Cleveland C57622 Spiral Point Tap 1/4-28 Unc Hss

Product Description

The CLEVELAND C57622 is a spiral point plug tap designed for through-hole threading in metal workpieces. It cuts a 1/4-28 UNC right-hand thread and uses a 2-flute spiral point geometry to push chips forward ahead of the cutting zone, keeping the flutes clear during production runs. The tap is manufactured from high speed steel with an oxide finish for basic corrosion resistance and reduced galling. Overall length is 2.5 inches with a thread length of 1.0 inch, making it suited for standard-depth through-hole applications in machining, maintenance, and fabrication environments. Licensed machinists, millwrights, and maintenance mechanics are the primary users.

This tap is intended for through-hole threading in cast iron and steel workpieces. The plug chamfer provides a gradual lead-in that distributes cutting load across several threads at entry, which makes it practical for both hand tapping and machine tapping in drill press, CNC, or tapping arm setups. The 2B class of fit produces a standard commercial thread tolerance suitable for the majority of fastener and threaded insert applications at the 1/4-28 UNC specification.

Key Features

• Spiral point geometry pushes chips forward, reducing clogging in through-hole operations
• High speed steel construction provides durability across cast iron and steel materials
• Plug chamfer with 3-5 thread lead-in distributes cutting load at entry
• H3 thread limit holds consistent tolerance for 2B class of fit threads
• Oxide finish provides basic surface protection during storage and use
• Right-hand thread direction, 28 threads per inch, UNC standard

Compatibility

Designed for through-hole threading of cast iron and steel at the 1/4-28 UNC thread specification. Compatible with standard tap wrenches, tapping heads, and machine spindles accepting a 0.255-inch shank diameter.

Installation Notes

Secure the workpiece before tapping and ensure the through-hole pilot diameter is correct for a 1/4-28 UNC thread form prior to starting. Use an appropriate cutting fluid or tapping compound when threading steel or cast iron to extend tool life and improve thread finish. Apply consistent, controlled feed pressure whether hand tapping or machine tapping, and do not exceed the tap's rated material application range. Machinists should verify spindle alignment before powered tapping operations to avoid tap breakage.