Knives

A knife is a very useful spear fishing tool which serves two main functions. One, the knife will be used to dispatch a catch as quickly and humanely as possible. Two, a knife will be used to free a diver from entanglements such as netting, monofilament lines, ropes, etc. When choosing a knife look for a sharp pointed, dagger-like, blade with a serrated edge and/or a line cutter on one side. A smaller blade of approximately 4” (10cm) is preferable over the larger and bulkier options out there. The smoother and more streamlined a knife is, the less drag it adds to the diver. Most knives come with a flat nylon sheath and rubber straps so that they can be affixed to the diver’s leg or forearm. They can also be threaded onto a weight belt. The most important factor in knife placement is that it can be easily accessed by either hand.

Stainless Steel SCUBA knife (click picture for details) Most dive knives have blades fabricated from stainless steel for reduced corrosion. It is important to note that “stainless” does not mean “stain proof”. Even stainless steel blades will have surface corrosion if they are not properly rinsed with fresh water after every dive. There are various grades of stainless steel used in manufacturing which will be indicated by a number on the blade such as “440”. The general rule of thumb with stainless steel grades is the higher the number the more corrosion resistant, the lower the number the stronger the blade. Other materials are also being used to manufacture blades; most notably Titanium. Titanium blades are nearly corrosion proof and do not require any maintenance. They are usually close to double the price of a stainless steel bladed knife, but they will last a very long time. Titanium is however much more brittle than stainless steel and will not flex much. So Titanium blades do not bend as much as steel blades and will break if bent too far.

Titanium spearfishing knife (click picture for details)
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