Pocket Knife Lock Types
Think of the lock on your pocket knife like the one on your front door. You want a dependable lock that will keep the danger at bay, yet also be easy to open and close. A knife lock should ensure great lockup and provide maximum confidence in the blade staying right where you want it. The lock is likely the most integral part of a knife design because nothing will ruin your day faster than a sharp blade closing on those freshly manicured digits you just had done at the spa. Ain't nobody want stitches, amigos.
Michael Walker perfected the idea of a liner of the knife that is tensioned inward. This tension on the lock keeps the blade closed with a detent ball and secures it open on the lock face. To close, push the lock outward, allowing the blade to fold. Fun fact (heard through the grapevine, likely true): Michael Walker never defended his patent on the liner lock, so it entered the public domain, and he never received royalties for its use. It's an interesting twist on the most prolific modern locking mechanism.
The Integral Lock or “frame lock” is a Chris Reeve invention that works like a liner lock, but is cut from the frame of the handle. This creates an integrated lock and handle in a single piece. Frame locks are made from Titanium or stainless steel. When made well, frame locks are extremely strong and dependable. If you're new to the knife game, you may find that frame locks are hard to open (guilty as charged over here!). You likely have your finger on the frame lock, thus pushing the detent ball into the blade. Move your index finger to the pocket clip, and it will likely open like a dream.
Also called a “plunge lock,” the button lock is common on automatic knives. A cutout in the blade tang engages with a spring-loaded button to hold the knife open. To release, push the button down and swing the blade closed. It is also commonly used on manual action flipper knives, and Brian Tighe seems to have a penchant for that particular configuration.
A simple design with a tensioned backspring that presses against the blade to keep it closed. To open, a nail nick is used to overcome the spring tension. The backspring sits against the backstop to hold the blade open as a “non-locking folder.” Tension keeps the blade open, but care is needed to avoid putting pressure in the wrong direction and closing the blade unexpectedly. Traditional knives like the well-used one grandpa used to carry are often slip joint designs.
The clasp lock is a light-duty mechanism that works via a pin on the blade tang. The pin slides into a lock hole in the rocker arm or “clasp” to hold the blade open. To release, pull the ring and fold. Clasp locks date back centuries to Spain, the land of flamenco and running bulls.
The earliest Roman folding knives were friction folders. The user grips the handle, plus the extended tang, creating friction on the stop pin. This is a “non-locking folder,” bypassing bad knife laws that restrict carry of certain knife types. The most popular modern friction folder is the Svord brand from New Zealand.
Popularized by the iconic Buck 110 folding hunter, the back lock has a rocker arm that pivots on a center pin. When open, the lug connects with a notch in the blade tang and a tension bar keeps the lug in place. To close: push the rocker arm in to release the lug and fold blade.
Found on Italian stilettos, this lock is a rocker arm against a backstop. To close: a pivoting bolster releases the rocker arm. A firing button with a lug inserts into a detent hole to keep it closed. Press the button to release the lug and fire the torsion spring.
McHenry and Williams invented. Benchmade launched. It has a sliding lock that connects to an omega spring attached to the liner. The sliding lock presses into a backstop in the blade to secure the knife open and is a detent when it’s closed. You haven't felt joy until you get your hands on a buttery smooth AXIS lock. Sometimes it's all about the small things in life. Side note: a few years ago, the utility patent expired on the Axis lock, and the mechanism entered the public domain. Every company that uses it calls it a different name, but everybody knows they owe a little nod to Benchmade for the technology.
This proprietary Spyderco lock works like a liner lock on the back of the handle: a leaf spring is cut from the liner and engages in a blade tang cutout. A detent ball on the liner connects with a detent hole to keep the blade closed. Think of the compression lock like a reverse liner lock, but easier to fidget with and stronger overall. Is that the definition of "the best of both worlds?" You be the judge!