Cleveland
Cleveland C55389 Spiral Point Tap 5/16-24 UNF H4 3 Flute
A spiral-point tap cuts 5/16-24 UNF threads in through-holes, using three flutes and a TiCN-coated high-speed steel body for longer wear life
- Cuts 5/16-24 UNF threads cleanly with spiral-point chip ejection
- Three-flute H4 high-speed steel tap delivers 2B class fit
- TiCN coating extends tool life in steel and stainless
- 75 percent thread drill size I ensures accurate hole preparation
- Right-hand plug design starts easily in through or blind holes
Cleveland C55389 Spiral Point Tap
The Cleveland C55389 is a spiral point tap designed for creating UNF threads in through-hole applications. It features a 5/16 inch -24 thread size with an H4 thread limit for a 2B class of fit. The tool is manufactured from High Speed Steel with a TiCN coating for extended wear resistance. Right-hand cutting direction and three flutes support efficient chip evacuation forward through the hole.
Suited for through-hole threading
This tap suits machinists and maintenance technicians cutting 5/16-24 UNF threads in steel, stainless steel or similar ferrous materials where forward chip ejection is preferred. The 75 percent thread drill size I requirement must be observed for correct thread engagement. It is not for blind holes where chips cannot escape forward, nor for left-hand thread requirements, and the fixed H4 limit will not suit applications demanding a different class of fit or thread tolerance.
Standard tap installation
Install by securing the tap in a suitable holder aligned with a pre-drilled hole matching the 75 percent thread drill size I. Apply appropriate cutting fluid and advance with steady pressure; the spiral point design pushes chips ahead of the cut. Common issues include tap breakage from misalignment or insufficient lubrication, and oversize threads if the drill size is incorrect or the workpiece material differs significantly from the intended ferrous range.
Highlights
- Cuts 5/16-24 UNF threads cleanly with spiral-point chip ejection
- Three-flute H4 high-speed steel tap delivers 2B class fit
- TiCN coating extends tool life in steel and stainless
- 75 percent thread drill size I ensures accurate hole preparation
- Right-hand plug design starts easily in through or blind holes
Specifications
| Brand | CLEVELAND |
|---|
Questions about this item
What size drill bit do I need before using this 5/16-24 UNF tap?
Use a number I drill bit to create the 75 percent thread hole before tapping.
Will this H4 limit tap fit my existing 2B class UNF gauges?
Yes, the H4 thread limit is manufactured for a 2B class of fit on 5/16-24 UNF threads.
How can I confirm the tap is cutting correctly after setup?
Check that chips are pushed forward ahead of the tap and the threads measure to 2B specifications.
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