Recommendation? Underwater knife

I am not a scuba diver (did it only once) but I have been spearfishing for 23 years (since I was 14). My needs are somewhat different than those of a scuba diver.

Therom said:
When I am diving I usually take my Salt 2 with me.
I don’t really see the point of a fixed blade where I am diving so this small folder work just good for me
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Folding knives are a big no-no for me. If you drop it while trying to open it, it is gone. And if you are trying to cut you free of a tangle, you are in deep trouble. I would say they are not ideal for a scuba diver either.

Velitrius said:
I prefer blunt tip, so I don't pop a hole in my BC or my suit or my epidermis. Something with a bright handle.
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You don't need to kill prey, so I would say that a blunt tip could be preferred. Bright handle is key as well!

It has been mentioned above the DiveRite knives (cutt off Victorinox steak knife in a plastic molded sheath attached to the jacket). That could work as a secondary blade, but I feel it is too short and flimsy for the main knife.

Velitrius said:
In all my years of diving, the only reason I ever pulled knife from sheath was to rinse, dry and silicone lube it after a dive.l
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I have gotten out of tangles with abandoned nets and monofilament a few times.

Mikel
 
Mikel_24 said:
Folding knives are a big no-no for me. If you drop it while trying to open it, it is gone. And if you are trying to cut you free of a tangle, you are in deep trouble. I would say they are not ideal for a scuba diver either.
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Fully agree

As I said it is just that I dive in really clear water and IMO the risk to get catch in a tangle doesn’t seems realistic.
Otherwise I share the same analysis as you and I would go for a fixed blade 100%
 
I did a search of the forum and came up blank, or my Google fu is not as good as I would hope. I carry every day but usually autos or folders, while on duty, or deployed or at home. I am on our department's specialized rescue team, and a national rescue team. I will be using the knife on my PFD, on my BCD, and on my belt almost every day. I am looking for a hard use knife, fixed blade and not super huge. I looked at the Medford BOA-B but am having a difficult time sourcing one to try in my hands.

I am not very happy with the Swift Water/Dive/Rescue knives out there and am looking for some recommendations from the forum here.

Thank you in advance and stay safe.

Tack
 
For spearfishing, I use a beauchat mumdial little dagger. One side is serrated .

These things just work and don't rust . I often don't remember to rinse them... And I never rinse or even dry them after freshwater dives . Same with most spearfishing knives .

Alberta Ed said:
A stainless Mora (Sandvik 12C27 or similar) should work well in/around salt water.
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I took a Mora recently on a few dives and more care is required after, but they can work. Best not the sheath them after you rinse and "dry" them .

MOST IMPORTANTLY... Make it a low-production, no longer than 5" blade (even 3 is fine) and wear it at 12:00 on your belt .

This way, you can reach it with either hand quickly .

Only '70''s Cousteau / Bond wannabes wear an 8" Rambo knife on their calf or forearm.
 
Over 40+ years of diving (8,000+ logged dives), my dive knife preferences changed, primarily due to hat was available.

My current dive knife/cutting tool recommendations are -
Knives - short blade (3" to 4" max), blunt tip, bright (yellow) handles
EMS Shears - yellow handles

When I got started diving back in 1975, the large 7" blade Bowie style knives were just about the only thing available. If a new knife came out, I tried it.

The last knives I carried up (2 years ago when I was medically forced to retire from diving) were the short, blunt tip, yellow handled McNett Saturna knives and EMS shears. I carried 2 of each - one of each on both sides. Together all 4 tools weigh less than one of the massive knives everyone carried back in the 70s and 80s.

Yellow handles for visibility in the event they are dropped and the water is both clear enough and shallow enough to allow for safe retrieval.

Short - for 99.9% of all cutting duties, short is better for easier control, less motion required for pulling/replacing the knife in its sheath.

Blunt tip - You don't want to accidentally punch a hole in your BC vest.

Shears - the most likely thing to get tangled up in when diving in any water, clear or murky, is fishing lines. That was what was told to us in 1975 and it is still valid to this day. One may never get hung up, but the more you dive the more likely you are to encounter fishing lines.

The shears are necessary because a lot of new fishing line has Kevlar in its construction. These extremely tough fishing lines require eithe a very sharp serrated edge or EMS shears.

Any why 2 of each - if you loose one, you still have one.

YMMV
 
Anmol said:
Hello people, I am a scuba diver and am looking to buy a new knife for use in the water. I want a knife which will last for a decent period of time . There is a knife which I like but am not sure about it's suitability in salt water. The material is 5Cr15 and it says stainless , inoxydable. Can you please tell me if this one will be good to use underwater ?
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For scuba diving you want a fixed blade and serrations. You don’t want to be trying to open a folding knife underwater when you need your knife NOW. Serrations cut materials that may be fibrous which are likely to be encountered at sea. (Rope, fishing nets, kelp, etc)

There are certain specialty blade materials like titanium, stellite, dendritic cobalt that won’t rust. There are also some extremely to very rust resistant stainless steels such as H1(completely stainly) or LC200N (very very rust resistant).
 
