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- What Are Diving Knives?
- Why Are They Important?
- Do I Need One?
- 5 Best Dive Knives And Dive Shears
- Things To Look For In A Dive Knife
We all hope that we never run into a diving related emergency, but unfortunately, it happens.
If you’re thinking about getting some safety equipment, you’re probably thinking…
Do I need a scuba diving knife – and which one should I get?!
We’ve got you sorted with a quick rundown of the importance of knives and some of the best scuba diving knives on the market in 2020!
What are dive knives and shears?
Scuba diving knives and shears are designed to be able to cut through anything which might entangle you underwater. This can include nets, fishing line, or even your own equipment.
You might be wondering how a dive knife is different from the kind in your kitchen drawer. Well first off, safety is a major issue – you don’t want sharp pointy objects anywhere near your air hoses which are keeping you alive.
Many dive knives have slightly blunted tips for this reason, though the blades are incredibly sharp and very sturdy. Another essential aspect is the resistance to salt corrosion, which would quickly destroy your average kitchen blade!
Let’s have a look at a few different types on offer:
Does what it says on the tin. These knives often have both smooth and serrated elements so they can be used in multiple ways.
It usually comes with a fitted sheath that can be strapped to the arm, leg or BCD.
Shears are more like scissors than a knife, though the blade is much sharper than your average pair of scissors and the mechanism is much more powerful to allow the cutting of straps, thick netting and even drysuits.
These tools are the most safety-conscious, as the blade is protected and it’s difficult to accidentally cut yourself or your life-saving air hoses. They’re also great for travel, as they are allowed into countries where carrying knives is prohibited.
Why Are They Important?
When divers think about emergencies, they usually think about things like out-of-gas situationsor getting stung by the wildlife, but many overlook the silent killer of the scuba world:
Entanglements can be deadly because you’re relying on the gas you have left in your tank, and your (hopefully very close by) buddy to keep you alive. A bad entanglement can result in an out of air scenario.
This scenario works both ways of course – if your buddy finds himself entangled in a ghost net, you’re going to wish you’d bought that knife!
You can also use knives to have a positive environmental impact. Encountering a turtle with a net around its neck is incredibly sad – and it’ll be even more heartbreaking if you don’t have a diving knife handy to help free it.
They can also be used to safely remove lines and nets from reefs without disrupting the coral.
A good scuba diver must be a jack-of-all-trades, and a good scuba diving knife allows him to be helpful in many different scenarios. In addition, some countries require divers to carry a knife as a safety precaution.
Do I Need One?
We all hope we’ll never have to use a dive knife.
But it’s undeniable that a good, reliable scuba diving knife or pair of diving shears is worth every penny spent.
You never know when you’ll encounter a scuba diving emergency, but having a great diving knife will mean you’re as prepared as possible.
It’ll also provide peace of mind for yourself and your dive buddy. This makes dive knives a basic safety choice. Carry more than one, and different types.
If you’re a beginner diver, this probably isn’t the first piece of equipment you should buy.
A well-fitting scuba mask or a vital dive computer should be your first stop. When you’re diving with an instructor or divemaster, feel free to check that they’re carrying a dive knife or shears, to put your mind at ease.
If you are diving frequently, a diving knife is essential. If you are leading your own dives with a buddy, or even by yourself, you should be carrying at least one back up too.
Which Type Should I Get?
Line cutters are the safest option and are often found unsheathed as the blade is protected. This is the best choice for those who travel a lot, especially into territories where knives are controlled.
They’re also a great choice for beginners who may feel nervous about carrying an exposed blade around scuba gear.
Knives are best for confident scuba divers and are the most versatile choice. Avoid big, Rambo-style sea hunter knives and opt for a short, sturdy knife with a variety of features.
Very long knives are harder to control and risk damaging your vital, and expensive, diving equipment.
Shears are a great back up choice – there’s a reason they are popular with EMTs and firefighters, they get the job done quickly and efficiently. Carrying a pair of diving shears as well as a knife is the combination of tools we recommend.
