Heli-coil 5406-12 Thread Repair Kit M12x1.5 18 Inserts

Product Description

The HELI-COIL 5406-12 is a threaded insert thread repair kit designed to restore damaged or stripped M12x1.5 metric fine threads to full load-bearing strength. The kit includes everything needed for a complete repair: a drill bit, tap, installation tool, tang removal tool, and 18 wire thread inserts. The inserts measure 18mm in length, providing solid thread engagement in ferrous and non-ferrous base materials. This kit is installed by machinists, maintenance technicians, and mechanical trades professionals working on engines, equipment housings, and structural assemblies where thread integrity is critical.

This kit is suited for metric fine thread repair applications in residential, commercial, and industrial maintenance settings. Common use cases include restoring cylinder head bolt threads, transmission case threads, and precision equipment housings where the M12x1.5 thread form is specified. The kit provides six inserts per size length across three length variations for a total of 18 inserts, allowing multiple repairs per kit. The metric fine thread standard ensures dimensional accuracy for close-tolerance fastener applications.

Key Features

• Complete kit includes drill bit, tap (part number 4976-12), installation tool (part number 4973-12), and tang removal tool sized 25/64
• M12x1.5 metric fine thread size for close-tolerance fastener applications
• 18mm insert length provides deep thread engagement in the repaired bore
• 18 wire thread inserts included, with 6 inserts per size length
• Insert package part number R3745-12 for reorder of inserts only
• Thread standard: Metric Fine - maintains original fastener specification after repair

Compatibility

Designed for repair of M12x1.5 metric fine threaded holes in metal base materials including steel, aluminum, cast iron, and other machinable alloys where stripped or damaged internal threads require restoration to original specification.

Installation Notes

Installation is performed by a qualified machinist or mechanical technician. Always de-energize, depressurize, or safely isolate the equipment before beginning thread repair work. Use the included drill and tap in sequence before driving the insert with the provided installation tool, then break off the tang using the included tang removal tool. Follow the drill depth and tap depth guidance appropriate to the base material to avoid breakthrough or misalignment.