Hertel K008574AS Straight Flute Tap 5/8-18 Unf Hss

Product Description

The HERTEL K008574AS is a straight flute tap designed for cutting 5/8-18 UNF internal threads in a wide range of workpiece materials. Built from high speed steel with a bright/uncoated finish, this plug chamfer tap is suited for through-hole and blind-hole threading applications where chip flow is managed manually or with coolant flushing. The H3 thread limit provides the correct tolerance for standard 3B class fits. With 4 flutes and a right-hand thread direction, the tap delivers balanced cutting action and consistent thread form across production and maintenance threading work.

This tap is used in machining, maintenance, repair, and fabrication environments wherever 5/8-18 UNF threads are required. The plug chamfer style — typically 3 to 5 threads of taper — makes it the standard choice for starting threads in through holes or for following a taper tap in blind holes. It is appropriate for use in machine tapping setups or hand tapping operations performed by machinists, millwrights, and tool-and-die technicians.

Key Features

• 5/8-18 UNF thread form for fine-pitch unified national thread applications
• High speed steel construction for durability across ferrous and non-ferrous materials
• Plug chamfer geometry suitable for both through-hole and step-tapped blind-hole work
• H3 thread limit ensures proper 3B class fit tolerance
• 4 straight flutes for balanced cutting and chip clearance
• Right-hand thread direction, standard orientation for UNF fastener systems
• Bright/uncoated finish — compatible with a broad range of cutting fluids

Compatibility

Designed for cutting 5/8-18 UNF internal threads per unified thread standard specifications, compatible with standard tap holders and machine spindles sized for this tap shank diameter.

Installation Notes

This tap is installed by machinists and maintenance technicians using a standard tap wrench or machine tapping chuck rated for the shank size. Always apply appropriate cutting fluid for the workpiece material and ensure the tap is aligned perpendicular to the workpiece surface before engaging. De-energize any powered equipment before performing manual threading operations in situ. Do not force the tap if resistance increases unexpectedly — back off to clear chips and re-apply cutting fluid.