Regardless of which type of scuba diving you’re interested in from wreck diving and cave exploration to simply taking nice tropical fish pictures a dive knife is recommended as a helpful and vauluable accessory. A lot of dangerous situation can arrive under water such as getting entangled in ghost nets and a dive knife will help you escpae many such dangers. When taking tropical fish pictures you may focus on the task at hand and miss a ghost net or other danger while pursuing a big grouper to get that price winning shot. In such a situation a good dive knife will help you free yourself from the net before things get critical.
You should consider the following things before buying a dive knife
- Make sure that you get a scuba knife that is right for you and your diving style.
- Learn how to use it in a manner that is safe for you as well as for your dive buddies. A sharp knife in the hands of an insufficiently prepared diver can cause more damage than what it prevents; especially in a panicky situation.
In this blog post we will take a closer look at the first point choosing a dive knife.
What size should the knife be
There are three main sizes of dive knives, big knives, mini knives and standard sized knives. The standard size is 4-6 inches (10-15cm) and a standard size knive can be comfortable mounted on your arm or leg. An import aspect to consider is making sure that the handle is big enough to fit well in your hand. A mini knife will have a 2-3 inch or 5-7.5 cm blade and can for instance be worn clamped onto a hose due to its petite size. They can however be hard to use wearing gloves due to their small size. It is therefore extra important to try the handle on a mini knife before buying it. Any knife with a blade that is longer than 6 inches (15cm) is ti be considered big and can though to handle with any degree of precision under water. You should only get a big knife if you do something underwater that really requires a big knife, otherwise a small knife is to be preferred.
What material should the knife be made from
Most dive knifes are made from titanium or stainless steel. Titanium knives tend to be the most expensive choice, but are on the other hand extremely resilient to rust and other types of corrosion and a good titanium knife will stay sharp for numerous dives. A stainless steel knife will on the other hand be more susceptible to rust and corrosion, but you can counteract this by rinsing it off in freshwater after each dive and leave it to dry completely before putting it back in its sheath. Coating it with a layer or oil or silicone is also recommended.
Serrated edge or not?
Depends on what you want to cut, a straight edge is better for cutting artificial material like nylon while a serrated edge is better for cutting natural fibers. Serrated knives with serrations along the entire blade is better as that make is easier to use it as a saw. Today, you can also find multi-purpose dive knives where both types of edging is present on the same knife.
Sharp tip or not?
A blunt tip is better for the avarage joe diver while a sharp tip can better for divers planning to is it while spear fishing. A sharp tip will easily break if you try to use your knife to hack, chisel, pry, dig or similar. A blunt tip is a lot less likely to end up damaging your scuba gear than a sharp tipped one.
Do I need a line cutting notch?
Yes, I would recommend getting a dive knife with a line cutting notch since it can come in handy if you ever need to cut a small line.