Best knife for ocean or water use?

Jun 15, 1999
Assuming I'm going to be underwater, or near water and need to cut stuff quite a bit. What's the ideal knife for this job? Navy Seal 2000? Others? Would love some input here for a good water knife...
For use in and around salt water, you might consder the ceramic line of knives from Mad Dog.

Another option would be the Titanium knives from Mission Knife and Tool. I have the MPT from Mission. It's quite a well designed piece, but the cutting edge just won't get as sharp as a steel knife - it does have really well done serrations.

Rob Simonich makes knives from Talonite which is a nonrusting alloy. These knives might make a good choice too.

The other option is to buy a rough and tough piece of s*** and throw it away when it gets too rusty... which if it's made from normal 420 stainless might even be a while.


Mission Knives MPK? It ain't the easiest to sharpen, but it will never rust. Of course, it costs about as much as an entire wetsuit.

One knife that hasn't been mentioned here that I've seen is the standard Military USN Mk3. I've read that the SEALs have used that as their primary knife for years. The price is right, at least.

It's the bottom one.

Vampire Gerbil: similar to a domestic gerbil, except the odd accent and little black cape.

The ideal would be a Talonite dive blade from Kit Carson, Rob Simonich, or Trace Rinaldi.

Buck makes a "400 Series" steel version of Kit Carson's dive knife. Looks like a great knife, but it isn't cheap for non-specific blade steel (around $120).



PS - Image borrowed from Thanks Howard!

One thing to keep in mind -- everyone I know who does a lot of diving says that they lose knives. A lot. Even if they never lose one on dry land, things tend to get lost in a diving environment. So one of my important criteria for "best knife around ocean use" is this: WHEN I lose it, how badly will I cry? For me, anything under $100 I'll probably only sob a little, $100-$150 I'll break out in tears. You should consider carefully what those limits are for you!

Point taken Joe. I don't plan on doing any diving much, but being in the ocean and/or lake will be mostly, even if it be knee deep.
Navy Seal 2000 - are those weather tolerant? Heard they were ideal for harsh climates.
Steve - what's up with those "tipless" knives? Serve as a backup screwdriver?

Most people who work around water tend to do a lot of prying -- hence, the chisel-tip knives.

my choice would be 440c on a budget...talonite if cost is no object... if you lose them a lot maybe you better go with the buck....or maybe something even cheaper/ if you read the tactical knives may 99 review of the ceramic knives named above.. prying was a REAL weak point....ceramic breaks....those are the facts!

[This message has been edited by tom mayo (edited 21 September 1999).]
Ditto everything by Tom Mayo...affordable: 440c... money to burn: talonite... ceramics: fragile! (even the MDogs)

I haven't been diving in two yrs but expect to start again next summer, so have been thinking about a water-friendly knife. Also, have been thinking about what to purchase as my LAST general purpose knife (do I hear someone laughing?). Decided to kill two birds w/one stone, go the "bleed my wallet" route (Tom's "price is no object" option) and ordered a 4.5" drop pt Talonite from Rob Simonich (so who's laughing now?). Should arrive late winter/early spring...

Tuff: The SOGs are all 440A, I believe, yes? Not "ideal" (depending on what you mean by that) for edge-holding, but will stave off corrosion 'bout as well as any steel can, esp if you're just round fresh water...

Joe's pt should be well-heeded too: whether affordable or not, always use a LANYARD round water!! Convenient to have a cord lock on the lanyard, pretty much dummy-proof.
I spend a lot of time in, on or under the water. I live on Florida's Intracoastal Waterway and boat and dive in salt water.

Do not buy fancy knives to use around water!

For everyday marine carry you can't beat a Spyderco folder. I prefer a 50/50 Delica. Easy to carry in shorts or a bathing suit. On the water, when you want to cut a line, you want to cut it NOW. Nothing beats Spydie serrations.

Other alternatives are the Endura or Rescue with a sheepsfoot blade (no sharp point) or a Spydie Snap it. This model has a spring shackle that can attach to a D ring or belt loop.

Maintenance is easy. After use, I rinse the knife in fresh water. When I get a chance, I'll wipe it down with a Marine Tuff Cloth. Otherwise, I'll use Breakfree, WD 40, or Boshield or whatever's handy. Flitz will take of any small rust spots.

