Eagle Cutting Tool HT-4375-20-B-I 7/16-20 Hss Bottom Tap

Product Description

The EAGLE CUTTING TOOL HT-4375-20-B-I is a 7/16-20 high-speed steel (HSS) hand bottom tap designed for cutting internal threads to the bottom of blind holes. Bottom taps feature a minimal chamfer lead — typically one to two threads — allowing the cutting edges to reach as close to the floor of a blind hole as possible. This tap is an import-grade tool suited for general-purpose threading in ferrous and non-ferrous metals. It is used by machinists, maintenance technicians, pipefitters, and tradespeople who need a fully threaded blind hole finished by hand or with a tap wrench.

This tap is appropriate for threading 7/16-20 UNF fine-pitch threads in a range of shop, field, and maintenance applications. Fine-pitch threads — 20 threads per inch — provide strong clamping force and are common in automotive, hydraulic, and precision mechanical assemblies. The bottom tap is typically the third tap in a three-tap sequence, following a taper tap and a plug tap to pre-form the thread before finishing to the hole bottom.

Key Features

• 7/16-20 UNF thread profile for fine-pitch internal threading applications
• High-speed steel (HSS) construction provides hardness and wear resistance across common metals
• Bottom chamfer design allows threading to the floor of blind holes
• Hand tap geometry compatible with standard tap wrenches and T-handle drivers
• Import-grade tool suitable for general maintenance and production threading tasks

Compatibility

Designed as a hand bottom tap for cutting 7/16-20 UNF internal threads in blind or through holes in ferrous and non-ferrous materials using a standard tap wrench.

Installation Notes

A licensed machinist or qualified tradesperson should ensure the workpiece is securely fixtured before tapping. Use appropriate cutting fluid for the material being threaded to extend tap life and improve thread finish. Back the tap off periodically to break chips and prevent binding in blind holes. Do not apply excessive torque — HSS taps can fracture if forced against an obstructed hole bottom.

Technical Specifications

• Thread Size: 7/16-20 UNF
• Tap Type: Hand Bottom Tap
• Material: High-Speed Steel (HSS)
• Weight: 0.31 pounds

Standard Information

• Brand: EAGLE CUTTING TOOL
• Manufacturer Part Number: HT-4375-20-B-I