Heli-coil 3CPA Hand Sti Tap 10-24 Unc H3 Plug Chamfer

Product Description

The HELI-COIL 3CPA is a hand STI tap designed for cutting internal threads to accept Heli-Coil screw thread inserts. Ground to a 10-24 UNC thread form with an H3 thread limit and 3-flute geometry, this tap cuts clean threads in a single pass when used by hand. The plug chamfer style provides 3 to 5 lead threads for easy starting in through-hole applications. Manufactured from high speed steel with a bright finish, it delivers reliable performance across a range of base materials. Thread length is 1 inch and overall length is 2.5 inches. Licensed machinists, maintenance technicians, and HVAC or plumbing pros use STI taps to restore stripped threads in equipment housings and fittings.

This tap is used wherever a 10-24 UNC thread needs to be oversized to accept a wire-type thread insert. Common applications include repairing stripped threads in aluminum compressor housings, cast iron valve bodies, and steel equipment frames. The plug chamfer makes it suitable for through-holes and deep blind holes with adequate clearance. It is intended for hand-tapping operations, not power drive use.

Key Features

• 10-24 UNC thread form for Heli-Coil insert preparation
• H3 thread limit for close-tolerance thread fitting with class 2B fit
• 3-flute design promotes chip clearance during hand tapping
• Plug chamfer provides 3 to 5 lead threads for easy entry in through-holes
• High speed steel construction for durability across common base materials
• Bright finish with no coating for straightforward inspection after use

Compatibility

Designed as an STI (Screw Thread Insert) tap for use with Heli-Coil style wire thread inserts in 10-24 UNC applications. Intended for hand tapping only.

Installation Notes

Installation is performed by hand tool trades including machinists and maintenance technicians. Always secure the workpiece before tapping and use appropriate cutting fluid for the base material. Apply steady, even pressure and back the tap out periodically to clear chips. Do not use this tap in a power driver, as plug chamfer STI taps are rated for hand operation only.