Loctite Threadlocker 271 high-strength red 50 ml — metal fasteners up to 1", UV-tracer

Loctite 271 is a red, high-strength, low-viscosity threadlocker formulated to permanently lock and seal metal fasteners up to 1" diameter while resisting light oil contamination.

Loctite 271 (50 ml) is a methacrylate-based threadlocking adhesive designed for demanding industrial and maintenance applications. Its low viscosity lets it penetrate threads easily; once cured it forms a durable bond that prevents loosening from vibration and secures assemblies of steel, brass, stainless steel and other metals. This formula gives a balance of strong retention with practical work times for assembly and repair.

How quickly does this threadlocker set on different metals?

Cure (fixture) times depend on substrate: brass and steel cure faster than stainless steel. These fixture times are measured on steel, brass and stainless steel under typical conditions; full cure strength develops over time and with reduced clearances between mating parts.

• Steel fixture time: about 10 minutes
• Brass fixture time: about 5 minutes
• Stainless steel fixture time: about 15 minutes
• Full cure increases with close-fitting threads and room temperature

What kinds of fasteners and environments is this product suitable for?

LOCTITE 271 is optimized for metal fasteners and works well on bolts, studs and machine screws up to roughly 1 inch in diameter. It tolerates slight contamination from industrial oils, making it useful in pre-serviced or mildly oily assemblies. Avoid heavily contaminated or greased parts for best results.

• Intended for metal-to-metal threaded joints
• Effective on fasteners up to ~1" diameter
• Resistant to slight industrial oil contamination
• Not recommended for heavily soiled or greasy threads

How strong is the bond and how will I know it’s cured?

The cured adhesive delivers high retention and measurable breakaway torque on common metric fasteners. It also contains a fluorescent tracer that lights up under UV, which helps confirm coverage and location during inspections.

• Breakaway torque example: M10 bolts ~26 Nm
• High-strength final bond suitable for fixed assemblies
• Fluoresces under UV for quick inspection of application
• Strength builds over time to full cure

How do I apply Loctite 271 safely and effectively?

Application is straightforward: dispense from the 50 ml bottle onto clean threads, assemble parts, and allow the product to set. For best performance, remove heavy oils, paints or dirt before applying and follow industrial safety guidance for ventilation and skin contact.

• Apply a few drops to the male threads and assemble parts
• Wipe away excess; allow fixture time before handling
• Use on parts with reasonable fit for faster cure
• Manufactured in the United States; follow safety data sheet instructions

Who this is for: Loctite 271 50 ml is aimed at technicians, maintenance professionals, machinists and serious DIYers who need a dependable, high-strength threadlocker for metal fasteners. It’s well suited to factory assemblies, repair shops and applications where vibration resistance and permanent locking are required, while still allowing inspection via UV when needed.