Cleveland C57628 3/8-16 Unc Spiral Point Tap Hss Oxide

Product Description

The CLEVELAND C57628 is a spiral point plug tap designed for through-hole threading in metalworking applications. Built from high speed steel with an oxide finish, it cuts a 3/8-16 UNC right-hand thread to a 2B class of fit and an H3 thread limit. The plug chamfer distributes cutting load across the lead threads, making it well suited for production tapping in both manual and machine setups. The spiral point geometry pushes chips forward ahead of the tap, keeping the flutes clear in through-hole work. Licensed machinists, toolroom technicians, and industrial maintenance trades use this tap for general-purpose threading in steel and cast iron.

This tap is intended for through-hole threading in materials including cast iron and steel. With a 3/8-16 UNC thread form, it fits standard fractional fastener applications across general manufacturing, maintenance, and repair environments. The 3-flute spiral point design is most effective in through-hole configurations where chips can exit ahead of the cutting action. It is not designed for blind-hole applications where chip evacuation is restricted.

Key Features

• 3/8-16 UNC thread form, right-hand cut, 2B class of fit
• H3 thread limit for consistent fit across production runs
• High speed steel construction for durability in steel and cast iron
• Oxide finish provides basic lubricity and corrosion resistance
• Spiral point geometry pushes chips forward for clean through-hole threading
• Plug chamfer style for standard entry in open or through-hole work

Compatibility

Designed as a standard spiral point plug tap for through-hole threading of 3/8-16 UNC threads in cast iron and steel workpieces. Compatible with manual tap handles and machine tapping setups that accept straight shank taps of the corresponding shank diameter.

Installation Notes

Tapping should be performed by a qualified machinist or maintenance technician using proper tapping fluid or cutting oil appropriate for the workpiece material. Ensure the tap is properly aligned with the drilled hole before applying torque to prevent tap breakage or thread damage. A correctly sized tap drill should be used prior to tapping; consult a standard tap drill chart for the 3/8-16 UNC thread form. Follow applicable shop safety procedures and machine guarding requirements when using power tapping equipment.