Heli-coil 4687-10 Hand Sti Tap M10 X 1.5 Metric Coarse

Product Description

The HELI-COIL 4687-10 is a hand STI (Screw Thread Insert) tap designed to cut the oversized internal threads required for installing HELI-COIL wire thread inserts. Ground to an M10 x 1.5 Metric Coarse thread form with a D3 thread limit, this tap features 4 flutes and a plug chamfer for starting ease in through-holes and blind holes with adequate clearance. The body is machined from high-speed steel with a bright uncoated finish, providing solid wear resistance across a range of common materials. Overall length is 3.375 inches with a thread length of 1.657 inches.

This tap is intended for use by machinists, maintenance technicians, and trade professionals performing thread repair or insert installation in aluminum, magnesium, mild steel, and stainless steel workpieces. It is a standard hand-tap application - turned with a tap wrench rather than a machine spindle - and is sized specifically for the HELI-COIL insert installation process rather than standard thread cutting. Typical applications include field repair of stripped threads in engine components, equipment housings, and structural fastener locations.

Key Features

• M10 x 1.5 Metric Coarse thread form ground to D3 thread limit for accurate insert-tap fit
• Plug chamfer (3-5 threads) allows starting in through-holes and most blind-hole applications
• 4-flute geometry provides balanced cutting action and chip clearance
• High-speed steel construction handles aluminum, magnesium, mild steel, and stainless steel
• Bright uncoated finish - no coating buildup concerns in close-tolerance STI thread forms
• Compact OAL of 3.375 inches suits confined repair environments

Compatibility

Designed for use in the HELI-COIL STI thread insert installation process for M10 x 1.5 Metric Coarse insert sizes. Compatible with aluminum, magnesium, mild steel, and stainless steel base materials as stated by the manufacturer.

Installation Notes

This tap is intended for hand use with a standard tap wrench - do not chuck it in a power driver or CNC spindle. Secure the workpiece before tapping, apply appropriate cutting fluid for the base material, and back the tap off periodically to break and clear chips. Follow the HELI-COIL installation sequence: drill to the correct insert drill size, tap with this STI tap, then install the insert with the proper installation tool.