5 Best Dive Knives
Our best all-round selection is the Cressi Skorpion diving knife. The blade features smooth, serrated and line cutting elements, ensuring its versatility.
It is medium-sized, with a 4 ¾ inch blade. Both sides of the blade are easy to sharpen and its corrosion-resistant stainless steel construction makes it an excellent, reliable budget scuba knife.
It can also be purchased with a titanium blade, for only a small price increase. You have a choice of either a sharp or blunt tip.
This lightweight diving knife comes with a snugly fitting sheath, which has a locking mechanism that you can release with one hand.
The handle is molded rubber with a tank banging tip and is a suitable size for both men and women. Two long rubber straps mean it can be attached to the arm or leg.
The Scubapro Mako is a small, lightweight diving knife, perfect for traveling.
Its blade is quite small but is completely fit for purpose, with a wickedly sharp, corrosion-resistant titanium blade. Titanium ensures it is extremely resistant to rust as well as being incredibly strong and light.
It features both smooth and serrated edges with a line cutting notch. The tip of the blade is sharp but features a blunt edge too for versatility of use.
It is a very compact model and a thin handle means it sits in a very low profile against the leg or BCD strap.
Its sheath has a secure push-button release for safety and easily adjustable straps.
The handle is suitable for both left and right-handed people and the tip of the handle has dual purpose as a metal tank banger and a bottle opener – essential, obviously.
The Scubapro Mako is a popular and reliable diving knife in the scuba community. The only downside is the slightly more expensive cost, but you can be sure you are getting reliability for your buck!
Promate’s answer to the Cressi Skorpion is this compact, titanium diving knife.
The 4 ⅜ blade has contrasting edges, with smooth and serrated sides as well as a line-cutting notch and choices of blunt or sharp tips.
Though the teeth of the serrations are not as pronounced as other models, it does the job well. The full-tang, titanium construction ensures it is super lightweight and strong, with excellent resistance to corrosion.
The 5-inch handle is easy-to-grip molded rubber so it won’t slip. It also features a hammer at the end to attract attention should you need it.
The sheath and straps allow this diving knife to be strapped securely to the leg. The handle also comes in a selection of vibrant colors, ideal for spotting underwater.
The Atomic Aquatics Titanium Ti6 is a versatile and resilient knife The blade is fully titanium and combines great strength with low weight and corrosion resistance.
It features a dual-edged blade with both serrated and smooth sides and a line cutting notch. You can choose between pointed and blunt tip options, depending on preference.
The handle is comfortable to grip, ergonomically designed to fit your hand with a titanium banger on the end.
The sheath is lightweight and features a push-button for a quick release, with simple-to-use leg straps.
If you don’t already own a cutting tool for scuba diving, the EEZYCUT Trilobite is a great place to start.
It’s very affordable and can slice through almost anything you’ll encounter when scuba diving.
Whilst its backward-facing, stainless steel blade poses no danger to fingers or hoses, it is designed to slice easily through fishing line, nets and scuba webbing – even cutting through drysuit if required.
It can’t cut anything thicker than 0.47 inches in thickness though, and it won’t be much use in difficult environments like kelp forests.
Here’s a great video demonstrating what the Trilobite can slice through:
It is also a great backup option for those that already have a knife. Due to the compact size and velcro attachment, it is easy to carry but might just help you out of a sticky spot!
It also comes in a variety of bright colors, ideal for spotting underwater. It is possible to fully disassemble the Trilobite and it comes with two replacement blades.
Whilst you can get many different types of diving shears, some which function as both knives and shears, the most effective and best scuba diving shears are actually simple EMT Trauma Shearsused by emergency responders around the world.
This strong, scissor-like tool will cut through nearly anything and comes in conveniently sized nylon pouches. The loops and straps mean it can be threaded onto a waistband or strap, looped through rings or stored in a pocket.
