Regal Cutting Tools 017855AS Straight Flute Tap 1-1/4-8 Uns

Product Description

The REGAL CUTTING TOOLS 017855AS is a straight flute tap designed for cutting 1-1/4-8 UNS internal threads in a variety of metalworking applications. Built from high-speed steel (HSS) with a bright/uncoated finish, this tap offers reliable performance in threading operations where coolant-through capability is not required. It features a bottoming chamfer for threading close to the bottom of blind holes, 4 flutes for efficient chip clearance, and a right-hand thread direction. With an overall length of 5.75 inches and a thread length of 2.5625 inches, it is sized for use in production and maintenance machining environments and is installed by machinists and toolroom professionals.

This tap is suited for threading operations in ferrous and non-ferrous materials where a UNS 1-1/4-8 thread form is required. The bottoming chamfer makes it appropriate for blind-hole applications where full thread depth near the hole bottom is necessary. It is commonly used in job shops, maintenance facilities, and manufacturing environments. The H5 thread limit designation ensures consistent fit with standard tolerance class specifications for this thread size.

Key Features

• Bottoming chamfer allows threading to the bottom of blind holes
• 4-flute design promotes chip evacuation during threading
• High-speed steel construction provides durability across a range of workpiece materials
• Bright/uncoated finish suitable for general-purpose threading applications
• H5 thread limit for controlled tolerance fit
• Right-hand thread direction, standard for most threading operations

Compatibility

Designed as a standard straight flute tap for cutting 1-1/4-8 UNS right-hand internal threads in applications requiring an H5 thread limit and bottoming chamfer geometry.

Installation Notes

This tap is installed by machinists using a tap wrench, tapping head, or compatible machine spindle. Ensure the workpiece is securely fixtured and the pilot hole is drilled to the correct tap drill diameter for a 1-1/4-8 UNS thread before tapping. Apply appropriate cutting fluid for the workpiece material to extend tap life and improve thread quality. Do not force the tap if resistance increases suddenly, as this may indicate chip packing or misalignment.