Shu Review Part 3
The Shu locks firmly using a button lock with the button itself protruding unobtrusively from handle's show side and its mechanics hidden away inside the handle. This is my first knife with a button lock and I am very impressing with its strength as a lock and ease of operation. The detent is firm and appears to be independent of the locking mechanism as evidenced by my observation that the button moves only when locking open but not upon shutting; the author of the Edge Observer blog came to the same conclusion
in his review of the Ryo which as mentioned earlier also has a button lock.
In the first picture you can see the knife in the closed position with the button depressed. It seems to me that were the detent a function of the locking mechanism the button would return to its outward locked position. Take this with the same grain of salt you would any amateur's opinion.
The important matter is that both the lock and the detent work and work well. When open there is no blade play at all in any direction once the lock is engaged which it does with an authoritative click. If covert missions are you thing I do not recommend this knife. The lock is disengaged by depressing the button located a short distance from the thumbs in-use-position on the spine of the handle or blade. That much should be obvious.
The knife does not fall shut which presents no concern for me and detent clicks into place upon full closure and holds the blade firmly and securely within the handle. As the knife has a tip-up pocket clip–should you opt to use it–these is little chance that the knife will fall open while riding in you pocket. This is apparently accomplished by means of ridge just inside the handle from the choil visible in the photo below.
The detent is easily overcome using the dual thumbstubs. Comfortable on the thumb and at an effective distance from the pivot I have no problem whatsoever opening this knife smoothly. It should be noted that the knife does not swing open once the detent mechanism has been disengaged as is the case on a knife with an Axis Lock and requires a consistent sweeping motion with your thumb until locking in the open position not unlike a Sebenza, Mnandi or a non-flipping Emerson. The same is true when closing the knife.
While "spine-wacking" may have become the practice of some it is overkill for the intended use of a folding pocket knife. However, I like to "spine-tap" a new knife against my palm or the arm of an upholstered chair to see if there is any movement or shifting as might occur in a liner or frame-lock. There is no movement or shifting whatsoever in the blade itself or button when "spine-tapped" against my palm.
All of my locking knives are either liner-locks, frame-locks or some adaptation of one or the other such as the liner-less tab-lock on the Shirogorov Sigma or Hoback MK Ultra save for one compression lock, the Lil' Native. Each knife locks securely with no complaint from me but even on the best frame or liner-lock the lock-will slide–perhaps only slightly along the tang toward the opposite handle scale. This presents no weakness in my opinion and could even be construed as an asset: the harder you use it the harder it locks. However frivolous my spine-tap may seem to the reader I'm curious as to the interaction between the tang and the lock-bar and not at all "testing" for lock failure. The button lock as implemented on the Shu shows no such shift or movement. I have taken apart most of the knives I own for the purpose of maintenance with curiosity as an ulterior motive but I am hesitant or disassemble this knife without need as I am sure the button lock is more complex than a frame or liner-lock. And, springs make me nervous ever since taking apart a Benchmade Valet and struggling briefly to refit the Omega Spring properly.