Caring for these shears is especially important as it is easy for saltwater to get stuck in the mechanism and cause rust and corrosion. Smooth movement is the key to shears, so be sure to rinse and dry them thoroughly after each use and consider using protective oil. Even so, expect to have to replace these more often than dive knives.
Things To Look For In A Dive Knife
Sharp tips are favored by fishermen and more experienced divers. They can be useful but can cause injuries and damage to equipment in inexperienced hands. Blunt tips are good for beginners and are more useful as they can be used for digging or prying. They are safer to handle around hoses too.
Bigger isn’t always better… Most dive knives range from 3 to 6 inches though many find smaller knives optimal as they are easier to carry and store without added bulk as well as being easier to control underwater.
There are two types of blade edge – serrated and smooth. The ideal dive knife should have both for versatility.
The straighter edge is useful for cutting plastics and lines whilst the serrated is suited to sawing through natural-based materials like rope and kelp fronds. If you have to choose, the serrated edge is more useful.
Other useful additions to the blade include line cutting notches which can slice through lines with little to no effort.
Your average kitchen knife will quickly rust and corrode when exposed to the harsh ocean environment. The best material for your dive knife blade is either titanium or stainless steel.
Stainless steel will require regular sharpening and maintenance with oil to prevent corrosion. Titanium blades are lighter, stronger and require less maintenance and sharpening, but they are more expensive and harder to sharpen.
Metal handles are convenient for banging on your tank to get your buddy’s attention but are slippery and difficult to hold.
A well-designed ergonomic handle should feel comfortable in your hand so you are less likely to slip or drop it. Some also have added features like tank bangers or bottle openers.
Thinking about the color of a diving knife might seem a little superficial but it’s an important consideration.
Whilst slick, black models look smart and are ideal for hunters (they blend in more), bright colors ensure that your knife can be seen when it’s most needed.
This could be when your buddy needs to grab it quickly, or when you’ve just dropped it on the seabed…
This is the way you will attach your dive knife or shears to your gear. There are several options:
- BCD/Hose Mounted – A secure way to attach it to your gear, easy to access and not easily forgotten. Remember to clean and dry regularly, though.
- Leg Mounted – These knives come with straps to attach to your calf or thigh. It has the benefit of quick access but it can get caught on things or fall out if it isn’t secure in the sheath. Yes, ok, and you’ll feel like Lara Croft.
- Foldable knives – These can be stored in the BCD pocket, making them a great, safety-conscious choice. They can also be attached using a bungee or strap.
What are the advantages of a good knife?
>Reliability is the key here. You never know when you’ll need your knife so knowing you can rely on it when you need it is vital.
The best scuba diving knives are also strong and sharp and maintain their edge over time. Easy handling is also a key aspect of a good diving knife.
Getting your blade out quickly and knowing you’ll have a good grip when you do can be vitally important in time-sensitive situations.
How do I look after my dive knife?
It is important to rinse your knife with fresh water if you have been diving in a saltwater environment. Ensure it is fully dry before storing it in its sheath. If there is dirt on the blade or handle, use a mild soap to clean it before drying.
Sharpen the knife as needed, as you would a kitchen knife, by using a sharpening stone, steel or worktop easy sharpener like this one>.
For long term storage, oiling the blade helps prevent rust. There are specific dive knife oils, but a thin layer of regular household oil like olive or canola will achieve a similar effect – preventing moisture from reaching the metal.
Is Titanium Or Stainless Steel Better?
Titanium blades are less prone to rust than their stainless steel cousins. As a result, they require less maintenance and are lighter and stronger than stainless steel.
On the defense of stainless steel, it is also rust-resistant with the proper care and they are much cheaper.
Whilst we hope you never have to use one, diving knives have been around for as long as scuba diving itself, and for good reason. We’ve narrowed down the best tools for the job so you can dive with reassurance and safety.
Consider getting one or several of the cutting tools we discussed in this article to help protect yourself from a tragic entanglement.