Eagle Cutting Tool HT-540-B-D 5-40 Hss Hand Bottom Tap

Product Description

The EAGLE CUTTING TOOL HT-540-B-D is a 5-40 thread hand bottom tap ground from high-speed steel (HSS) and manufactured in the USA. Bottom taps are designed to cut threads to the full depth of a blind hole, making them the right choice when thread engagement must extend as close to the bottom of the bore as possible. The short chamfer lead — typically 1 to 2 threads — requires a starter or plug tap to be used first in most blind-hole applications. At 0.04 pounds, this is a compact, precision-ground tap suited for threading in ferrous and non-ferrous metals, plastics, and similar materials.

The HT-540-B-D is used in machine shops, maintenance and repair operations, and tool rooms where 5-40 UNC threads are required in tight or shallow blind holes. The 5-40 designation means a No. 5 screw size with 40 threads per inch, a common fastener thread found in small instrumentation, electrical enclosures, and light mechanical assemblies. Hand-tap operation is performed with a standard tap wrench and is appropriate for low-volume threading where CNC or power tapping is not required.

Key Features

• 5-40 UNC thread form for small-diameter blind and through-hole applications
• Bottom chamfer geometry threads to the base of blind holes
• High-speed steel (HSS) construction provides hardness and wear resistance
• USA manufactured for consistent dimensional accuracy and thread quality
• Lightweight at 0.04 pounds — easy handling in tight workspaces

Compatibility

Designed as a hand bottom tap for use in any application requiring 5-40 UNC threads in blind or through holes. Use in sequence with a taper or plug tap when threading blind holes to full depth.

Installation Notes

Machinists and maintenance technicians use this tap with a standard tap wrench or T-handle. Always drill the correct tap drill size for 5-40 threads before tapping, and use appropriate cutting fluid for the material being threaded. In blind-hole applications, clear chips frequently to prevent tap breakage. Do not force the tap against the bottom of the hole — use the plug tap first to establish threads before switching to this bottom tap.

Technical Specifications

• Thread Size: 5-40 UNC
• Tap Type: Hand Bottom Tap
• Material: High-Speed Steel (HSS)
• Country of Origin: USA
• Weight: 0.04 pounds

Standard Information

• Brand: EAGLE CUTTING TOOL
• Manufacturer Part Number: HT-540-B-D