Reviewing the Best Dive Knife of 2021
Promate Scuba Diving 5” Stainless Steel Knife
Bahia Dive Supply Stainless Steel Dive Knife
Aqua Lung Argonaut Titanium Diving Knife
Kyle W Updated on January 7, 2021.by
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A diver will always need to carry a dive knife when diving. A dive knife will help you or a marine animal get out of an emergency situation. Dive knives can quickly go from a handy tool to a lifesaving tool in just a matter of seconds, which is why you should always carry a dive knife when diving.
There are many styles, sizes, and shapes of dive knives today. It can be difficult to decide which one is the best, and that’s exactly what we have come to discuss today.
We have compiled a list of the best dive knives along with some helpful information that will make your dive knife decision the easiest one yet.
Why You Need a Dive Knife
As a diver, you know that what lies beneath the surface can be unpredictable. There can be fishing nets, lines, ropes, wires, or other entanglements that can trap you, your fellow diver, or other marine life. These entanglements can quickly become dangerous if you are unable to escape. Without a dive knife, you or the marine life may be unable to become disentangled from the net or ropes.
Marine life is unpredictable and can show up completely unannounced or uninvited. A dive knife can mean the difference in life and death if you are attacked by a marine predator. You may not have to kill the animal, but instead, injure it to scare it away, and the dive knife will allow you to do this.
In addition to becoming disentangled, you can also use a dive knife to anchor yourself during strong currents or undertow.
All of these scenarios make the dive knife a potentially life-saving tool that you should have while diving at all times.
How to Choose the Best Dive Knife
Dive knives can vary based on blade type, size, material, and attachment features. Let’s break each of these features down to get a better understanding of them. This will help you know which is the best dive knife for you.
Blade Edge & Tip
The blade edge can be serrated or plain, and the tip can be blunt or sharp. The combinations are endless.
- Serrated edge – the edge of the blade with “teeth” or grooves. Serrated edges can easily cut through hard, tough surfaces.
- Plain edge – the edge of the blade that is smooth and sharp with no teeth or grooves. Plain edge blades are recommended for clean cuts, like skinning an animal or peeling fruit.
- Blunt tip – the tip of the knife is cut straight across and not sharp. This prevents the wetsuit from being cut by the sharp blade tip of the knife.
- Sharp tip – the tip of the knife is sharp like a spear and can be used for stabbing.
Serrated edge knives are highly recommended for diving as they will be able to cut through tough surfaces, like ropes, nets, or other material; however, many dive knives have a serrated edge on one side and a plain edge on the other, which gives you the best of both worlds.
Dive knives with a serrated edge on one side and a plain edge on the other side with a blunt tip will be the safest and most effective dive knife.
As you will be using your dive knife underwater, it will need to be easily opened and wielded. A small blade will be easier to maneuver underwater than a large blade.
The ideal blade size for a dive knife should be between 3 to 5 inches. Blades that are bigger than 5 inches can be difficult and dangerous to operate underwater, and blades that are 3 inches or less are likely not large enough to be effective underwater.
For this reason, you will want a dive knife blade larger than 3 inches but less than 5 inches to be the most effective and easy to use.
Sand and saltwater will easily corrode and rust the knife blade. For this reason, the knife blade should be able to withstand frequent submersion in saltwater without rusting quickly. The best material to resist rust and corrosion will be stainless steel and titanium.
Stainless steel is less corrosion and rust-resistant than titanium. Stainless steel will require frequent cleaning after each dive as the saltwater and sand can quickly corrode and dull the blade.
Titanium is more resistant to rust, corrosion, and dulling. Titanium might cost more upfront, but the reward will be worth it.
Foldable or Fixed?
The dive knife can be foldable or fixed, and there are benefits to both.
Fixed knives are essentially quick and easy to use. Simply remove the fixed dive knife from the sheath, and it is ready to use. It’s a relatively quick and simple process.
Foldable knives will require time and effort to open the knife; however, they are typically smaller than fixed knives, which allows them to be more easily stored. Foldable knives are also considered the safer option of dive knives because they significantly reduce the chance of the knife inadvertently coming unsheathed and causing injury.
However, both foldable and fixed dive knives are sufficient and effective dive knives, and both have their own respective benefits.
The dive knife will need to be attached to you in some way. This could be through straps, a tether, a lanyard, or a pocket clip.
The best method for attaching the dive knife to you is with straps. There will typically be two straps connected to the sheath of the knife, one located on the blade of the knife and one located at the handle. This will keep the sheath evenly strapped to your leg for quick and easy access.
The knife can also be attached to you via a lanyard or tether. This will keep the lanyard connected to you by a rope or string so that it doesn’t sink to the seabed without realizing it.
Another feature the knife may have is a locking mechanism that will keep the knife securely in the sheath. This is important as it will prevent the knife from inadvertently falling out of the sheath while diving.
Caring for and Maintaining Your Dive Knife
To get the most out of your dive knife, you will need to take care of it with routine and frequent maintenance, sharpening, and care.
Knives made of stainless steel will need frequent cleaning. To do this, you will need to remove the knife from the saltwater and immediately rinse it with clean, fresh water. Allow the knife blade to dry completely before storing it in its protective sheath.
Should your knife have any dirt or grime on the blade or handle, you can take some gentle soapy water to clean away the dirt and grime. Then you will rinse the soap completely and allow the knife to air dry completely before placing it into its protective sheath.
Mineral oil is recommended for dive knives that won’t be used for a lengthy amount of time. Mineral oil will help preserve the blade as well as protect it. Only apply a thin amount of oil to the blade before placing it into the sheath for storage.
When you are diving, you will need a quality dive knife. A dive knife can help you become disentangled from nets, rope, wires, or other underwater lines that can easily cause you to become entrapped. A dive knife that has a serrated blade edge can quickly and effectively cut through any of these rough materials so that you can free yourself, a fellow diver, or other marine animals.
You should try to find a dive knife that has a serrated edge on one side of the blade. This will help you be able to cut through different types of materials underwater. The other edge of the blade can be plain or have a line cutter; however, the greatest benefit of a dive knife will come from the serrated edge.
No matter what type of dive knife you choose, it is essential that you keep the knife well-maintained. Maintaining your dive knife regularly will ensure the dive knife lasts as long as possible without prematurely deteriorating. Simply rinse the dive knife off with fresh water and soap, if necessary, to remove salt, sand, and buildups of dirt.