Value Collection JY4848131 Straight Flute Tap 7/8-18 Uns

Product Description

The VALUE COLLECTION JY4848131 is a straight flute bottoming tap designed to cut internal threads in pre-drilled holes where full thread depth is required close to the bottom of a blind bore. Manufactured from high-speed steel with a bright, uncoated finish, this tap produces 7/8-18 UNS right-hand threads and features 4 flutes for chip clearance during cutting. With an overall length of 4-11/16 inches and an H3 thread limit, it is suited for precision threading operations in a machine shop or field maintenance environment. Machinists, toolmakers, and maintenance technicians are the primary installers.

This bottoming tap is intended for use when a chamfer tap or plug tap has already started the thread and the final threading pass must reach the bottom of a blind hole. The 7/8-18 UNS thread specification is a unified national special form commonly found in hydraulic fittings, aerospace components, and specialty mechanical assemblies. It is appropriate for use in both manual tapping handles and low-speed machine tapping setups where controlled torque is applied. The H3 tolerance class supports close-tolerance thread fits typical in precision assemblies.

Key Features

• Bottoming chamfer allows threading to the full depth of a blind hole
• 7/8-18 UNS thread form for specialty and hydraulic fitting applications
• 4-flute design provides chip clearance and cutting stability
• High-speed steel construction offers durability across a range of workpiece materials
• H3 thread limit for close-tolerance, precision thread fits
• Right-hand thread direction, standard for the majority of threading applications

Compatibility

Designed as an OEM-style replacement or standard tooling option for machines and hand tapping applications requiring 7/8-18 UNS internal threads in blind-hole configurations.

Installation Notes

This tap should be used only after a taper or plug tap has established the thread lead in the hole. Secure the workpiece firmly before tapping and apply cutting fluid appropriate to the workpiece material to reduce heat and extend tool life. Use a calibrated torque handle or controlled-speed machine tapping attachment to avoid tap breakage, particularly near the bottom of a blind bore. Follow applicable shop safety practices and machine guarding requirements during operation.