Osg 1400107905 Thread Forming Tap 5-40 Unc Cobalt Tin

Product Description

The OSG 1400107905 is a thread forming tap in the HY-PRO NRT series, designed for cold-forming internal threads without cutting. It produces 5-40 UNC right-hand threads in blind holes using a modified bottoming chamfer with 2 to 2.5 chamfered threads. The tap is manufactured from cobalt steel and carries a titanium nitride (TiN) coating to extend tool life and reduce friction in demanding materials. Overall length is 1.938 inches, with a shank diameter of 0.141 inches and a tapping depth of 0.626 inches. Thread limit is H5 with a Class 2B fit. This is a single-pass cold-forming tool installed by machinists and toolroom technicians in production and maintenance environments.

This tap is suited for blind hole threading operations in a range of ferrous and non-ferrous materials including alloy steel, carbon steel, die steel, hardened steel, stainless steel, and aluminum. The modified bottoming chamfer allows threading close to the bottom of a blind hole, making it effective in tight-depth applications common in precision machining, fixture fabrication, and component repair work. The HY-PRO NRT series is built for use without coolant-through capability, relying on the TiN coating and cobalt substrate to manage heat in dry or flood-coolant setups.

Key Features

• Modified bottoming chamfer with 2 to 2.5 chamfered threads for threading near blind hole bottoms
• Cobalt steel construction provides heat resistance in tough alloys and hardened steels
• TiN coating reduces friction and extends tool life across material applications
• Thread forming (chipless) design eliminates chip evacuation concerns in blind holes
• H5 thread limit with Class 2B fit for consistent thread quality
• Right-hand thread direction, 40 threads per inch, 5-40 UNC standard

Compatibility

Designed for blind hole thread forming in alloy steel, aluminum, carbon steel, die steel, hardened steel, and stainless steel workpieces requiring 5-40 UNC internal threads at a Class 2B fit. Material application codes P and N apply.

Installation Notes

Thread forming taps require a precisely sized forming hole — consult a forming tap drill chart for the correct pilot hole diameter for 5-40 UNC before use. Secure the workpiece and use a calibrated tap wrench or CNC tapping head set to appropriate feed rates to avoid tap breakage. Apply tapping fluid or cutting oil appropriate to the workpiece material even in non-coolant-through setups to reduce galling. Inspect the tap for wear or chipping before each use, as cobalt tools can fracture without visible pre-failure in hardened materials.