Eagle Cutting Tool HT-440-B-I 4-40 Hss Bottom Tap

Product Description

The EAGLE CUTTING TOOL HT-440-B-I is a 4-40 high-speed steel (HSS) hand bottom tap designed for threading operations that require cutting threads to the bottom of a blind hole. This tap follows the bottom chamfer style, which provides minimal lead-in threads so material can be threaded as close to the base of the hole as possible. At 0.31 pounds, it is a lightweight hand tool suited for precision thread work in metal fabrication, maintenance, and repair applications. Machinists, tool-and-die workers, and maintenance technicians rely on this type of tap for fine-thread work in ferrous and non-ferrous materials.

This tap is used in applications requiring a 4-40 Unified National Coarse (UNC) thread profile, which is among the smallest standard machine screw thread sizes. It is well suited for threading small-diameter blind holes in sheet metal, machine housings, electronics enclosures, and other precision components where full thread depth is required. The hand-tap designation means it is intended for manual use with a tap wrench rather than powered tapping equipment.

Key Features

• Bottom chamfer style allows threading to the base of blind holes
• 4-40 thread size for fine, small-diameter machine screw applications
• High-speed steel construction provides hardness and wear resistance for threading metal
• Lightweight at 0.31 pounds for easy handling during hand-tap operations
• Minimum order quantity of 1 unit for single-piece procurement

Compatibility

Designed for use in standard 4-40 UNC hand-tapping applications where a bottom tap is required to achieve full thread depth in blind holes.

Installation Notes

This tap is installed by hand using a standard tap wrench. Ensure the workpiece is secured before beginning the tapping operation, and use appropriate cutting fluid to reduce friction and extend tap life. Reverse the tap periodically to break chips and prevent binding. Do not force the tap if resistance increases sharply, as small-diameter taps are susceptible to breakage under excessive torque.

Technical Specifications

• Thread Size: 4-40
• Tap Style: Bottom Chamfer (Hand Tap)
• Material: High-Speed Steel (HSS)
• Weight: 0.31 pounds

Standard Information

• Brand: EAGLE CUTTING TOOL
• Manufacturer Part Number: HT-440-B-I