What Is a Dive Knife and Do I Need One?

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What is a dive knife and what is it for?

A dive knife is a general tool that scuba divers use to cut fishing lines that have become entangled around marine life. It is significantly valuable during wreck diving, where encounters with tangled ropes and underwater plants are common and requires prompt release.

Contrary to what most people think, scuba diving knives are never used as a weapon to harm the underwater environment. But rather, they are designed for multiple purposes, offering scuba divers a useful tool to help manage underwater activities and emergency situations with care and safety. Furthermore, dive knives are also used to knock on tanks to get a buddy’s attention.

What are dive knives made from?

Most dive knives today are primarily made of two materials - titanium and stainless steel. Titanium dive knives offer superior corrosion resistance but come with a higher price compared to stainless steel. On the other hand, stainless steel dive knives offer a strong, reliable, and cost-effective option that is suitable for general-purpose use.

While stainless steel dive knives are known for their ease of sharpening, they require more regular maintenance to prevent rusting. In addition, they can also weigh up to twice as much as their titanium counterparts.

Types of Diving Knives

Depending on the type of diving and desired performance, there are different types of blades and dive knife that are best suited to various diving activities.

Leaf Shaped

Leaf-shaped dive knives are often characterised by their wide design, featuring two convex edges that are not symmetrical. These blades typically have a pointed tip and curved edges that provide long cutting shapes and surfaces that make a sturdy blade structure.

Sheepfoot

Sheepfoot blades have a rounded, blunt tip and a straight cutting edge that can either have a smooth or serrated edge. The rounded tip serves to prevent accidental cuts or punctures that are especially useful when working in confined spaces.

Drop Pointed Tip

Drop-point dive knives feature a spine, typically unsharpened, that follows a gentle convex arc down to the point. These blades boast a long cutting edge and a strong tip, though they might not be the most suitable for piercing.

Clip Pointed Tip

Clip-pointed tip dive knives feature a design where a significant portion of the unsharpened back is trimmed or "clipped" off. This unique shape enhances their piercing capability and creates a long, curved cutting edge.

Spearfishing Diving Knives

Spearfishing diving knives are commonly designed like a dagger, featuring a pointed tip that is ideal for spearing fish. These dive knives usually have a smooth, sharpened blade for slicing fish and a serrated edge to effortlessly cut through ropes.

Pocket Scuba Diving Knives

Pocket scuba dive knives are small and compact. They are specifically designed to fit conveniently into a BCD (Buoyancy Control Device) pocket or hang from a weight belt. Typically, they have a razor-type blade, which can be folded for added safety and compactness.

Fixed-blade

Fixed-bladed dive knives come with a fixed blade and handle. They are usually designed with larger blades and have a longer lifespan than other types of dive knives.

Dive Saws

Dive saws are specialised tools that feature a serrated edge, designed for cutting through tough materials like coral reefs or submerged debris.

BC Knives

BC knives are specifically designed with a compact feature, a blunt tip and a line cutter. Unlike spearfishing knives, scuba divers do not need a pointed tip for fish dispatching. Instead, these dive knives have specialised edges and a BCD mounting system that allows them to attach to the BCD.

Line Cutter

The line cutter is a type of cutting device that every diver should have. Designed to have a blade that is sharper than a regular diving knife, line cutters use a 420 surgical-grade stainless steel blade, renowned for its ability to effortlessly cut through the braided line, monofilament, and any other entangled fishing line.



Which factors to consider when choosing a dive knife?

Here are some key factors to consider to ensure you're choosing the right dive knife for your needs.

• Size

Dive knives come in various sizes. Whether you want it strapped to your lower leg or mounted on a BCD pocket, or secured to an HP hose, the blade length and the size of your dive knife will depend on where you would want them placed.



• Material

Stainless steel diving knife is a versatile tool that is used not only in scuba diving but in many outdoor applications. They are made with corrosion-resistant, high-grade stainless steel for a high level of durability and strength.

The Titanium diving knife is made from hardened titanium for complete corrosion resistance. It is lightweight but extremely strong, ensuring it maintains a sharp edge over long salt water dives.

• Blade Style

Diving knives with serrated edges are designed for cutting through strong materials like ropes and nets. On the other hand, dive knives with straight edges are better suited for precise, controlled cuts.

• Mounting Options

There are different mounting options to choose from allowing you to mount your diving knife on a leg strap, attached on a weight belt, or carried in a sheath.

What is the best dive knife?

