Hertel K008364AS Spiral Point Tap 1/4-28 Unf Hss

Product Description

The HERTEL K008364AS is a spiral point tap designed to cut right-hand internal threads in a 1/4-28 UNF thread form. It features two flutes and a plug chamfer, making it suited for through-hole tapping applications where chips are pushed ahead of the tap and cleared from the cutting zone. Built from high-speed steel with a bright uncoated finish, this tap delivers consistent thread quality to a 3B class of fit and an H3 thread limit. Licensed machinists, maintenance technicians, and toolroom professionals use this tap in both production and repair settings.

This tap is used in through-hole threading operations on materials where high-speed steel performs reliably, including mild steel, aluminum, and similar metals. The plug chamfer provides a gradual lead-in over several threads, reducing entry force and helping maintain thread accuracy. It is appropriate for use in manual tapping, drill press setups, and CNC tapping cycles with appropriate tapping fluid or cutting oil. Typical applications include fastener hole preparation in mechanical assemblies, fixtures, and equipment repair.

Key Features

• 1/4-28 UNF thread form for fine-pitch fastener applications
• Plug chamfer provides gradual lead-in suited for through-hole tapping
• Two-flute design pushes chips forward and clears them from the cut
• H3 thread limit holds consistent tolerance for 3B class of fit
• High-speed steel construction offers durability across common workpiece materials
• Bright uncoated finish allows easy visual inspection of cutting edge condition

Compatibility

Designed as a standard spiral point tap for right-hand 1/4-28 UNF through-hole threading operations in compatible toolholders and tap wrenches that accept straight-shank taps of this size class.

Installation Notes

Tapping should be performed by a qualified machinist or maintenance technician familiar with thread-cutting practices. Secure the workpiece firmly before starting and use an appropriate cutting fluid or tapping oil to reduce heat and extend tool life. Ensure the tap is aligned perpendicular to the workpiece surface before applying torque. Do not force a tap that has stopped turning, as this may indicate chip packing or tool binding that can result in breakage.