Whatever Happened to Dive Knives? Our Recommendations

Back in the day, traditional surface-supplied hard-hat divers wore a massive Siebe Gorman brass-handled knife strapped across their chests in case they needed to saw through their heavy hemp lifeline. That's where the diver's knife first entered diving mythology.

Once scuba became popular, the first thing a would-be diver bought was a dive knife capable of slaughtering a grizzly bear. Having such a weapon strapped to your leg may have been legitimate for a scuba diver when it would have been classed as an offensive weapon for anyone else. But it signaled you were a macho dude and knew what you were doing in the underwater world. Even if there were never any chance of meeting and dispatching a grizzly down there.

Of course, such sabers were useless for dealing with the hazard most frequently encountered by divers: monofilament line. Good for cutting through thick hemp, maybe, but useless for slicing ghost fishing nets and detritus abandoned by anglers - even if an entangled diver could actually reach his calf to unsnap the case and retrieve his blade.

Eventually, the frustrating experience of unfortunate divers entangled in almost invisible monofilament was translated into small knives with line cutters built-in or (better still) trauma shears, strapped high up at the shoulder straps of the BC.

Come September 11, the traveling diver discovered that packing something that looked like a bayonet, even in checked baggage, could lead to all sorts of irritating and unnecessary questions at the boarding gate of an airport. Even more problematic, when you arrive in some countries and authorities discover a blade longer than four inches stashed in your luggage, you'll be having a conversation with law enforcement officers. So, keep that big knife at home and reserve it for your weekend barbecue.

A dive knife is not meant to be a weapon. It's emergency kit. What you want is a modern dive knife, small, with a line cutter for emergencies, a serrated blade for cutting through rope, and a sharp, smooth blade for making a sandwich at lunchtime.

Some suggestions: Stainless steel comes in various grades, but the more rustproof it is, the less sharp you can hone the blade. So instead of ending up with a knife that turns into a pile of rust in your dive bag, invest in a more expensive titanium knife such as the Scubapro Mako Titanium Knife ($155).

Atomic Aquatics produce quality products at a premium price, and the Atomic Ti6 Titanium Dive Knife at $175 list is no exception. Choose one with a useful blunt point that can be used as a screwdriver rather than a pointy ended one that's only good for hurting things.

As an alternative, consider Leatherman Raptor Trauma Shears, about $100, which are made of 420HC stainless and have lots of features besides scissors. You'll need to rinse and grease them between dives to keep them up to par.

For a similar price, you can get Maniago Pacific Junior Shears, which look more substantial in hardened stainless steel with grippy handles.

Zeagle Diver Tool Kit with EMT Scissors & Knife hedges bets over whether scissors or a knife are the best for a specific job. They come in a holster that can be attached high up on the BC ($80).

A cheaper alternative is Dive Rite's Trauma Shears in marine grade stainless steel at around $40, but the manufacturer is quick to insist, "Shears and sheath must be rinsed with fresh water and allowed to air dry after use to prevent corrosion to the blades. Corrosion and rusting are not covered under warranty."

Better than nothing when you're in dire need to release yourself from some line or net: Blue Reef Shears Cutter, which comes with a holster and can be picked up for less than $20.

- John Bantin