Cleveland C58582 Spiral Flute Tap 3/8-16 Unc Bottoming Hss

Product Description

The CLEVELAND C58582 is a spiral flute bottoming tap designed for creating internal threads in blind holes. Built from high speed steel with a bright, uncoated finish, it cuts 3/8-16 UNC threads to a 3B class of fit with an H3 thread limit. The 52-degree helix angle and fast flute style evacuate chips efficiently in the reverse direction, which is the primary advantage of a spiral flute design over a straight flute tap. Overall length is 2.938 inches with a thread length of 0.75 inches. Licensed tradespeople and machining professionals use this tap in production and maintenance threading operations.

This tap is built for blind hole threading applications in alloy tool steel, carbon steel, and stainless steel. The bottoming chamfer allows threads to be cut as close to the bottom of a blind hole as possible, making it the right choice when full thread depth is required near the floor of a bored or drilled hole. It is commonly used in machine shops, manufacturing facilities, and industrial maintenance environments where a right-hand thread is required and chip control in a confined bore is critical.

Key Features

• Bottoming chamfer for maximum thread depth in blind holes
• 52-degree helix angle with fast flute style for efficient chip ejection
• 3/8-16 UNC thread form to 3B class of fit, H3 thread limit
• High speed steel construction rated for alloy tool steel, carbon steel, and stainless steel
• Right-hand flute and right-hand thread orientation
• Bright, uncoated finish — no added coating to alter tap geometry

Compatibility

Designed for use in Series 1093 and 1094 tooling applications. Suitable for blind hole threading operations in alloy tool steel, carbon steel, and stainless steel workpieces requiring a 3/8-16 UNC right-hand thread.

Installation Notes

This tap is installed by machinists and tool and die professionals using a tap wrench, tapping head, or CNC rigid tapping setup. Ensure the workpiece is securely fixtured and the pilot hole diameter matches the recommended tap drill size for 3/8-16 UNC before beginning. Apply appropriate cutting fluid for the workpiece material — stainless steel and alloy steels require adequate lubrication to prevent galling and premature tap wear. Do not force the tap if resistance increases suddenly; back off to clear chips before continuing.