Knife Tangs Explained
By Gary Zinn
I have noticed that one of the most overlooked subjects regarding fixed blade knives is handle tangs. When a new model of knife is introduced, or when knives are reviewed, the promotional or critical focus is usually on the blade steel, pattern, size, handle material and shape. The tang is seldom even mentioned.
Yet, the tang is the frame or anchor around which a complete knife is built, so it invariably implies something about the characteristics of a knife. My purpose here is to clarify the distinctions among tang designs and discuss what they imply about the capability, performance and durability of knives. The tang even affects the choice and application of handle materials, which in turn affects ergonomics and aesthetics.
What is a tang?
Simply put, a tang is the portion of a knife that extends from the base of the sharpened blade into the handle. It is a continuation of the steel blank from which the blade is formed. All conventional knives, whether folders or fixed blades, have tangs.
Folding knife tangs are quite short, just long enough to provide for a pivot axle hole, plus a radius and shoulder for a back spring or latching mechanism to work against. Beyond that, there is not much to say about folding knife tangs that would be of general interest. Rather, I will focus on tangs for fixed blade knives, since that is where the important variations are found.
Fixed blade knife tangs fall into two basic categories, hidden tangs and full tangs. A hidden tang is sized and shaped so that, when handle material is added, the tang will be enclosed, or hidden, within the handle. By contrast, a full tang is formed to exactly match the profile of the finished handle. The handle of a full tang knife will normally be finished by securing pieces of handle material on both sides of the tang; these are called handle slabs, or scales. The tang is fully visible between the handle scales.
The case for full tangs
The full tang is widely used in both commercial and custom knives, because it is strong, simple and versatile. As the schematic below indicates, a typical full tang knife might have ten parts, including the blade with tang, handle slabs, cross pins, lanyard hole tube and front bolster/finger guard furniture (shown, but not labeled).
The Buck Model 113 Ranger Skinner, for instance, is built almost exactly as the schematic shows. However, a multitude of variations on this simple theme can be made by tweaking the handle profile, changing handle material or bolster furniture, or adding a rear bolster.
The Kershaw Model 1082 Field Knife is a commercial item that is even simpler. It contains five parts: the blade with tang, two G10 synthetic handle scales and two cross pins to secure the scales to the tang. This is a tough, no-frills working knife.
Further, the full tang concept lends itself to a skeletal handle (a.k.a., self handle), where the tang is the handle. The [http://www.chuckhawks.com/buck_135_knife.htm] Buck 135 PakLite Caper knife, with a skeletal tang/handle, is truly as simple as can be. Sometimes these handles will have an elastomeric coating, or they may come with or be amenable to a wrapping of paracord or a similar material over the handle. These additions are meant to improve an otherwise sketchy gripping area, while adding hardly any weight. The PakLite Caper with a 2-1/2 inch blade and 6-7/8 inch OAL, weighs just 1.1 ounces.
The rattail hidden tang design
The following schematic shows all the elements of a traditional hidden tang knife. Note that the tang is designed to run the full length of the handle and the width of the tang is significantly narrower than the width of the blade. This is called a rattail tang. It may also be called a full-length tang, but is not a full tang as described above.
The metal finger guard is slipped down the tang and rests on the shoulder formed where the blade width is reduced to the tang width. The handle material fits over the tang behind the guard and the pommel is attached to the end of the tang to keep everything together.
This is the best schematic of the design that I could find, but a couple of things it suggests are obsolete. First, it is indicated that the solid handle is secured and stabilized by cross pins that run through the tang. This is rarely seen nowadays, with epoxy adhesive commonly used to secure handle material to the tang, so that cross pins are not needed.
Second, the schematic suggests that the tang is rounded, threaded on the end and then the pommel is screwed onto it. This is seldom done, because a screwed-on pommel can easily loosen. Instead, pommels are usually secured via a cross pin that fits laterally through the pommel and a small hole in the end of the tang (the end is not rounded and threaded). Another approach is to not use a full pommel, but instead to crimp or peen a metal nut or disk (usually brass) onto the end of the tang. Helle does this throughout their line of rattail tang knives.
