Cleveland C58565 Spiral Flute Tap 1/4-28 Unf Bottoming Hss

Product Description

The CLEVELAND C58565 is a spiral flute tap designed for bottoming thread applications in blind holes. Built from high speed steel with a bright/uncoated finish, this tap cuts 1/4-28 UNF right-hand threads to a 3B class of fit. The 52-degree helix angle and fast flute style pull chips up and out of the hole during cutting, reducing the risk of chip packing in blind holes. With a thread length of 0.63 inches and an overall length of 2.5 inches, the C58565 suits production and maintenance tapping operations where a bottoming chamfer is required to thread close to the bottom of a blind bore.

This tap is suited for threading blind holes in alloy steel, carbon steel, and stainless steel workpieces. The bottoming chamfer allows threading to within one or two threads of the hole bottom, making it appropriate for applications where full thread depth in a blind hole is required. It carries an H3 thread limit, which is appropriate for use with standard cutting fluids and general-purpose tapping on manual machines, CNC machines, and tapping heads in light-to-medium production environments.

Key Features

• Bottoming chamfer for threading close to the bottom of blind holes
• 52-degree helix angle with fast flute style for efficient chip evacuation
• High speed steel construction for durability across alloy steel, carbon steel, and stainless steel
• H3 thread limit for consistent 3B class of fit
• Right-hand flute and right-hand thread configuration
• Bright/uncoated finish compatible with standard cutting oils and fluids

Compatibility

Designed for use in blind hole threading applications requiring a 1/4-28 UNF thread form in alloy steel, carbon steel, and stainless steel. Part of the CLEVELAND Series 1093 and 1094 tap family.

Installation Notes

A qualified machinist or tooling technician should install and operate taps using a properly sized tap wrench, tapping head, or CNC rigid tapping cycle. Ensure the workpiece is securely fixtured and the pilot hole is drilled to the correct tap drill diameter before threading. Apply a suitable cutting fluid or tapping compound for the work material to extend tool life and improve thread quality. Never force a tap that has stopped advancing, as breakage in a blind hole is difficult to remedy.