Hertel R837673 Extension Tap 5/8-11 Unc Hss

Product Description

The HERTEL R837673 is a 5/8-11 UNC extension tap designed for threading operations that require greater reach than a standard-length tap provides. Built from high speed steel (HSS) with a bright/uncoated finish, it delivers reliable performance across a range of ferrous and non-ferrous workpiece materials. The plug chamfer (7 to 10 threads) allows it to start easily in through-holes or deep holes where the lead can be gradually engaged. With an H3 thread limit and a 3B class of fit, this tap produces threads to standard tolerance for general-purpose fastener applications. Licensed machinists, tool-and-die makers, and maintenance mechanics typically run this tap in CNC or manual drill press setups.

This extension tap is suited for threading 5/8-11 UNC holes in production and maintenance environments where standard-length taps cannot reach the required depth. The reduced shank diameter of 0.48 inches allows it to pass through guide bushings or fixtures that would otherwise restrict a full-shank tool. With an overall length of 6 inches, it provides the reach needed for deep-hole work in fixtures, weldments, and structural components. It is appropriate for use in general manufacturing, fabrication shops, and industrial maintenance applications.

Key Features

• 5/8-11 UNC thread form with H3 thread limit for consistent 3B class of fit
• Plug chamfer (7-10 thread lead) for easy starting in through-holes and deep holes
• 6-inch overall length provides extended reach beyond standard tap lengths
• Reduced shank diameter of 0.48 inches for use with guide bushings and fixtures
• High speed steel construction for durability across ferrous and non-ferrous materials
• Bright/uncoated finish suitable for use with a wide range of cutting fluids

Compatibility

Designed as a replacement or additional tooling option for 5/8-11 UNC tapping applications requiring an extension-length tap with a reduced shank and plug chamfer. Compatible with standard tap holders and chucks accepting a 0.48-inch shank diameter.

Installation Notes

This tap is intended for use by qualified machinists and tooling professionals. Secure the workpiece firmly before tapping and use an appropriate cutting fluid for the workpiece material to reduce heat and extend tool life. Ensure the tap holder or chuck is properly aligned with the hole axis to prevent tap breakage. Do not force the tap if resistance increases suddenly — back off to clear chips before continuing.