The 8A blade sharpens up easily on my Sharpmaker.

Beat of all, these models all sell for under $40. No big deal if you lose it.

YMMV, but this has worked for me for over 10 years.

Dan Harris
Though I don't get in as much diving as I would like, I do enough to second or third the inexpensive, little pain if you lose it, approach on this subject.

Actually, I have found several inexpensive knives to be great in the marine environment. IMHO, folders should be avoided for reasons of strength and reliability. All it takes on some folders in my experience is sand or other gunk in the liner to cause a locking failure. One handed or two handed opening is also not as graceful underwater as it is on land. Go fixed.

Frosts of Sweden make for excellent fishing knives. For just a little money you can get brightly colored handles, plastic sheaths, and afford to lose/break them by the dozens over the years with no tears shed.

In diving, depending on if prying is foreseen, I use either a Kabar warthog (prying) or a regular one (dubious shark defense and kelp hacker). Both are modified with the coated blade and the pommel airbrushed in a day-glo yellow marine epoxy I had made up so I can better see the knife in the long light wavelengths under water if I drop it. I have also made lanyards, attached through a hole drilled into the top of the guard, with a hangman's noose of reflective cord from the Campmor catalog. I then velcro the knife sheath (knives, sometimes they both go), to my calf. Ready to go to the kelp forests off of the Oregon coast and hang with the wildlife.

The coated 1095 blades can be made razor sharp, hold an edge better than most stainless and aren't as prone to rusting as people tend to think. The large fixed blade is also a usuable chopper in the kelp if absolutely necessary. Try that with a four-inch folder.

Remember you need oxygen and mositure in significant quantities to oxidize steel and form rust. Underwater, a carbon blade will degrade over time from dissolved oxygen in the water, but nowhere nearly as fast as you will. Oxidation attacks your blade far more rapidly in the air than in the water. The Titanic is still down there rusting away, all of the people are long since part of the environment, right? One could probably recover usuable steel from that 88 year old wreck today and make a knife out of some part of it. If your sheath has a drainhole and you can take but a minute a day to wipe down a coated carbon blade with a tuff cloth or something like that at the start and finish of the day, you've got yourself one pretty tough, yet eminently destroyable or "loseable" marine knife.

Save the hundreds of dollars spent on some "unrustable" or "unsharpenable" knife and buy a better outboard motor or wetsuit, regulator, fins, lights, cameras, etc. Why spend hundreds on a marine environment knife unless you use it everyday in conditions where you cannot maintain a "lesser" knife with minimal effort? Seems like a waste of hard-earned money to my bean counting eye.

If you are a SEAL, buy a SEAL knife or something high-end. If you are a recreational diver, use something you can afford to lose and take several copies on the boat. Losing a cheap, but tough as nails knife underwater and forever means never having to apologize to yourself for losing the expensive blade, having to save up for months on end, ask if your credit card has a loss protection feature, or having to cajole the wife for another couple of hundred dollars for a knife you already had to cajole her into letting you buy in the first place.

[This message has been edited by Oregon Duck (edited 22 September 1999).]
I've had good results with the Buck 400 series. As a backup, the BM titanium Emerson is also good, but these were for ocean kayaking and not diving.
Tom when you refer to ceramic breaking are you talking about MD's knives? These are not ceramics, they are ceramic-composites. Describing them as ceramics would be like calling steel iron. Ceramic composites are much stronger and tougher than ceramics. I don't have any specific info on MD's composite as he is not telling what exactly it is, but in general there is a big difference.


I assumed from your mention of the SOG 2000 that you are looking for a bigger knife, but if you are considering something in the 4" range, David Boye's Basic III is a great choice. It comes in 440C stainless (Boye Dendritic Steel - BDS) for about $60 and in Boye Dendritic Cobalt for about $150. These make great basic water knives if you wrap the handle in some paracord.

Whatever you decide, invest in some Marine Tuf-Cloth. It'll be be the best $10 (or whatever) that you spend this year...

Clay Fleischer
AKTI Member A000847

Specialization is for insects.
I know. I need me some tuff cloth, ogt to remember to pick some up.

Why can't Home Depot carry that stuff...