Loctite® 243 Threadlocker 10 ml

Loctite® 243 is a medium-strength threadlocker designed for metal screw joints. It helps prevent screws from vibrating loose or backing out due to movement or impacts. It suits belt screws (Chicago screws), metal hardware, and other small threaded joints. Once cured, you can still take the joint apart using standard hand tools.

How it works

• It cures when confined in the absence of air between close-fitting metal surfaces inside the thread. It won't glue your screw to the webbing, leather, or any other material it passes through.
• It only locks the metal thread—the exact spot where the screw thread meets the internal thread of its counterpart.
• Any excess pushed outside the joint stays liquid, so just wipe it off after tightening.

How to apply

Give the bottle a good shake before use. Adapt your application to the screw's diameter, thread length, and pitch. For tiny, fine threads (like M3), apply a small drop inside the internal thread or spread a thin layer directly onto the screw threads.

• A massive drop right at the tip might just get squeezed out when tightening and miss the active threads entirely. On the flip side, too little might not cover enough surface.
• If the liquid is too thick and sits on the edge of the hole, gently coax it inside with a toothpick.
• You don't need to flood the hole—just make sure you coat the thread surfaces that will actually engage when tightened.

Curing speed

How fast it sets depends on the type of metal and room temperature. It cures much faster on brass, bronze, and copper. For stainless steel, aluminium, titanium, or plated parts, it takes a bit more patience. Also, expect a slower cure at cooler temperatures (15–18 °C) compared to a warm room.

Important: Don't test the joint the second you assemble it. Give it plenty of time to fully cure before putting it under stress, especially if you're working with stainless steel or surface-treated screws.