Osg 1400139200 Thread Forming Tap 7/16-14 Unc Cobalt

Product Description

The OSG 1400139200 is a thread forming tap in the HY-PRO NRT series, designed for cold-form tapping of internal threads without cutting or producing chips. Built from cobalt high-speed steel with a bright finish, this tap handles 7/16-14 UNC threads in blind hole applications. It features a modified bottoming chamfer with 2 to 2.5 chamfered threads, allowing thread forming to begin close to the bottom of a blind bore. The H5 thread limit provides the tolerance control required for consistent thread fit. Overall length is 3.156 inches with a tapping depth of 1.713 inches. Machinists and toolroom professionals use this tap in CNC and manual tapping operations where chip-free threading is required.

This tap is suited for blind hole threading 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 makes it practical for applications where thread engagement must start near the bottom of a shallow blind hole. Right-hand thread direction is standard. No coolant-through feature is present, so flood or brush-applied cutting fluid is used at the spindle during operation.

Key Features

• Thread forming design eliminates chips, reducing hole cleanup and breakage risk in blind bores
• Cobalt construction provides heat and wear resistance in harder workpiece materials
• Modified bottoming chamfer with 2 to 2.5 chamfered threads for near-bottom thread forming
• H5 thread limit for consistent tolerance control on 7/16-14 UNC threads
• Right-hand thread direction, compatible with standard tapping heads and CNC rigid tapping
• Bright finish with no coating, suitable for use with standard tapping lubricants

Compatibility

Designed for blind hole threading in alloy steel, aluminum, carbon steel, die steel, hardened steel, and stainless steel workpieces. Material application codes P and N indicate suitability for steel and non-ferrous material groups per standard tooling classification.

Installation Notes

Thread forming taps require a specific tap drill size larger than that used for cut taps — consult the appropriate forming tap drill chart for 7/16-14 UNC before drilling. Secure the workpiece and ensure the tap is properly aligned to the hole axis before engagement to avoid tap breakage. Use a suitable tapping compound or cutting oil; do not run dry. This tap is intended for installation by qualified machinists familiar with tapping speeds, feed rates, and blind hole depth management.