Spyderco Salt Series folding knives are the only type of knife I carry while paddling. While available in a variety of blade designs and lengths, they all share some common characteristics. Salt Series knives have handles made of FRN, fiberglass-reinforced nylon, a tough, lightweight material impervious to temperature and to most solvents. These knives are pinned construction, meaning that you can't take them apart; this isn't a big deal, and has the advantage that your knife won't ever fall apart because a small screw came loose and fell out while going downriver (don't laugh – it happens).
These knives have locking blades – the lock is on the spine of the blade and has a "David Boye dent" milled into it, making accidental release of the blade very unlikely, even under heavy use. The single most noteworthy characteristic of these knives is the blade steel. For years I have preferred carbon-steel blades for their toughness, but if you carry carbon steel around water you'll often spend more time cleaning and oiling the blade than using it.
Spyderco Salt Series knives use relatively new "super-steel" in their blades, proprietary steel from Japan referred to as H-1. My understanding is that H-1 steel uses nitrogen instead of carbon to precipitate hardness in the steel matrix: the upshot of this is that since the carbon is the element in the steel that facilitates rusting, H-1 steel is not just rust-resistant, but actually rust-proof. Certainly other manufacturers have been working on "stainless" steels for years, but most of these steels are so soft they won't hold an edge, and you consequently find yourself sharpening them constantly. H-1 steel is different – it has the wear characteristics of the better carbon steels without the problems with rusting. In fact, H-1 steel actually gets *harder* every time you sharpen it (no kidding), meaning that your sharpenings get less and less frequent the longer you have the knife.
Spyderco produces several models worth mentioning to the paddler, but my personal favorite is the Tasman Salt. The Tasman is a knife with a hawkbilled blade a little under three inches long. Overall, it is four inches long when closed and not quite seven when open. This knife only weighs two ounces – that's TWO OUNCES. You don’t even know it’s clipped to your PFD until you need it. It has a lanyard hole for tethering to your PFD and a rust-proof, titanium pocket clip. The blade has the trademark Spyderhole in it to enable you to open it with one hand. The Tasman Salt is available with either plain edge or fully serrated Spyderedge blades, and either black or bright yellow handles (interestingly, when asked why yellow handles instead of, for instance, safety orange, Spyderco indicated that the yellow actually proved to appear brighter to the human eye underwater than the orange did).
A lot of people think that hawkbilled blades look kinda' dangerous and nasty, but they're actually safer than you would think. First, it is unlikely you'll accidentally stab yourself with one – the curve makes it really difficult to shove in the point. Second, hawkbilled blades tend to pull whatever you're cutting into the inside curve of the blade, making them excellent for cutting rope and netting on a boat without chasing and just pushing them around the way a straight blade tends to do. They're also fairly safe if dropped, unlike a straighter blade that would easily stick into your foot, lap, or the bottom of your boat.
To answer the next question, yes, these knives are actually 100% rust-proof. I personally own one of the very first Tasman Salt knives made (circa 2005), and it has been with me in the Atlantic Ocean on vacation numerous times, in the local lake incessantly in the summertime, and is now making its way down every river in WV that I can get my kayak into. My maintenance on the knife is limited to sharpening it once in a while, occasionally placing a drop or two of oil on the pivot pin to keep the blade movement smooth, and making sure that I don’t have a bunch of pocket lint down inside of the handle that could compromise the integrity of the lock. That’s it – no oiling of the blade at all, no cleaning off rust. It doesn't matter if I cut acidic fruits or vegetables, meat, branches or rope – it handles everything I throw at it and still looks new.
Do I own other brands and models or knives? Sure. However, when I am near, on, or in the water I carry a Spyderco Salt. They're not exactly cheap, as street prices average a little over $50, and if you’re the type that loses knives you’ll probably want something cheaper (I tend not to lose knives). They're really the best knife for those of us in watersports that I have found yet.
