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Welcome to Dive Gear Reviews, a comprehensive guide to scuba diving equipment. Scuba diving is an expensive pursuit, so looking up reviews for a particular article of equipment is a wise precaution before investing any hard-earned money in it. However, consumer reviews may or may not be written by an experienced diver, and magazine reviews could be suspect due to the advertising ties of the publication in question. Dive Gear Reviews provides cross-referenced reviews assembled by an expert, making it possible to see at a glance what multiple sources said about a particular piece of scuba equipment. If one magazine loved a scuba regulator or a dive computer, but the consumers hated it, that information will be found here.
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December

Dive Knife Guide

Written by Dive Gear Reviews Editor. Comments Off on Dive Knife Guide Posted in: Dive Knives, Scuba Product Guides

Dive knives have grown from being simple stainless steel tools into fairly complex tools made from a variety of materials. This guide to dive knives will help you navigate the many features available on modern dive knives, and thereby help you choose the knife most appropriate to your needs.

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This older version of the Scubapro White Tip comes with both serrated and standard edges, as well as a line cutter.

Construction
Most dive knives are made of stainless steel, and the most common type of stainless steel are rust-resistant rather than rustproof. Most stainless steel objects, including many dive knives, are made from a 300-series stainless steel. Steel from this type balance cost, flexibility, tensile strength and corrosion resistance. As a rule, a knife made from 300-series stainless steel will remain free of rust if it is thoroughly rinsed with freshwater after diving and allowed to dry and if the metal is periodically oiled. Whenever a diver does a basic maintenance review of his gear or puts his gear into storage, the typical dive knife should receive an oiling to improve its corrosion resistance.

Other dive knives use stronger stainless steel, but this is not necessarily more rust resistant. The Riffe Terminator is made from 420 stainless steel, which is harder than normal stainless steel, but no more resistant to rust.

Spyderco uses H-1 stainless steel in the construction of some of its knives, like the Atlantic Salt. This steel replaces carbon in the alloy matrix with nitrogen, greatly increasing its corrosion resistance. Spyderco maintains that H-1 stainless steel is truly rustproof, and without losing any strength in the bargain. Thus far, no Spyderco knife owners have complained that their H-1 steel blade started developing rusty spots or snapped in half under pressure, so it seems H-1 steel is the real deal.

Of course, for maximum strength and corrosion resistance, titanium steel is the standard. Titanium is used in knives like the XS Scuba Beta or Akona AK950, and is usually somewhat more expensive than the equivalent knife in stainless steel. However, it is hard to imagine a titanium steel knife rusting or breaking under even the most extreme conditions.

Blade Features
Dive knives come with either standard edges, serrated edges, or both. It is not uncommon for dive knives to have a single blade with both standard and serrated edges, or to have a double-bladed knife with a standard edge on one side and a serrated edge on the other.

Serrated edges are a bit like a saw, and because the point of cutting contact is reduced, serrated blades are more efficient and easier to cut with. However, the cuts involved are less precise, and serrated blades are more labor intensive to sharpen. The choice of standard edge vs. serrated edge is entirely about what you intend to do with the knife and how often you intend to sharpen it. The typical recreational diver, for whom a knife is a rarely used safety tool, could get by just as well with any type of edge or combination therein.

Another common feature on dive knife blades is a line cutting notch. This is an indented, sharpened loop with the specific purpose of making cutting fishing lines easier. Since fishing lines are one of the major reasons why most divers carry a knife in the first place, it’s a good idea to own a knife with a line cutter.

Knife Tips
All dive knives have one of three tips: standard/pointed, tanto and blunt. The standard/pointed tip is, as the name implies, the sharp, stabbing point typical of most hunting and combat knives.

The blunt tip is flat and unsharpened, making it the exact opposite of the pointed tip. While a blunt-tipped knife loses its utility as a stabbing weapon, it increases its utility as a tool and its safety margin. A diver can’t accidentally stab himself while putting the knife away with a blunt tip, and the wide, flat top makes the knife perfect for doubling as a pry bar.

Tanto tips are like the ends of samurai swords, like the katana, and are the most flexible tip type. A tanto tip can be used for prying without much fear of breaking the tip off, and it retains an off-center point for stabbing.

Size
The size a dive knife needs to be is directly proportional to the knife’s intended task. Most divers, who carry a knife only as a hedge against an emergency, need only a small knife with a three- or four-inch blade. Even cave and wreck divers, who often carry more than one blade, usually pack multiple small knives and shears, and not a single big knife and then small back-ups. In this respect, dive knives are not at all like dive lights. Substantially bigger knives, like the Cressi Orca and Aqua Lung Master, are for divers who need serious tools for serious work.

The Sheath Lock
Perhaps the single most overlooked feature of any dive knife isn’t part of the knife at all, but part of its sheath. Any dive knife that isn’t properly secured is guaranteed to be lost sooner or later. If the lock of a prospective dive knife looks flimsy in any way, don’t buy it.

The Pommel
Most mid-sized and large dive knives come with a heavy metal stud or cap on the bottom, which is meant to double as a hammer. If there is one drawback to small dive knives or folding dive knives, it is that they lack this feature. Although most recreational divers will never need a hammer, a plastic butt is no substitute for hard metal when you need to smash something.