A dive knife is a must-have safety accessory for spearfishing and diving, but it can come very useful, in certain cases life-saving while freediving as well. This article explains why and how to carry this piece of gear and features the most recommended models that freedivers should use.
Is using a dive knife necessary?
If you just started diving and are in the process of learning how to use your equipment, carrying a dive knife is not recommended. Until you are not fully comfortable in the water and with your gear, you can easily hurt yourself and others if an emergency situation occurs. But once you feel yourself confident and start spending more time in open water, a knife comes very handy in different types of situations.
8 reasons why you should carry knife when diving
- it can save your life or your buddy if get tangled in fishing line, kelp or seaweed
- makes easy to cut yourself off from the freediving buoy or line if there is an emergency
- you can remove old fishing lines, ghost nets from the ocean
- helps to free marine life trapped in nets or lines
- a useful tool if you need to search for something in the sand
- serves as an anchor to the sea bed and like this, can prevent you from drifting away in strong current
- works as an underwater signaling device, you can knock it on your weight, rocks or on a metal object (for example wreck) to give noise signal to your buddies
- can be used to tighten or loosen screws if there is no proper tool around
By spearfishermen, a knife is an essential part of the equipment, while recreational divers and freedivers rarely, in ideal situations never use it because no emergency situation happens to them.
But since fishing lines and ghost nets can be present anywhere, it is better to have one so if necessary, you can quickly react. Carrying a good cutting tool is crucial when freediving since you have limited time to resolve an entanglement, free yourself and resurface.
What type of knife to choose for diving?
Diving knives are available in various sizes with different blade types at all quality levels from budget to professional ones. It depends on your diving style which is the best for you.
Spearfishermen should choose one that fits their fishing habits, while technical divers need the highest quality models. For recreational divers and freedivers -who carry cutting tools mainly out of safety reasons- compact sharp-tip knives or line cutters work the best.
What makes a good diving knife?
- compact size, durable construction
- rust-free titanium or stainless-steel blade
- secure, easy-to-open holder
- ergonomic anti-slip handgrip
- easy mounting
Where do you wear the dive knife?
It should be worn on a place where it is easy-to-see, easily reachable with both hands and doesn’t restrict your movements. Most divers wear it on the belt, on the leg or on the arm. All the placings have advantages and disadvantages.
If you choose to attach it to the belt, in an emergency situation you might need to drop your weight belt, and like this, the knife will be also gone. Wearing the knife on the leg is not the safest solution according to many divers, since your legs are the most likely to get tangled. If this happens, a knife on the leg becomes useless. Should you decide to mount it to your forearm or bicep, you can reach it with one hand only.
To minimize the risk and maximize safety, the best is to mount your primary knife either on the calf, thigh or the belt and wear an extra line cutter or shears on the forearm or on the wrist.
The best dive knives
If you decided to add a knife to your freediving equipment reading the above mentioned practical and safety reasons, here are some of the best models you should consider to buy for freediving, recreational diving or hobby spearfishing.
This Riffe compact knife is a great all-rounder choice for freediving and spearfishing. It cuts through stainless steel cables and high-tech Kevlar fishing lines with ease. You’ ll never be tangled up in a situation you can’ t get out of if you carry this Riffe diving knife with you!
The stainless steel 420 blade resists corrosion ensuring a long lifetime. Thanks to its compact size, it can be comfortably worn on the leg or foreman using the adjustable rubber straps.
- heat-treated Teflon coated stainless steel blade
- compact size
- leg and forearm straps
- grey or orange color
The Promate Titanium is a full-size multifunctional diving knife. It has a total length of 9.45″ (24 cm) and 4.45″ (11.3 cm) blade length making it a great choice for diving, freediving and spearfishing.
The corrosion-resistant titanium straight blade features a partially serrated edge and a line cutter too. Adjustable straps allow easy attachment. The double-button push release sheath ensures maximum safety, while the rubber grip provides a secure hold.
The Promate Titanium knife is available in sharp or blunt tip versions that can serve as a screwdriver too.
- high quality for reasonable price
- rust-free titanium blade
- durable ABS plastic sheath
- sharp or blunt tip versions available
Compact, functional and ergonomic model that is recommended for any type of divers. Thanks to its dimensions, Cressi Predator is a perfect safety knife that fits the leg or arm without restricting the movements.
The high-quality Japanese 304 stainless steel blade has a straight edge on one side and a serrated section on the other. It features and extra black coating for extra durability. Rubberized non-slip handle and blade guard add extra safety, while the durable sheath and strong adjustable straps allow quick and secure attachment. A great small drop point tip knife!
- compact and lightweight construction
- 3.39 inch/8.6 cm Japanese stainless steel
- durable sheath with strap eyelets
- rubberized ergonomic handle
The BOffer diving knife is a cheap yet functional rugged cutting tool that is perfect for scuba diving, freediving, spearfishing and underwater hunting. 4-inch long, 0.14inch thick straight 420C stainless-steel blade with sawing edge on one side cuts through even the strongest lines. The paracord wrapped handle provides comfortable and secure holding.
For maximum functionality, the BOffer dive knife package includes an ABS plastic safety release button sheath, a nylon sheath for easy belt-mounting, as well as adjustable and elastic straps. A decent product for its price!
- 420C stainless steel 4-inch blade
- diving sheath with adjustable straps to wear on leg/arm
- snap closure sheath to wear on belt
- easy-to-use quick-release holder
Belt-mounted line cutter
If you don’t feel confident enough to carry a dive knife with you, a line cutter is a good replacement. This small and inexpensive safety accessory with sharp blades cuts webbings and lines with ease.
Although it is not that multifunctional as a knife, but helps to free yourself or your buddy in an emergency situation. It is also a good idea to have it as a secondary cutting tool placed so that you can get it even when you can’t reach your knife.
The line cutter is easily mountable on the weight belt or it can be worn on the wrist, arm or leg too using the wrist or harness pouches. The safety design ensures that it is almost impossible to cut yourself.
- great alternative cutting tool
- cut lines up to 12 mm thickness
- sharp blade, safety design
- with wrist, harness or neoprene flexi pouch for easy mounting
AG is a certified diver and freediver who started to explore the underwater world in 2005. He enjoys sharing his experience of the best freediving destinations and equipment tips as well.
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