Osg 1400115201 Thread Forming Tap 8-32 Unc Plug Cobalt

Product Description

The OSG 1400115201 is a plug-chamfer thread forming tap designed for 8-32 UNC right-hand threading in through-hole applications. Built from cobalt high-speed steel and finished with a steam oxide coating, this tap forms threads by displacing material rather than cutting it, resulting in stronger thread walls and no chips to clear. It measures 2.125 inches in overall length with a thread length of 0.374 inches and a shank diameter of 0.168 inches. The H3 thread limit and 3B class of fit make it well-suited for production environments where consistent thread quality is required. Installed by machinists and maintenance technicians in metalworking shops and industrial facilities.

This tap is suited for through-hole threading in a wide range of ferrous and non-ferrous metals including alloy steel, carbon steel, die steel, hardened steel, stainless steel, and aluminum. The plug chamfer with 4 to 4.5 chamfered threads allows the tap to start easily in pre-drilled through holes. It is part of the OSG HY-PRO NRT series, which is engineered for forming threads in materials that benefit from cold-working rather than chip-producing cutting taps. Typical applications include fastener hole preparation in structural components, tooling fixtures, and machine assemblies.

Key Features

• Cobalt construction provides heat and wear resistance in demanding alloy and stainless steel applications
• Steam oxide coating reduces friction and aids lubrication retention during tapping
• Thread forming design eliminates chips, reducing tap breakage risk in blind and through holes
• H3 thread limit with 3B class of fit ensures consistent, gaugeable thread quality
• Plug chamfer (4 to 4.5 threads) for reliable starting in through-hole setups
• Right-hand thread direction, 32 threads per inch, 8-32 UNC standard

Compatibility

Designed for through-hole thread forming in alloy steel, carbon steel, die steel, hardened steel, stainless steel, and aluminum per OSG material application codes P and N. Part of the OSG HY-PRO NRT series 14001.

Installation Notes

Thread forming taps require a properly sized forming tap drill hole, which is larger than a standard cut tap drill — consult OSG or standard tap drill charts for the correct forming tap drill diameter for 8-32 UNC. Use a recommended tapping fluid or cutting oil appropriate for the workpiece material, particularly when working with stainless or alloy steels. Secure the workpiece and use a calibrated tapping machine or tapping attachment to maintain axial alignment and avoid tap breakage. Inspect the tap for wear or chipping regularly, as cobalt taps in hardened materials are subject to fatigue under repeated use.