Osg 1400127705 Thread Forming Tap 1/4-20 Unc Plug Cobalt

Product Description

The OSG 1400127705 is a thread forming tap in the HY-PRO NRT series, designed for cold-forming internal threads without cutting. Unlike cutting taps, thread forming taps displace material rather than remove it, producing stronger threads with no chips to clear. This plug-chamfer tap is built from cobalt steel with a TiN coating to handle elevated heat and abrasion. At 2.5 inches overall length with a 0.594-inch thread length and a 0.255-inch shank diameter, it is sized for standard toolholding in CNC machining centers, drill presses, and tapping heads. It covers 1/4-20 UNC right-hand threads at an H10 thread limit. Machinists, tool and die makers, and production shop personnel install it in ferrous and non-ferrous through-hole applications.

This tap is suited for through-hole threading in alloy steel, carbon steel, die steel, hardened steel, stainless steel, and aluminum. The plug chamfer with 4 to 4.5 chamfered threads makes it appropriate for through-hole work where the tap can pass fully through the workpiece. Its cobalt base material and TiN surface coating provide thermal resistance, making it a practical choice for harder alloys and stainless steel that generate significant heat during tapping. Typical applications include production machining, maintenance and repair operations, and fixture and tooling fabrication.

Key Features

• Thread forming design displaces material to produce chip-free, stronger internal threads
• Cobalt steel construction provides heat resistance for harder workpiece materials including stainless and hardened steel
• TiN coating reduces friction and extends tool life in abrasive materials
• Plug chamfer with 4 to 4.5 chamfered threads optimized for through-hole threading operations
• H10 thread limit provides controlled fit tolerance for 1/4-20 UNC threads
• Right-hand thread direction compatible with standard tapping equipment

Compatibility

Designed for through-hole thread forming in alloy steel, aluminum, carbon steel, die steel, hardened steel, and stainless steel workpieces. Material application codes P and N apply per the manufacturer specification. Compatible with standard 0.255-inch shank toolholders and tapping chucks used in CNC machining centers, drill presses, and hand tapping setups.

Installation Notes

Thread forming taps require adequate lubrication or cutting fluid appropriate to the workpiece material to prevent galling, particularly in stainless steel and aluminum. The pilot hole diameter must be sized correctly for thread forming rather than thread cutting, as forming taps require a larger pilot hole than equivalent cutting taps. Ensure the spindle and toolholder are properly aligned before engaging the tap to avoid thread distortion or tap breakage. A qualified machinist or tooling technician should verify feed rate and speed settings before production runs.