Oh, how times have changed! Increasing knife-crime on our streets has placed this humble but useful tool at the top of the modern list of items not to have in our possession.
Air travel with a knife is rightly impossible, unless it’s tucked away in hold baggage, but in any case most overseas resorts scowl at their use, or outright ban them on their dives.
In my humble opinion, a dive-knife used responsibly is an essential safety tool.
Both rod-and-line sport-fishing and ghost-net-fishing are leaving our dive-sites festooned with virtually invisible discarded monofilament or braided lines, and entanglement is a real possibility.
Without an effective means of cutting these lines or netting, they can be life-threatening for divers and marine animals.
In a first for me, I took TUSA’s latest mini cutting tool on test to see if its compact size would measure up to the mammoth task of keeping me safe.
The FK-14 Titanium Mini-Knife has a 70mm 6-4TI drop-point titanium blade. The lightweight corrosion-proof alloy used is durable and well-suited to the marine environment.
The short blade has a ground serrated edge on the back and a finely honed edge at the front, providing two cutting options.
The handle is moulded from ABS polymers, with a hard rubberised insert to aid grip, and is ergonomically curved to better fit the hand.
The FK-14 is supplied in an ABS sheath with a simple locking/release mechanism to keep the knife secured until needed.
A sprung stainless-steel belt-clip is fitted to the back of the sheath, with the option of replacing this with an ABS mounting-plate for high- or medium-pressure hoses; there is also an eyelet at the sheath’s tip for lanyard or piston-clip attachment.
The knife and sheath combined weigh 60g and measure 17cm in length. There are two colour options: metallic dark red or metallic silver.
I went into shock when my fishing-tackle sales friend produced a spool of 80lb breaking-strain “Spider Wire” braided line for me to use on this test.
“This is the ultimate evil for unsuspecting fish and divers,” I thought, as I tried to break the super-fine line with my bare hands.
My panicked chum quickly stopped me before I severed all my fingers. The limp green line is like cheese-wire, but cheese-wire you could use to tow a London bus.
The worry is that it’s becoming very popular in the sport-fishing world, and when anglers get hooked up on wreckage or a reef, pulling for a break is nigh on impossible.
They’re left to decide whether to cut the braid at the rod-end, leaving up to 100m of this almost invisible, loathsome product waiting to snare an unsuspecting diver in its potentially lethal trap.
The more widely used monofilament nylon fishing-line is much thicker and stiffer than the corresponding breaking strain of braided lines, but is just as malevolent for divers. It is also used to make commercial fishing-nets, and being almost invisible under water has been aptly named ghost-netting.
Getting entangled in any of these products is a seriously dangerous prospect, especially if you have no cutting tools to hand.
I put together a collection of sample lines that divers might encounter while going about their underwater business.
I’ve mentioned braid and mono fishing-lines but there are also traditional lines made from Nylon, polypropylene and polyester, or natural fibres such as sisal and hemp that are all twisted and braided to create ropes.
I’ve also included some low-diameter stainless-steel cable and hi-tec climbing line.
This was by no means a scientific set of tests. I simply sliced or sawed my way through all the sample products, taking note of how easy or difficult it was and how long it took using both the honed blade and the serrated back spine.
I wore a pair of 5mm neoprene gloves to find out how easy the TUSA Mini-Knife was to use wearing coldwater garb, then repeated the same operations with bare hands.
I also placed the knife and sheath in various positions on either my BC or weight-belt, to see if this affected access and deployment.
The honed titanium blade made short work of all the lower-diameter lines, slicing through them instantly with very little effort, and what pleased me the most was the ease with which it cut through the braided Spider Wire.
This, incidentally, proved very difficult to cut with scissors and, to my dismay when using my much-loved trauma shears, the fine, limp line simply folded between the cutting blades and remained intact.
The thicker lines needed a sawing action, and took between 5 and 10 seconds to cut.
The serrated back spine made short work of the mono and braid, but the serrations caught in the fibres of the thicker lines and ropes and slowed down the cutting process, with the climbing line taking 20 seconds to sever.
The one thing with which this cutting tool couldn’t cope was the 4mm stainless-steel cable, and I’m sure I took the fine edge off the blade while attempting to saw it apart.
The most accessible position (for me) was with the FK-14 mounted directly to the medium-pressure hose supplying my BC inflator. I’m right-handed, and with the knife-handle pointing downwards I found it easy to deploy.
The safety locking clip needs to be pushed forward to release the knife, so this is a two-handed operation – easily done on the BC hose but trickier when it was mounted to the side of my waist-belt.
The handle felt tiny in my palm with gloved hands, and I struggled with dexterity when attempting to cut the sample lines. I even dropped the knife a few times as I pulled it from its sheath, which is obviously not a problem in the lab but could be costly in a real-world underwater environment.
I’m sure this Mini-Knife’s small stature would have been the subject of much micky-taking and ribbing in my early diving days, with my buddies telling me “that’s not a knife, this is a Knife!” as they pulled their rusted, blunt 15in Bowie hunting blade from the side of their calf.
The truth is, this unobtrusive, low-maintenance corrosion-proof tool has proved that it can “cut the mustard” (pun intended) when the chips are down, and sliced its way through everything I threw at it, except for the tough call of the steel cable.
It’s also light enough for travelling, should some dive-operator actually allow it to be worn under water on overseas dive trips.
Entanglement is rare but it does happen, and if it does, this sharp little titanium blade could prove to be a lifesaver.
BLADE: Drop point 70mm 6-4TI titanium alloy
HANDLE: 90mm ABS
SHEATH: ABS with locking mechanism
MOUNTING: Belt-clip, hose-mount with FK-10HA adaptor (included)
COLOURS: Metallic dark red or metallic silver
DIVER guide: 9/10