Dive knives when out with a DM

[Gone for diving]

Leatherman question: how well do they work around seawater? Do they rot over time or is the stainless steel good quality -- including the rivets?

I ask as they're undoubtedly great tools, but if you can't abuse them in the sea and not constantly rinsing them then other tools would be better.

(Have never owned one so genuinely interested)

I am quite sure it would stand up to saltwater,,,, but I hardly ever dive saltwater...
also I don't take it diving, it's not practical for use with thick gloves, as a mechanic and Jack of all trades,,, I carry it one me normally...

 

[RebelYell63]

For some guys it is a “look at me” thing, but for me….as a former NJ ocean diver, having a knife was a lifesaver——especially for those times when you get caught up in some fishing line. Not necessary, but definitely gives some comfort. I used to wear it down around my calves but that’s mainly because I had enough crap in the way. Not only that…god forbid I puncture my expensive BCD or drysuit…..

 

[FF / EMT]

For some guys it is a “look at me” thing, but for me….as a former NJ ocean diver, having a knife was a lifesaver——especially for those times when you get caught up in some fishing line. Not necessary, but definitely gives some comfort. I used to wear it down around my calves but that’s mainly because I had enough crap in the way. Not only that…god forbid I puncture my expensive BCD or drysuit…..

Around that calf is a terrible place for a cutting tool, it needs to be somewhere it can be reached by both hands if needed to cut yourself out, ideally at the waist strap or above, I always get a chuckle when I see someone that has it around their calf.

 

[tursiops]

I follow and agree. But credit where credit is due, these cave folks were at least partially responsible for:

Modern wing and backplate BC
Single piece harness
Long hose primary (40 or 60 inches for open water)
So called streamlined rigs (no consoles, dragging octos, BFKs on the leg) with everything in it's place
B&G spgs
Team diving
Deco acceptance
Can lights
Slinging cylinders
Side mount (dangle mount, lol )
Isolation manifolds
And then I suppose GUE, DIR and all of that.

And I think these early guys also helped push the envelope that eventually led to wide mainstream use of trimix/nitrox and CCRs and "Technical" recreational diving.

This trip to Florida, which is not really over yet , I saw and have seen more BFKs strapped to legs since the 70s. I guess I should pull out my Sea Hawk for my next dive, just in case a Great White needs to be attitude adjusted or a manatee needs harassment.

James

PDF

Technology Transfer in Diving:​

 

[Joris Vd]

My mother had a BFK for a long time. It was a black version of this old thing:

I dive with a trylobite cutter on my belt

and this tiny thing in my drysuit pocket just in case I might ever need an actual knife...

needless to say it has mainly been collecting seaweed in my pocket...

On dives where there's an actual big risk of line entanglement I wear a pair of emt-shears bungeed to my arm under my computer;

These rust like hell so honestly I wouldn't recommend them except for those few dives you'll ever do where there's a big risk of getting entangled ((for example a net cleanup / lake cleanup / anything cleanup related to rope basically)

The change of bigass knives to trylobites and small cutters reminds me a bit of Alpine Style climbing.

For a very long time climbing was done in a siege style manner with hundreds of pack bearers, many many checkpoints, base camp 1,2,3 etc and then on the final day an ascent would be made by the select few.

The exact analogy could be made to late 90's technical diving actually.
People wore so many things as a backup to the backup of the backup that they got very convoluted and it caused more potential issues than the risks it prevented or problems it solved.

No more 10 dive light setups , 4 computers on each arm, double winged bladders, double inlet and exhaust valve drysuits.
Now, we realise that it's better to mitigate risk by packing (as) light (as needed for the dive) and going in and out smoothly.

Back then people thought they might need it to cut line or screw something / crowbar something/unwedge something or heck in the 50-60's i'm pretty sure some people thought they might actually need it to defend themselves...

I feel like it's more a natural evolution of diving than an ego thing.

 

[Eric802]

Around that calf is a terrible place for a cutting tool, it needs to be somewhere it can be reached by both hands if needed to cut yourself out, ideally at the waist strap or above, I always get a chuckle when I see someone that has it around their calf.

