Liner lock

A liner lock is a locking mechanism for folding knives where a thin steel spring inside the handle secures the blade in the open position. It is one of the most common lock types found on modern pocket knives.

What is a liner lock

A liner lock uses a bent steel liner inside the handle. When the blade is opened, the liner shifts into the blade’s path and blocks it from closing. To fold the knife, you simply push the liner aside with your finger.

How it works:

• The blade opens to its full position
• The liner springs into place behind the blade tang
• The blade is locked against closing
• Pushing the liner aside releases the lock

Advantages and disadvantages

Liner lock vs frame lock

Both locks work on the same principle but differ in construction:

• Liner lock: A thin steel liner sits inside the handle, which can be made from various materials (G10, plastic, wood)
• Frame lock: Part of the metal handle itself acts as the lock, resulting in a sturdier construction overall

A liner lock is lighter and more affordable, while a frame lock offers greater strength and durability.

Use and maintenance

The liner lock is well suited for EDC knives and everyday tasks. It is not designed for prying or extreme loads. To keep it working properly:

• Clean the mechanism regularly to remove dirt and debris
• Check liner engagement (at least 50% contact area)
• Lubricate the pivot and liner with silicone oil
• Avoid lateral stress on the blade

Related terms: frame lock, folding knife, EDC, axis lock, back lock