B class of fit and H3 thread limit. Part of the Cleveland Series 1012 tap line.

Installation Notes

Tapping operations should be performed by a qualified machinist or maintenance technician following standard shop safety practices. Ensure the workpiece is securely fixtured before starting. Use an appropriate cutting fluid or tapping compound for the specific material being threaded to extend tap life and improve thread quality. When used in a tapping machine or CNC spindle, confirm spindle speed and feed rate are set per the tap manufacturer guidelines for the material and tap size before engaging the tool.