Spyderco Aqua Salt serrated is truly rust free and a widely used dive and fishing knife in the Florida keys. Comes with black or yellow handle.

 
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GatorFlash1 said:
Spyderco Aqua Salt serrated is truly rust free and a widely used dive and fishing in the Florida keys. Comes with black or yellow handle.

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The Aqua Salt is a great knife and I will eventually get one. I think there is even a more recent model dedicated to spearfishers. Same concept, different blade shape.

My only concern about this knife is that the stock is very thin. I know I know... a knife is for cutting... And I applly (or try to) this moto anytime and get the right tool for the job. BUT when you are underwater, you don't usually have a fully kitted toolbox to choose from. And end up doing things you shouldn't with the knife. I have bent (S shape) a diving knife while killing a hard skulled fish (I could have gotten the brains from inside/under the gills but that's another story). Sometimes you pry with it... I fear that the Spydercos my just snap in half.

But agian, I will be getting one. Yello handle, satin blade. Just in case I drop it.

Mikel
 
Anmol said:
Hello people, I am a scuba diver and am looking to buy a new knife for use in the water. I want a knife which will last for a decent period of time. Can you please tell me if this one will be good to use underwater ?
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As you want a knife thatll last, I suggest you look at MISSION titanium knives (the one you mentioned in the OP will need maintenance and will eventually still show rust). I have several MISSION knives and am very happy with them. I use the MPS Ti for hunting, camp use etc and the MPU for kayaking, hunting etc. When kayaking, the MPU needs no maintenance and only gets rinsed because I rinse my vest with the knife in it after each kayaking trip. A MISSION Ti knife will last you forever. The MPU comes in different variations; blunt, pointy etc etc.
NB Dont bet your like on a folder when diving. You want a fixed blade.

Anmol said:
My budget maxes out at around 150$.
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Personally, I dont think you can put a price on your life. How ever, you mentioned a budget of $150.
In that case, I suggest a Spyderco in either LC200N or H1. You can get a knife within your budget from new or used.

https://www.knifecenter.com/item/SP...plain-blade-black-g10-handles-boltaron-sheath

https://www.knifecenter.com/item/SP...ack-serrated-blade-frn-handles-polymer-sheath

https://www.knifecenter.com/item/SP...-black-plain-blade-frn-handles-polymer-sheath

https://www.knifecenter.com/item/SP...rated-blade-yellow-frn-handles-polymer-sheath

You really cant go wrong with either of the knives mentioned above.


Monofletch said:
I know U.S. Gladius makes an all titanium fixed blade for salt water. I doubt it will hold much of an edge, but you don’t have to worry about rust! :D

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Tack425 said:
I did a search of the forum and came up blank, or my Google fu is not as good as I would hope. I carry every day but usually autos or folders, while on duty, or deployed or at home. I am on our department's specialized rescue team, and a national rescue team. I will be using the knife on my PFD, on my BCD, and on my belt almost every day. I am looking for a hard use knife, fixed blade and not super huge. I looked at the Medford BOA-B but am having a difficult time sourcing one to try in my hands.

I am not very happy with the Swift Water/Dive/Rescue knives out there and am looking for some recommendations from the forum here.

Thank you in advance and stay safe.

Tack
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Thx for those suggestions, I needed a good laugh:D
 
Mike 24 -

The Spyderco Diving Aqua Salt has 1/8" blade thickness which is decent for a fixed blade. My concern when diving is getting snagged on or by something (a trolled ballyhoo, etc. from a boat ignoring the dive flag is my biggest fear) so I carry an Aqua Salt serrated dive knife to cut me loose quickly from line, wire, etc.. That concerns me much more than the ocean critters I come across.

I'm sure Spyderco spoke with many very experienced divers to get the best design for their needs before starting the manufacturing process. They are pretty good at doing their homework, IMHO.


Some dive knives come with a pry bar tip, but that eliminates the stabbing aspect of the knife. You can buy just a small pry bar at any hardware store that would probably work if you don't mind lugging around two tools plus a spear gun.

 
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dirc said:
Here is a larger titanium dive knife, it will never rust and gets bonus points for being pry bar strong if you ever need one underwater
On sale for under $100 right now
https://www.knifecenter.com/item/UK...-Yellow-5-inch-Drop-Point-Titanium-Dive-Knife
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I'd avoid the cheap "titanium dive knife" things if I were you. Be way better off with one of those serrated spydercos.
 
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