Knives and knife steels
© Lincoln’s Tool Chest
From the time I got my first Swiss Army pocket knife as a child, I have had always had somewhat of a knife obsession. At that age, I had no knowledge that there were different types of knife steels, handle material, tangs, or internal components. Other than the outside appearance, the ten dollar pocket knife was the same to me as the forty five dollar one. As I grew older I learned that not only do different knife brands and designs look different on the outside, they can also have significant differences in both their make-up and construction.
Blade Steels: Topping the list of most knife makers and enthusiasts is blade steel. It would be impossible to calculate how much time and money has gone into developing better blade steel and rightfully so, it’s the most important part of the knife! Because of the fact that there are so many types of knife steels and one could make an entire article out of each type, I am just going to list the popular ones in three categories; Exotic Steels, Adequate Steels, Budget Steels. It should be noted, however, that a lot of the properties of the blade come not only from the type of steel used, but also from the heat treatment the steel has been given. The heat treatment of the steel can be just as important as the steel itself.
Exotic Steels: These are high end super steels that have been developed for certain applications, including edge retention, durability or corrosion resistance. These steels are costly to produce and are therefore usually only available on expensive knives. Steels such as CPM REX-121, CPM S-35VN, SPM-S30V, S110V and 154CM are just a few of the common ones. A lot of exotic steels tend be tied to and developed for certain knife manufacturers.
Adequate Steels: Purchasing a knife with one of these steels more than likely offers the best value in a knife purchase. They will hold an edge for a decent amount of time while not being too difficult to sharpen. Steels in this category are: VG-10, Sandvik 14C28N, D2 Tool Steel, 440C, 1095, 8CR13MOV, 420HC and AUS 8.
Budget Steels: These steels are usually found in low cost knives. Edge retention and longevity are not what these knives are designed for. However, since the steels are on the softer side, they may stand up to more abuse without actually breaking. This category of steels includes 440A, 440B, 420J2, AUS6
Handle Material – While knives are still available with handle material such as leather, wood, stag, bone, steel and plastic, new technologies and manufacturing processes today allow companies to offer more exotic handle materials such as aluminum, titanium, carbon fiber, G10, and FRN:
Titanium: Although more expensive to produce and slightly heavier than aluminum, titanium is stronger and more durable. Titanium also has a low thermal conductivity, so unlike other metals, it will not feel cold upon contact with skin. Just like aluminum, titanium handles can be anodized and may be slippery if not textured.
Carbon Fiber: Very strong and very lightweight, carbon fiber is a blend of carbon filaments bound together with resin. While the tensile strength of carbon fiber can vary according to its manufacturing process, it is generally stronger than both steel and aluminum. Carbon fiber can be brittle and may not have the best impact resistance. Like the twom materials listed above, it can also be slippery if the handles are machined smooth.
G10: Made from a mixture of fiberglass cloth layers and epoxy resin, G10 was initially developed for use as circuit boards. Cheaper to make than carbon fiber, G10 can be made in almost any color and is impervious to most chemicals. While G10 does not have the best impact resistance, in my experience the material is very slip resistant, even when not texturized. This is my favorite handle material.
FRN/GRN: Fiber reinforced nylon or glass reinforced nylon is a high strength plastic. Lightweight, flexible and strong, this handle material is very impact resistant. The main complaint about this material is that it feels cheap in the hand. FRN, while not quite as slip resistant as G10, is still somewhat slip resistant in the hand.
Tang (Fixed Knives): The tang of a knife is the portion of metal that extends from the blade into the handle. While there are many different varieties the simplest versions are:
Washers and Bearings (Folding Knives): Again, in today’s world the internal construction of folding knives can vary greatly. Most folding knives come with bushings, which may be made out of steel, phosphor bronze, Teflon. Other more exotic knives my come with caged bearings instead of washers for a smoother operation. While bearings definitely make the action of the knife smoother, they will more than likely require maintenance at some point, where a bushing may not. An internet search will reveal that there are many opinions on exactly which bushing or bearing is best.
Lock Types (Folding Knives): Growing up, it seemed that there was one main design for keeping a knife locked open and that was the lock back version. Today, knife lock mechanisms have expanded to quite a few variations:
Lock Back: This is the classic design where the lock is on the spine of the knife. When the knife is opened, the lock engages, trapping the blade in the open position until the lever on the back is pushed. While this is a very strong lock, the main disadvantage it has is that it usually requires two hands to close the blade.
Liner Lock: This is probably the most common lock available on knives today. On this type of lock, the liner on the inside of the knife handle actually springs out and wedges itself against the bottom of the blade once opened. To close the knife one simply has to push the liner out of the way and the blade can be returned to its place in the handle. One disadvantage is if you are gripping the knife hard and twisting, there is a chance you may accidentally pull the liner away from the blade allowing the blade to close. The strength of this lock can also vary depending on the size of the liner used.
Frame Lock: This lock works in the same manner as the liner lock, with the exception that the entire frame moves to engage the bottom of the blade. Since this lock utilizes the entire frame, they are usually stronger than a liner lock. Also, having the frame engaged makes it less likely for the lock to fail when twisting the knife as your grip puts pressure on the frame helping to secure the lock in place.
If you are new to the knife world, the above information should be a good starting point. As you can see, there are quite a lot of options depending on what you are looking for. Consider this a first lesson to help get you started…