Osg 1400138200 Thread Forming Tap 3/8-24 Unf Plug Cobalt

Product Description

The OSG 1400138200 is a thread forming tap in the HY-PRO NRT series, designed for cold-forming internal threads without cutting. It produces a 3/8-24 UNF right-hand thread using a plug chamfer with 4 to 4.5 chamfered threads for controlled entry. The tap is manufactured from cobalt high-speed steel with a bright finish and carries a H4 thread limit. Overall length is 2.9380 inches with a tapping depth of 0.7520 inches of usable thread length and a maximum tapping depth of 1.2520 inches. Installation requires a tapping driver or CNC rigid tap cycle. This tap is used by machinists and toolroom professionals in production and maintenance environments.

This tap is suited for through-hole threading applications across a range of ferrous and non-ferrous workpiece materials. It is appropriate for use in alloy steel, aluminum, carbon steel, die steel, hardened steel, and stainless steel. The cobalt construction supports elevated heat resistance in harder materials. The plug chamfer makes it suitable for through-holes where the tap can pass completely through the workpiece. It fits standard tap holders and collet-style tapping chucks sized for a 0.3810-inch shank diameter.

Key Features

• Cold-forms 3/8-24 UNF right-hand threads without producing chips, reducing clogging in blind or through applications
• Cobalt construction provides improved heat and wear resistance compared to standard M2 HSS
• Plug chamfer with 4 to 4.5 chamfered threads for progressive entry and reduced axial force on startup
• H4 thread limit supports consistent fit class across production runs
• Bright finish - no coating interference with base material properties
• Compatible with through-hole threading in alloy steel, aluminum, carbon steel, die steel, hardened steel, and stainless steel

Compatibility

Designed for through-hole threading applications in alloy steel, aluminum, carbon steel, die steel, hardened steel, and stainless steel workpieces. Material application codes P and N are assigned to this tap per OSG classification. Fits standard tap holders accepting a 0.3810-inch shank diameter.

Installation Notes

Thread forming taps require proper lubrication matched to the workpiece material - cutting oil for ferrous metals and appropriate lubricant for aluminum. Use a rigid tapping cycle or floating tap holder to control axial feed. Ensure the tap is aligned perpendicular to the workpiece surface before starting. Always secure the workpiece and confirm spindle speed and feed rate are set per the tap manufacturer recommendations for the specific material being tapped.