Relentless Knives Perpetual Edge Fillet Knife


Filleting Fish

I’ve been cutting up fish one way or another for most of my life, the fishing bug bit me as far back as I can remember. And like many parts of the outdoor lifestyle, it took some time for me to figure out the proper way to do things.

Catching and cutting up fish has since become second nature, and a great filleting knife has long been my companion. But today I want to show you something new: Relentless Knives Perpetual Edge™ Fillet Knife.

The Perpetual Edge

The technology behind the Relentless knives edge is borrowed from nature, the idea taken from the sharp bite of the beaver.

The edge of the Perpetual Edge blade has two sides, like most blades. The one side however uses a carbide/crushed diamond surface, which makes that side of the knife particularly hard. The rest of the blade is made from titanium, which is much softer.

Much like the self sharpening teeth of the beaver, the softer side of the blade wears before the carbide side, which causes a natural wear pattern that thins the angle of the cutting edge. Keeping it sharper than it would be if both sides of the cutting edge wore at the same rate.

Sucker for sharp edges

You could call me a sucker for sharp knives. Just ask my wife how up-tight I get when my good knife edges get too close to something hard. Often I keep a knife sharpener in my pocket and in my office. The soothing therapy of smoothing and polishing knives to a mirror shine is a favorite pastime.

I am constantly checking and correcting the cutting edge of my pocket knives, hunting knives, and fillet knife. Because I can’t stand the idea of a knife not being razor sharp, there are few things more satisfying than a clean cut.

Field Testing Relentless Knives Perpetual Edge

Seeing how the sharpness of the perpetual edge stood up to some modest filleting work was my next task. Rainbow Trout is a far cry from saltwater fish, but unfortunately thats what I have at the moment. Having had this knife to fillet the dozens of Red Drum and Sheepsheads I caught on my last trip to the gulf would have been nice. Filleting and preparing all that fish for a large crew would have been easy work with this knife.

The model shown here today is the seven-inch curved blade model. They also make a six-inch, and nine-inch curved blade models. There are also two straight blade models in lengths of eight and ten-inches.

Check out the full line of Relentless Knives

Their seven-inch model should easily handle most of the fish I typically fillet. Which besides trout might include lots of striped bass, sunfish, Walleye, Channel cats. As well as the occasional salt water fish like those mentioned above, or the occasional mackerel if I’m lucky.

But today we are just filleting freshwater Rainbows, as that’s what I have for the frying pan. I must say that before I even got to feeling the edge of this knife. Its handle had already caught me. The texturing of the grip area is so sticky and course to your hand, I don’t think any amount of fish slime could cause it to slip.

To start I sliced through the skin towards the bones behind the head. The narrow tip of the knife made for some very tactical maneuvering and slicing to avoid wasting the tender meat. I could easily finesse the sharp tip around in the tight spaces behind the collars. And as you might imagine, the blade zipped through the bones.

Its sharp edge perfectly sliced the flesh away from the bones, taking off whatever it touched. And cutting the meat away from the skin was just as smooth.

After cutting up a half a dozen fish, I was quite pleased with the performance. But c’mon, a bunch of soft trout is hardly enough to dull a good knife right? Maybe the only choice I have to truly test this edge is to go catch a dozen Yellow Tail Mud Tarpon out of the marsh near my house, and run them through.

The thick scaly carp that live there are full of tough bones, and scales as thick as fingernails sometimes. That would really be a good test of how long this edge stays sharp. And if it truly does sharpen as it cuts like its manufacturer suggests.

I’ll have to update you all on the performance thereafter. As this knife ages I will update this article with some additional developments.

Pros & Cons

The Relentless Knives Perpetual Edge Fillet Knife is certainly sharp, as are most blades when they come from the factory, I polished it up a little bit to enhance its slice.  Designers of the blade left the carbide side of the edge flat, so there is no ground angle to the edge. The ground angle is only on the opposing side of the blade, where you do any sharpening if needed.

We found that the knife doesn’t cut straight because of this uneven profile on the cutting edge. It sort of slices to one side like you might imagine. This of course is not a big deal, and something you will simply adapt to as you continue cutting through fish after fish.

The sheath of the knife if you care about using it, is strong and will protect the edge of your knife. Though I wish it had a slightly better way of securing it to the handle.

Final Thoughts

As you might imagine I can’t wait to get my hands on more fish, and see how this edge holds up. I often use my fillet knives for boning out deer and elk as well. So it might show up on my butcher table as well this fall.

It’s not uncommon for me to cut through a pile of a couple dozen Stripers, and turn them into a clean pile of scale-free fillets that eventually turn into fresh made fish tacos. Without a doubt I am sure the sharp edge of this Relentless Knife will make short work of them when the time comes.


Like fishing, check this one out.

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