Cleveland C57630 Spiral Point Tap 3/8-24 Unc Hss

Product Description

The CLEVELAND C57630 is a spiral point tap designed for through-hole threading in ferrous materials including cast iron and steel. It carries a 3/8-24 UNC thread form with a plug chamfer and three flutes, driving chips forward ahead of the cut to keep the flute clear during the threading operation. Built from high speed steel with an oxide finish for basic corrosion resistance, this tap holds an H3 thread limit and a Class 2B fit tolerance. Overall length is 2.9375 inches with a thread length of 1.25 inches, making it suited to standard-depth through-hole applications in production and maintenance environments. Licensed machinists and trade professionals are the primary users.

This tap is built for through-hole threading applications where chip ejection is critical to thread quality. It performs well in cast iron and steel workpieces commonly encountered in mechanical, HVAC equipment fabrication, plumbing manifold work, and general industrial maintenance. The plug chamfer distributes the cutting load across several leading threads, reducing tool stress at entry. The right-hand thread direction is standard for the majority of fastener applications in these trades. The 1011BO series designation is the Cleveland product line identifier for this configuration.

Key Features

• Spiral point geometry drives chips forward for clean through-hole threading without clogging
• Plug chamfer entry distributes cutting load and eases tap start
• High speed steel construction handles cast iron and steel without specialized coatings
• H3 thread limit with Class 2B fit for reliable mating with standard UNC fasteners
• Oxide finish provides basic rust resistance during storage and use
• Right-hand, no coolant-through design suits general-purpose machine or hand tapping

Compatibility

Designed for through-hole threading of 3/8-24 UNC threads in cast iron and steel workpieces. Compatible with standard tap holders and chucks accepting a 0.381-inch shank diameter.

Installation Notes

This tap is installed by licensed machinists or qualified tradespeople using a tap wrench, drill press, or CNC tapping cycle. Secure the workpiece fully before tapping and ensure the pilot hole diameter matches the recommended tap drill size for 3/8-24 UNC threads. Apply cutting fluid appropriate for the base material to extend tool life and improve thread finish. Reverse the tap periodically when hand-tapping to break chips, even though the spiral point design ejects chips forward in through-hole operations.