At Dive Near Me, we offer quality products made from only the highest-grade materials. Whether you’re looking for a knife with a serrated edge or one with a straight edge, Dive Near Me has you covered. We have a wide selection of knives that are designed for deep-water diving environments.

Ocean Pro Shuka AB Knife Yellow

An ideal knife for abalones, boasting a 14cm stainless steel blade with a line cutter and hammer end. This knife features a secure lock sheath and comes with convenient leg straps.

Ocean Hunter Assassin Knife

A compact knife with a 9cm blade ending in a sharp stiletto point and a 35mm serrated section. The handle has rubber straps for added convenience and is equipped with a secure squeeze lock for quick release and effortless one-handed operation.

Ocean Hunter Hali Knife

An ultimate all-rounder, combining strength, sharpness, and a smooth cutting blade. The 11cm stainless steel blade is coated in black chromium, minimising the risk of rusting. Its ergonomically shaped handle ensures a comfortable grip and comes with a strong quick release sheath and convenient rubber leg straps.

Ocean Hunter Shadow Knife

Designed with a sleek and low-profile look, this knife features a 9cm serrated blade with a line cutter. It also comes with a webbing sheath and arm straps for easy and secure carrying.

Ocean Pro Komodo Knife

An all-around 14cm stainless steel blade with serrated edges and a line cutter, this knife boasts a hammer end for added versatility. The knife's ergonomic handle ensures effortless use, and the locking sheath provides secure storage. Additionally, leg straps are included for convenient carrying.

Ocean Hunter Redback Knife

One-piece stainless steel knife that stands out as the most rust-resistant in its class. With an 11cm blade featuring a 40mm serrated blade ending in a stiletto point, it offers exceptional performance. The knife also includes a quick-release sheath and leg straps for easy accessibility.

Ocean Pro Line Cutter

Made from marine-grade stainless steel, this knife's blade effortlessly cuts through lines with ease. Thanks to its design, the blade can be easily removed for cleaning or replacement and comes with a secure velcro sheath for safe storage.

Rob Allen Dentex Knife

Crafted from high-quality Japanese stainless steel, this knife is versatile enough to be worn on either the arm or leg. With a stiletto tip, sturdy spine, and single-piece construction, it proves itself a reliable tool for dispatching your catch.

The blade is easy to sharpen, maintains a sharp edge, and boasts excellent corrosion resistance due to its low carbon content. Additionally, the sheath securely holds the knife with friction when not in use, offering two strap options for versatile wear.

Salvimar Ares Knife

A unique Tanto blade, known for its exceptional sharpness and serrated edges for cutting lines. With a full tank construction, the blade is crafted from rust-resistant stainless steel. Its full tang design comes with removable sides allowing you easy cleaning and maintenance. Additionally, the knife includes a low-profile sheath that can be attached to your weight belt.

Cressi Alligator Scissors/Knife

Made from high-strength durable stainless steel, this knife serves a dual purpose as both scissors and a knife. It also features a notch that can be used as a line cutter.



Cressi BC Rescue Knife

Do you put a dive knife on the inside or outside of your leg?

There are several popular methods for carrying dive knives: strapping them to your leg, attaching them to your Buoyancy Control (BC), or hooking them onto your inflator hose. In most cases, a large dive knife is worn on the outside of your shin or thigh. On the other hand, a medium-sized dive knife is usually worn on the side of a BC pocket.

However, if you prefer to place your dive knife on your leg while diving, consider placing it inside your ankle. This placement reduces the likelihood of entanglement compared to other positions.



Should you dive with a knife?

A dive knife is not a mandatory gear for scuba divers. However, having one can be beneficial especially for safety and during emergencies. Since dive knives are specifically designed for underwater purposes, there are several compelling reasons to include them in your diving kit. With the help of a dive knife, you and your fellow divers can quickly release underwater in case of entanglement from lines, ropes, or nets.



Takeaway

Dive knives can make a great addition to any scuba diver's gear. Not only are they useful in disentangling lines and nets, but they can also come in handy during emergency situations that demand quick action.

However, before choosing a dive knife, it's essential to consider the key factors mentioned above to find one that suits your needs and preferences. Safety and proper training are also crucial to ensure that the knife is used effectively and responsibly during dives and further avoid any unwanted underwater incidents.

Whether you're an experienced diver or a beginner, the right dive knife can make a big difference in your safety and comfort underwater. At Dive Near Me, we're here to assist you in finding the best dive knife that matches your needs and budget, ensuring you get the most out of your diving experience.