Are full tangs stronger than rattail tangs?
On this often argued subject, the short answer is "Yes" and the logic is obvious. Suppose we were to take two identical billets of a knife steel and mill a full tang knife blank from one and a rattail tang blank from the other. Then place the blades of the two blanks in a vise and apply equal pressure to the protruding tangs. The rattail tang would surely fail before the full tang.
However, this does not take the whole situation into account. Specifically, how does the addition of handle material affect the relative strengths of full tang and rattail tang knives? I have no experimental evidence on this, but logic tells me that the addition of handle scales to a full tang knife blank adds little to the strength of the knife. However, the material used to build a handle on a rattail tang adds strength. This is because the handle wraps completely around the tang, reinforcing it.
Consider the legendary KA-BAR USMC Fighting Knife. The original design, its variants and clones became fabled combat knifes during World War II, a reputation that survives to this day. This knife has a rattail tang with a steel finger guard and pinned-on steel pommel. The handle is a set of leather disks, slipped over the tang and securely glued and pressed together. (See "How KA-BAR Knives Are Made" on the KA-BAR website, which is an illustrated synopsis of how these knives are built.)
The KA-BAR is obviously strong and durable. It would never have become a legend if it had failed to perform under combat conditions. Although it almost certainly would not prove as strong as an otherwise identical full tang knife if both were subjected to controlled abuse-to-failure tests, this knife has proven its strength and durability in the most demanding real world laboratory: the battlefield. My take on the "which tang type is stronger and more durable" question is this: a full tang knife may be inherently stronger, but a well-made rattail tang knife is not far behind and is, literally, good enough for government work.
Another note on the subject of built-up handles on rattail tangs. Some really nice aesthetic effects can be achieved by combining different handle materials. For example, check out the Helle Odel, with a handle that combines curly birch, antler and leather. True eye candy.
Other hidden tangs
To review, a rattail tang extends the full length of the knife handle and will protrude a short distance behind. The end will be capped with a pommel, disk, or nut.
However, this is not the only widely used type of hidden tang. For instance, the Mora Bushcraft SRT knife uses a hidden tang that extends about three-fourths of the way (rather than all the way) through the handle. This is called a three-quarter tang.
The three-quarter tang is common in better quality, mass produced knives with injection molded thermoplastic handles. There are numerous examples on the market. Mora builds the Bushcraft SRT by forming the blade/tang unit and then using an injection molding process to add the handle. Simple, fast and economical once the cost of molding machinery and dies is amortized.
Totally hidden tangs are not just for molded synthetic handles; they can be used with solid handles, too. For instance, Helle makes a sturdy general purpose knife, called the Fjellbekk. This knife has a four inch, laminated stainless steel blade with a three-quarter tang. The solid walnut handle is 4-5/8 inches long. It has no additional parts.
How is a knife like this made? First, the tang will be shaped so that it narrows from front to back, instead of being parallel. A slot into which the tang will fit tightly is bored into the handle from the front. Epoxy is squirted into the slot, the tang is pressed into it, and it is done. Not surprisingly, this is called a push tang.
Short tangs and exposed partial tangs
Two miscellaneous things before I tie all of this together. First, what about short tangs? Defining a short tang as anything less than a half-tang, any knife intended for serious work should not have a short tang. A short tang is acceptable only for light duty knives, such as flatware, or for knives that are meant for display, rather than actual work.
Finally, there is a tang pattern that does not fit into any of the categories covered above. I call this an "exposed partial tang," because it is exposed in the top of the knife handle, but not in the bottom. Thus, it is neither a full nor hidden tang, as those were defined above. A current outdoor knife with this tang pattern is the Helle Temagami.
In the Temagami, the tang runs the full length of the solid wood handle. It fits into a groove rabbeted into the top of the solid wood handle, which is cross pinned through the tang. I have a Forschner brand butcher knife that has a three-quarter exposed partial tang. I have also seen exposed partial tangs in some custom knives. This is a legitimate working knife design, with inherent strength that likely falls between that of full and rattail tangs.
My main takeaway from this exercise is that the type of tang is an important factor in choosing a fixed blade knife that is best suited for a particular purpose. I came up with the following usage categories that imply appropriate tang types.
