Heli-coil 05CPB Hand Sti Tap 5-40 Unc H1 Plug Chamfer

Product Description

The HELI-COIL 05CPB is a hand STI tap designed for cutting internal threads in pre-drilled holes to accept Screw Thread Inserts. Built from high-speed steel with a bright, uncoated finish, this tap cuts 5-40 UNC threads to an H1 thread limit. The plug chamfer allows starting in through-holes or blind holes where some lead-in length is acceptable. It features 3 flutes for chip clearance and smooth thread formation. Overall length is 2.125 inches, with a thread length of 0.75 inches. The shank diameter measures 0.168 inches, and the square size is 0.131 inches. This tap is used by machinists, maintenance technicians, and trade professionals performing thread repair or insert installation work.

The 05CPB is sized for 5-40 UNC thread repair applications where a Heli-Coil or compatible STI insert will be installed. It is suited for use in ferrous and non-ferrous base materials where the parent thread has been damaged or where insert-thread reinforcement is required. The plug chamfer style makes it appropriate for through-holes and sufficiently deep blind holes. It is commonly used in aerospace, HVAC equipment, pump housings, motor frames, and general industrial maintenance settings where small fastener threads need to be restored or reinforced.

Key Features

• 5-40 UNC thread form with H1 thread limit for close-tolerance STI thread cutting
• Plug chamfer style for versatile use in through-holes and deep blind holes
• 3-flute design promotes chip evacuation and smooth thread formation
• High-speed steel construction for durability across ferrous and non-ferrous materials
• Bright, uncoated finish - no coating buildup to affect thread tolerance
• Class of fit 3B for precise, tight-tolerance thread engagement

Compatibility

Designed for use with Heli-Coil and compatible STI thread insert systems in 5-40 UNC applications. Intended for hand tapping operations requiring an H1 thread limit and 3B class of fit.

Installation Notes

This tap is intended for hand operation using a tap wrench - do not use in a power driver without appropriate torque control. Ensure the base material hole is drilled to the correct STI tap drill size before threading. Apply cutting fluid appropriate to the base material to extend tool life and improve thread quality. Follow all applicable safety practices when working with sharp cutting tools, and inspect the tap for wear or chipping before each use.