3M Scotch-weld 7100039231 Threadlocker Red 50 Ml TL71

Product Description

The 3M SCOTCH-WELD 7100039231 is a high-strength, red liquid threadlocker formulated to permanently secure threaded fasteners against vibration loosening and corrosion. Part of the TL71 series, this anaerobic adhesive cures at room temperature inside metal fastener assemblies and delivers a breakaway torque range of 180 to 410 lb./inch. It is dispensed from a 50 mL bottle, making it well-suited for shop benches and field service kits. Licensed HVAC technicians, plumbers, pipefitters, and mechanical contractors use this product to lock critical fasteners on equipment where inadvertent loosening would create a service or safety hazard.

This threadlocker is designed for fasteners ranging from 1/2 inch to 1 inch in diameter. The high-strength formula is appropriate for applications where disassembly is not routinely expected, such as structural hardware, heavy-duty mechanical assemblies, and equipment subject to sustained vibration or high-cycle loads. With a working time of 20 minutes and a full cure time of 24 hours, the assembly can be handled during initial setup while achieving full mechanical strength overnight. The red color provides a visual indicator that a permanent-grade threadlocker has been applied.

Key Features

• High-strength bond — breakaway torque of 180 to 410 lb./inch on 1/2 inch to 1 inch fasteners
• Wide service temperature range: -65 degrees F minimum to 300 degrees F maximum operating temperature
• 20-minute working time allows positioning adjustments before cure begins
• Full cure achieved in 24 hours at room temperature
• Removal possible with hand tools combined with heat when disassembly is required
• Meets MIL-S-46163A military specification for anaerobic threadlocking compounds
• Liquid form in a 50 mL bottle provides controlled application with minimal waste

Compatibility

Designed for use on metal threaded fasteners in the 1/2 inch to 1 inch diameter range; suitable for typical industrial, mechanical, and trade-service applications where a permanent high-strength threadlocking compound is specified per series TL71 requirements.

Installation Notes

Clean and degrease mating threads thoroughly before applying the threadlocker; oil, grease, or thread sealant residue will inhibit anaerobic cure. Apply a controlled amount to the male thread and assemble immediately within the 20-minute working window. Do not apply heat to accelerate cure on assemblies with nearby elastomers, seals, or sensitive components. When removal is required, apply localized heat and use appropriate hand tools — follow the equipment manufacturer's procedure and applicable codes for fastener torque and service.