Loctite Threadlocker 50ml (Type 271) — Red High-Strength Threadlocker for Metal Fasteners, UV-Fluorescent, Vibration-Resistant

Loctite Threadlocker 50ml (type 271) is a red, high-strength, low-viscosity methacrylate adhesive designed to lock and seal metal threaded fasteners securely.

This 50ml bottle of Loctite 271 delivers a dependable, permanent threadlocking solution for bolts and screws up to 1 inch (25 mm) diameter. Engineered for tough industrial conditions, it bonds metal parts and resists moderate oil contamination while curing to a strong, vibration-resistant joint. The formula fluoresces under UV light for easier inspection and traceability in maintenance routines.

How quickly does this threadlocker set and hold parts together?

The product reaches initial fixture within minutes on typical metals, providing a fast work pace while still allowing proper positioning. Full strength develops after cure, giving a durable, vibration-resistant bond.

• Steel fixture time: approximately 10 minutes
• Brass fixture time: approximately 5 minutes
• Stainless steel fixture time: approximately 15 minutes
• Final cure depends on materials, gap size and temperature

Which fasteners and materials is this threadlocker suitable for?

Loctite 271 is formulated for metal fasteners and performs well across a broad range of ferrous and non-ferrous alloys. It is intended for permanent locking of bolts and screws where high strength and resistance to loosening are required.

• Suitable for all metal fasteners up to 1 in (25 mm) diameter
• Designed to permanently seal threaded connections
• Works on steel, stainless steel, brass and many other metals
• Not recommended for use on plastics without compatibility testing

How does it cope with contamination like oils or greases?

The adhesive tolerates slight industrial oil contamination, making it practical for maintenance and assembly environments where perfect cleanliness is not always achievable. For best, most consistent results, clean heavily contaminated surfaces before application.

• Will tolerate light oil residues without immediate failure
• Heavily soiled threads should be degreased for optimal cure and strength
• Improves long-term reliability compared with unsealed threaded joints
• UV fluorescence helps verify application even on oily surfaces

What kind of performance can I expect from this formula?

This high-strength threadlocker produces robust breakaway torque and resists vibration and shock. It is a permanent solution where disassembly is not intended; controlled removal typically requires heat or heavy mechanical force.

• Breakaway torque example: about 26 Nm on an M10 bolt
• High-strength bond resists loosening from vibration
• Fluoresces under UV for quick inspection of treated fasteners
• Low viscosity for easy application into threads and crevices

Who is this for: Loctite Threadlocker 50ml (271) is aimed at industrial technicians, maintenance crews, fabricators and skilled DIYers who need a permanent, high-strength lock for metal fasteners. Choose this product when you require a reliable thread seal that tolerates light contamination, cures quickly on common metals and can be inspected under UV light. If you need a removable or low-strength option for frequent disassembly, consider a different Loctite grade that matches that requirement.