Super heavy duty: If I want the toughest knife possible (the kind that the bushcraft/survivor/tactical dudes drool over), I would confine my attention to full tang models. I would want a very tough steel, such as 1095 carbon, formed into a blade that is thick and wide relative to its length. I would favor bomb proof handle material, such as G10 or Micarta. Handle scale pins should be steel and I would not want the clutter of any add-on furniture. The ESEE-4 and -6 series knives are spot-on examples. I realize that the parameters I have set for this super knife eliminate many fine knives from consideration, including those of the Ka-Bar fighting knife type. However, this is where logic leads me. This is the sort of knife I would want if I knew I would need to hack through a light gauge steel door tomorrow. I own one beast knife that I bought on a whim over a decade ago. I have never used it, except to do some test cuts. Most of us do not need a knife this radical, but need and want are different things if one is into knives.
Heavy duty: The game changes if I take a step back from the toughest knife possible, focusing instead on as much knife as I am reasonably likely to use. Full tang models that are somewhat trimmer than the previous category are obviously still in play (e.g., larger hunting knives). Rattail tang knives join the party, including both hunting and Ka-Bar style knives. Steel can be either carbon or stainless, but should be of high quality. Handle materials can be a wide range of natural and synthetic materials, but should still be tough and durable.
My largest hunting knives fall into this category. I have two and both are built on rattail tangs. One is a [http://www.chuckhawks.com/buck_hunting_knives.html] Buck Pathfinder with a 5-inch blade, laminated wood handle, brass finger guard and cross pinned pommel. The other, a [http://www.chuckhawks.com/helle_symfoni_alden_knives.html] Helle Alden, has a 4-1/8 inch blade, solid hardwood handle, steel finger guard and brass tail nut on the tang.
I also consider knives with exposed partial tangs and the better hidden three-quarter tang knives to be heavy duty. Knives with sturdy three-quarter tangs, either push tangs with solid handles or handles injection molded with quality synthetics such as Kraton, can hold their own with comparable full or rattail tang knives.
Medium duty: This category includes knives that are typically somewhat shorter in blade length, lighter in profile and weight than heavy duty knives. These are the knives I most often carry for small game hunting, deer hunting and general outdoor use. All tang types except short tangs are potentially satisfactory.
My concept of a medium duty knife is one with a blade about 3-1/2 inches long, an OAL of eight inches and weighing less than five ounces. Currently, my two favorite knives that fit these specs are a Helle Symfoni and my John Hege custom knife. The first has a three-quarter push tang in a birch, antler and leather handle and the second has a full tang with bokote handle scales.
Beaters: Finally, I do not want to overlook what I think of as beater knives, i.e., inexpensive, but still capable, knives that I can abuse with impunity. Here are two that have hidden half or three quarter tangs in molded handles.
First, a Mora Companion that I use for rough work, even using it as a digging tool when I am gardening or landscaping. The Companion takes the abuse well and if I were to break or lose it the cost of replacement is quite low. I also have a Cold Steel Pendleton Lite Hunter that is part of my fishing tackle. With a molded polypropylene handle, a decent stainless steel blade and a Cordura nylon sheath it does not suffer unduly if it gets wet. It would not be painful to replace if I drop it in deep water.
Everyone should have a couple of beater knives. I have said that beater knives should be inexpensive, but do not confuse inexpensive with cheap. Cheap no-name knives typically feature inferior materials and shoddy fabrication. There are even rumors that such knives sometimes have tangs brazed onto the blades. Yuck! Do not buy junk knives and expect them to give satisfaction. There are inexpensive yet serviceable knives made by reputable firms, so there is no reason to do business with junk knife marketers.
When knives are discussed, the subject of tangs is not nearly as sexy as blade steel, pattern and size, or the latest handle material. I understand this. However, I hope that what I have covered here helps the reader appreciate that the tang is an important part of a knife. We should be aware that tang design influences the performance characteristics of a given knife and take that fact into account when we are evaluating knives for purchase and use.
Copyright 2015 by Gary Zinn and/or chuckhawks.com. All rights reserved.