Cleveland C55389 Spiral Point Tap 5/16-24 Unf Ticn Hss

Product Description

The CLEVELAND C55389 is a spiral point plug tap designed for through-hole threading in ferrous and stainless materials. Built from high speed steel (HSS) with a titanium carbonitride (TiCN) coating, it delivers harder wear resistance and extended tool life compared to uncoated alternatives. The plug chamfer configuration — typically 3 to 5 lead threads — eases entry and makes it practical for through-hole applications where chip evacuation is assisted by the spiral point geometry pushing chips forward ahead of the cut. Sized at 5/16-24 UNF with a right-hand thread direction and H4 thread limit, this tap suits precision threading work in automotive, mechanical, and industrial maintenance settings. Licensed machinists and maintenance technicians are the primary users.

The C55389 is suited for through-hole threading operations in cast iron, stainless steel, and steel. The TiCN finish supports higher cutting speeds and reduces built-up edge in tougher alloys. With a thread length of 0.69 inches (11/16 inches), a shank diameter of 0.318 inches, and a neck length of 0.45 inches (29/64 inches), it fits standard tap holders and CNC tapping chucks designed for this shank size. It is particularly well suited to production environments where tool life and consistent thread class 2B fit are priorities.

Key Features

• 5/16-24 UNF right-hand thread, class 2B fit with H4 thread limit for consistent tolerance
• TiCN coating increases surface hardness and wear resistance over uncoated HSS taps
• Spiral point geometry pushes chips forward — optimized for through-hole threading, not blind holes
• 3-flute plug chamfer provides stable entry and suits a wide range of machine tapping applications
• Rated for cast iron, stainless steel, and steel material applications
• No coolant-through feature — use external flood or mist coolant as appropriate

Compatibility

Designed as an OEM-style cutting tool replacement for 5/16-24 UNF through-hole tapping operations; compatible with standard tap holders and machine tapping chucks accepting a 0.318-inch shank diameter. Series 1011TICN from CLEVELAND.

Installation Notes

Machining operations with this tap should be performed by qualified machinists or maintenance technicians familiar with tapping feeds, speeds, and cutting fluid requirements for the workpiece material. Secure the workpiece fully and confirm spindle alignment before tapping to avoid tap breakage. Use appropriate cutting fluid or coolant for the material being tapped — stainless steel in particular benefits from sulfurized or chlorinated cutting oil. Do not use this spiral point tap in blind-hole applications, as the chip-forward geometry requires an exit path for chip evacuation.