Osg 1400143701 Thread Forming Tap 1/2-13 Unc Plug Cobalt

Product Description

The OSG 1400143701 is a thread forming tap in the HY-PRO NRT series, designed for cold-forming internal threads without chip generation. Built from cobalt high-speed steel with a steam oxide coating, this plug-style tap produces 1/2-13 UNC right-hand threads to a Class 3B fit at thread limit H5. The plug chamfer spans 4 to 4.5 threads, making it suited for through-hole threading applications where a gradual lead-in is needed. At 3.375 inches overall length with a 0.367-inch shank diameter, the tap fits standard tap holders used in CNC machining centers, drill presses, and manual tapping setups. Machinists and tool-room technicians are the primary users of this tool.

This tap is rated for through-hole threading operations across a broad range of metallic workpiece materials including alloy steel, carbon steel, die steel, hardened steel, stainless steel, and aluminum. The thread forming method displaces material rather than cutting it, producing stronger threads with a better surface finish than cut-tap alternatives. It is a fit choice for production environments where tool life and thread quality consistency are priorities. No coolant-through capability is present, so flood or external coolant delivery applies.

Key Features

• Cobalt HSS construction provides heat and wear resistance in tough alloy and stainless steel applications
• Steam oxide coating reduces friction and improves lubricity during forming operations
• Plug chamfer (4 to 4.5 threads) delivers controlled lead-in for through-hole work
• Thread forming design eliminates chips, reducing tap breakage risk in blind and through-hole setups
• Class 3B fit with H5 thread limit ensures tight-tolerance thread geometry
• Right-hand thread direction, compatible with standard tapping attachments and CNC rigid-tap cycles

Compatibility

Designed for through-hole threading of 1/2-13 UNC right-hand threads in alloy steel, aluminum, carbon steel, die steel, hardened steel, and stainless steel workpieces. Material application codes P and N apply per the manufacturer classification.

Installation Notes

Thread forming taps require adequate lubrication at the point of contact — use a cutting or tapping fluid appropriate for the workpiece material. Secure the tap in a properly sized tap holder or rigid-tap chuck to prevent run-out and maintain thread accuracy. Ensure the spindle speed and feed rate are set to the tap manufacturer recommendations for the workpiece material before starting the cycle. Do not reverse-cycle without confirming the holder supports reverse-direction torque to avoid tap damage.