Osg 1626001708 Thread Forming Sti Tap 10-32 Unf H3

Product Description

The OSG 1626001708 is a thread forming STI tap designed for cutting 10-32 UNF internal threads in a wide range of metals. Unlike cutting taps, thread forming taps displace material rather than remove it, producing stronger threads with no chips to clear. This tap is built from high-speed steel, carries an H3 thread limit for close-tolerance work, and features a semi-bottoming chamfer for threading holes that stop short of full through-thread depth. The V finish on the flute surfaces reduces friction during forming. It is used primarily by machinists, toolroom technicians, and maintenance professionals working on precision fastener applications.

This tap is suited for production and repair tapping operations in job shops, manufacturing facilities, and maintenance environments. The 10-32 UNF thread size is common in instrument panels, electronics enclosures, and precision mechanical assemblies. The H3 thread limit and Class 3B fit designation make it appropriate where tight thread tolerances are required. Its semi-bottoming chamfer allows threading close to the bottom of blind holes without requiring a bottoming tap as a finishing step in most applications.

Key Features

• Thread forming design displaces material to produce chip-free, stronger threads
• High-speed steel construction provides durability across a broad range of workpiece materials
• H3 thread limit and Class 3B fit for close-tolerance 10-32 UNF threads
• Semi-bottoming chamfer allows threading near the bottom of blind holes
• V finish reduces friction and aids lubricant retention during forming
• Compatible with carbon steel, alloy steel, stainless steel, aluminum, nickel, titanium alloy, and hardened steel workpieces

Compatibility

Rated for use in carbon steel, alloy steel, stainless steel, aluminum, nickel, hardened steel, and titanium alloy workpieces. Produces 10-32 UNF threads conforming to Class 3B fit specifications.

Installation Notes

Thread forming taps require a specific tap drill size larger than standard cutting tap drill sizes — consult a thread forming drill chart for the correct pilot hole diameter before starting. Apply appropriate tapping fluid for the workpiece material; thread forming generates more torque than cutting taps, so proper lubrication is critical. Secure the workpiece firmly and use a tap handle or tapping attachment that allows controlled, consistent torque. Never force the tap if resistance increases sharply, as thread forming taps are susceptible to breakage if the pilot hole is undersized or the tap is misaligned.