How to safely open & close a folding knife

Folding pocket knife on a log
Charlie Cooper / Updated: Mar 29th 2020 / Knives

You can find different types of opening and closing mechanisms in folding knives. A locking mechanism indicates a safety system designed to prevent the blade from accidentally and dangerously closing once opened while cutting or stabbing.

Let’s start by identifying the three most common mechanisms:


In the liner-lock, the load-bearing structure consists of two pieces of metal that fit together as one solid piece. The edge is the front part, and it uses the pivot to fully extend. Behind the heel of the blade, another piece of metal fits in when you reach maximum extension of the blade preventing it from closing.

The spring of the lock release disengages this system, allowing the inner piece that fits behind the blade to get back in the original position on the side. This way, you use the spring to align or misalign two pieces of metal that rest next to each other when you fold the knife.


Similar to the Liner-lock, in the frame-lock architecture, the piece that holds the blade is the frame itself. The spring keeps a part of the frame from directly sinking into the inner part of the handle. In large knives, manufacturers use titanium to ensure the frame can hold the pressure. To fold it, you push the lock release to make the spring return to the rest position and releasing the cutting edge.


This locking system uses a lever, with a locking bar that engages the tang and the upper part of the heel of the blade when you extend the blade. Traditionally set on the rear of the handle, the spring of the lock release pushes this lever down to disengage the lock.

Some brands modify slightly this mechanism, but the goal is to create a more symmetrical mechanism. The Liner-lock design presents a shape that right-handed can enjoy better than left-handed. If you are left-handed, you will probably enjoy the Back-Lock more.

To fold the knife, push the rear lock release with the thumb. Sometimes you can find the lock release at the very end of the handle, other times in the middle.

How to safely open and close a folding knife: step by step

To safely open a folding knife:

Use your predominant hand to hold the knife so that the back of the edge can move up following an archold the handle by placing the thumb on the flipper and the rest of the fingers on the other side of the handle, keeping contact with the tang and the handle only (your fingers must never touch the side where the edge gets out)use the flipper near the pivot at the same time with your thumb or use the index and thumb of your free hand to extend the blade. Extend the blade fully until you hear the sound of the locking system.

To safely close a folding knife, you start with the same safe placement of the fingers:

slowly press the lock release with one hand while you hold the blade and gently tilt it toward the handle remove your fingers from the lock release as soon as the blade moves put your free hand back to the handle in the starting position with your fingers safely on the side of the handle push the blade inside the handle.