Cleveland
Cleveland C55120 Straight Flute Hand Tap 5/16"-18 Plug
Creates 5/16"-18 UNC threads in through-holes using high-speed steel with TiN coating
- TypeTaps
- Creates precise UNC threads with 5/16"-18 straight-flute tap
- Plug chamfer starts threads easily in through-holes
- High-speed steel with TiN coating resists wear
- 13 in thread length cuts full-depth threads
- 72 in overall length fits standard tap handles
Cleveland C55120 Straight Flute Hand Tap
The Cleveland C55120 is a straight flute hand tap designed for creating internal UNC threads in a variety of materials. It features a 5/16"-18 thread size with a plug chamfer for general-purpose threading tasks. Constructed from High Speed Steel with a TiN coating, it offers enhanced wear resistance and longer tool life. The right-hand cutting direction suits standard threading applications.
Suited for maintenance.
This tap suits mechanics and machinists cutting new threads or chasing damaged ones in steel, cast iron and non-ferrous metals. The H3 thread limit provides a Class 2B fit for standard fastener compatibility. Buyers needing bottoming taps for blind holes or spiral-point taps for high-volume through-hole work should look at different tap styles. It is not intended for automated machine tapping without proper holders.
Capacity and headroom for 5/16"-18 UNC threads
The tap comfortably handles through holes and blind holes with adequate clearance beyond the 1.13 inch thread length. Its 2.72 inch overall length provides reach for deeper workpieces. The 75 percent thread drill size F prepares the correct hole for engagement. Headroom runs out when hole depth exceeds the thread length or when material hardness demands specialised carbide or cobalt tooling.
Highlights
- Creates precise UNC threads with 5/16"-18 straight-flute tap
- Plug chamfer starts threads easily in through-holes
- High-speed steel with TiN coating resists wear
- 13 in thread length cuts full-depth threads
- 72 in overall length fits standard tap handles
Specifications
| Brand | CLEVELAND |
|---|---|
| Type | Taps |
Questions about this item
What size tap wrench or handle is required to turn the 5/16"-18 Cleveland C55120 tap?
The tap has a standard square shank for a 5/16" tap; use a tap wrench sized for that shank, typically a #5 or adjustable wrench covering the 5/16" range.
Can I use this plug tap after a taper tap to finish threads in a through-hole in steel?
Yes, the plug chamfer with 3–5 threads is designed to follow a taper tap and cut full threads to the bottom of a through-hole in steel.
How do I verify the finished 5/16"-18 UNC threads meet the 2B class of fit?
Check the threads with a 5/16"-18 UNC 2B go/no-go thread gauge; the go gauge should pass fully and the no-go gauge should not enter more than three turns.
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