Heli-coil 02CSB Spiral Point Sti Tap 2-56 Unc Plug Hss

Product Description

The HELI-COIL 02CSB is a spiral point STI tap designed to cut threads in pre-drilled holes for Heli-Coil thread insert installation. It features a 2-56 UNC thread size, a plug chamfer for through-hole threading, and a 2-flute spiral point geometry that pushes chips ahead of the cut. The tap is manufactured from high-speed steel (HSS) with a bright, uncoated finish and carries an H1 thread limit and a 3B class of fit. Machinists, maintenance technicians, and shop professionals use this tap when restoring or creating threaded holes intended to receive wire thread inserts.

This tap is used in applications where Heli-Coil STI (Screw Thread Insert) inserts are being installed into 2-56 UNC threaded holes. It is suited for light assembly work, precision machining, and thread repair operations in metalworking and maintenance environments. The 2-flute spiral point design makes it effective in through-hole applications where chip evacuation is a priority. The compact overall length of 1.875 inches makes it manageable in tight working areas.

Key Features

• Spiral point geometry pushes chips forward, keeping the cutting zone clear in through-hole applications
• 2-56 UNC thread size with H1 thread limit for accurate STI insert fitment
• Plug chamfer provides a standard starting lead for general-purpose through-hole tapping
• High-speed steel construction offers durability across steel, aluminum, and similar workpiece materials
• 3B class of fit ensures proper tolerance for threaded insert installations
• Bright, uncoated finish allows for easy visual inspection of the cutting edges

Compatibility

Designed for use with Heli-Coil STI UNC thread insert systems requiring a 2-56 thread size tap. This tap prepares the hole to the correct oversized diameter and thread form needed for Heli-Coil wire thread insert installation.

Installation Notes

This tap should be installed and operated by a qualified machinist or maintenance technician familiar with tapping procedures and thread insert systems. Always ensure the workpiece is securely fixtured and the tap is properly aligned before beginning the cut. Use an appropriate cutting fluid for the workpiece material to extend tap life and improve thread quality. Do not reverse the tap under power, as this can damage cutting edges or break the tap in the hole.