A Guide to Different Types of OTF Knife Handles
Not all OTF knives are created equal. Of course, even someone entirely new to the category can tell that just by browsing OTF blade styles and lengths and finishes online. But occasionally big pricing difference can puzzle people who consider themselves fans of OTF designs but who don’t understand all of the intricacies of their construction. We often hear some variation on the following question: “Why does this knife cost so much more than this identical one we found somewhere else?”
That’s a good thing to ask. Most of the time when you find such a disparity, though, the knives are anything but the same. Changes in construction and different choices in materials can lead to radically different costs for consumers and knives that perform very differently despite appearing quite similar. One of the most consequential choices that a producer can make may surprise you since it doesn’t involve the blade — it’s the handle.
In this article, we’ll talk about the main materials used for OTF knife handles and how they impact knife cost and performance. In addition, we’ll also consider various decorative and practical coverings that get placed over knife handles.
The Main Materials Used in Knife Handles
If you search for “knife handle materials” online, you’ll discover a bevy of options. That makes sense given that many designs are simple and stable, able to accept options that lack rigidity or significant impact resistance. The same can’t be said for OTF knives. Due to their inherent complexity, they require handles that can protect their inner workings from drops or impacts. This means handles for OTF knives have fewer options — two, in actuality: zinc alloy and aluminum. Both offer protection and facilitate OTF functionality, but they have very different processing methods, physical characteristics, and costs.
Zinc Alloy Handles
Zinc is a commonly used element in many industrial and manufacturing processes, not the least of which is its relatively low cost. Producers looking to produce items requiring the functionality of, say, stainless steel or some similar metal may select a zinc alloy since it’s generally significantly less expensive. However, note that we used the word “alloy”; on its own, zinc is brittle, so it needs to be mixed with other metals. (One candidate is, appropriately enough for our topic, aluminum.)
As an alloy, zinc proves quite strong and resists corrosion or rusting, which is why you often find it as a coating on more reactive metals. It has a low melting point, meaning that manufacturing processes involve die casting (i.e., liquefaction and high-pressure injection into a prepared mold). Die casting offers certain advantages such the ability to cast end products with thinner tolerances, which also lowers costs. But zinc alloys are significantly heavier even with thinner construction, making for a weightier knife overall. It also cannot be anodized — but we’ll discuss that more as we discuss aluminum in the next section.
Though you won’t hear them referred to as such, aluminum knife handles are also alloys just like those made from zinc. The reason why is that aluminum is quite soft and stretchable in its natural state, characteristics that don’t make for durability. However, that changes once manufacturers add in other metals, most typically copper, manganese, silicon, magnesium, and/or zinc itself. Aluminum alloys generally outperform zinc alloys on every measure of strength, including tensile strength, yield strength, and hardness. (Note that this may vary with certain very specific kinds of alloys.)
When it comes to density, aluminum also outperforms zinc — in the opposite direction. Aluminum alloy is about half as dense as zinc, making it much, much lighter. This is the primary reason why many prefer aluminum over zinc from a performance perspective. Another is the fact that you can anodize aluminum, granting it a hard, protective layer by running the aluminum through an acid electrolyte bath with current passing through it. Anodizing also can lead to color or pattern changes, making it an attractive decorative option.
However, aluminum does possess some drawbacks. It’s susceptible to dings and scratches. It conducts ambient temperatures well, meaning it can get uncomfortably cold in cooler climates. It may prove hard to hold if not textured or covered (more on that below). And it’s significantly more expensive than zinc alloys.
In short, aluminum alloys enjoy greater strength, lighter weights, and more decorative options, but you can expect to pay for it.
Decorative Materials and Functional Coatings Used with OTF Handles
While most OTF knives have handles made of zinc alloy or aluminum, they may also feature additional layers or coatings designed to make them easier to use or to give them a specific look. Some of what you’ll find in the OTF knife market includes …
Employed in many folding knives, steel provides excellent dent, scratch, and stain resistance at the expense of weight. While some OTF knives use it, it’s more often combined with other materials in a handle.
Super light, tough, and non-conductive, titanium can prove expensive. It’s most often used as a coating or with knife elements such as clips.
This catch-all term for material composed of woven carbon strands, carbon fiber usually weighs little and exhibits not-insignificant brittleness, although it’s quality often varies. While you’ll sometimes find it serving as the handle for a folding knife, it it’s more often used as textured panels on OTF knives.
G10 is a composite laminate is easy to grip and features many patterns and colors, but it’s vulnerable to impacts and not of uniformly excellent quality.
Acrylic, Grivory, Micarta, VALOX, and other synthetic thermoplastics sometimes find use as decorative or functional facades on OTF knives.
A kind of ceramic coating, Cerakote can add color and designs to both knife blades and handles.
Rubber and similar rubberized materials are generally employed solely to improve the handling of an OTF knife. They’re prone to degrade over time or when exposed to the elements.