You can’t reach your calf with both hands?

 

[FF / EMT]

You can’t reach your calf with both hands?

Not when I’m tangled I can’t.

 

[boriss]

I am not sure about that.

Well, it's a fact, here are a few examples:
The famous incident with David Shaw...
Fishing line: Dead diver's breathing gear found tangled in fishing line
Rope: Scuba diver drowns in Sattahip - Pattaya Mail
Cave line:

 

[SlugLife]

I find it interesting that some people have only had to use their knives/cutting devices once in thousands of dives. I'm new to diving and I've already had to use my Trilobite twice when tangled in fishing line on a wreck. Once while going through a tight restriction inside a wreck. That honestly scared the crap out of me. The line caught me and wouldn't let me continue forward. Was easy to cut it, but the timing sucked... scared me a bit.

I've used a BFK during rescue class to hold against current, but more importantly, to mark location when doing our search pattern.

Lastly, I've seen people get tangled in their own line, that had to be cut apart. Many people have died from entanglement in cave line, fishing line, rope, etc. IMO cutting devices are pretty important and I never judge people for what they bring with them. What's that saying? It's better to have it and not needed, rather than need it and not have it?

It heavily depends on where you dive, and some random chance. For example, in the vast majority of my dives, I don't become entangled in anything. However, for a dive last year, I visited a new location on the same lake, and had at least 10 fishing-line entanglements in a single dive. I could have handled it all without a cutting device, and none of it was particularly risky, but the cutting device made it a lot easier.

I also recently added some "powerhouse" shears to my kit as well for boat rope. Not that I absolutely "need" it, one of my line-cutters opens up with a serrated blade on one side and can cut rope. However, it does take a bit of effort (therefore time and air). The shears slice through every rope with ease, which means I'm more likely to cut up any rope I encounter into smaller pieces, rather than leave it as an entanglement hazard. It's also useful for retrieving nice boat-anchors, which may be tangled in a bunch of other anchor--ropes.

"Many" people, hmmm, not sure about that. I think it pretty rare.

Many vs rare. These are subjective terms to an extent. Probably the most interesting point is that it does happen. Scuba divers are found dead tangled in line, and those topics come up periodically over in accidents and incidents, or sometimes in Dive Talk videos.

Another factor worth considering is people not-dying, because they have cutting devices.

 

[Nemrod]

I am going to stay with what I said. Death of a SCUBA divers due to entanglement is not something that "many" would apply to. It is rare. In 54 years of active diving I have never drowned from being entangled while SCUBA diving nor do I know anyone who has or anyone who knows anyone who has.

The video is an example of an UW CF where unprepared divers undertake a dive beyond their knowledge, training, equipment, planning and capabilities. The entaglment in sucide clips was the immediate cause, the other things I listed are the real cause. And there is not a "legal" depth limit and sensationalized youtubes and Quroa and Faces book are not vetted.

The drowning of the lady diver in the lake who was sitting on a rock seems to be purely speculation and I could not or would not draw any conclusion from that accident description as to actual cuases.

If you wish to carry a BFK, have at it. I do carry a knife and a Trilobyte and often shears. New divers sometimes go through the BFK phase, they bought an underwater sword, it was expensive and cool looking so of course they want to use it. My Sea Hawk, Grisbe Knife and several others including the famous Buck 122 Nemo underwater Bowie Knife reside in my gear bin. Shoot, I use the Buck for hunting where even there it gets the eye, like, where the heck did you get that knife!!!!!!!! Now, that is a knife!

If anyone can provide a vetted statistic that shows that out of X number of dives that Y number of SCUBA divers drowned from entanglement and Y number was a significant percentage of X I will entertain it. And we can argue what significant might mean but I would wager, with only a guess based on life experience, the actual percentage would be way down in the fractions of well below 1% range. Coronary events are a much more prevalent immediate cause of SCUBA deaths. And a BFK is not going to help there.

N