Relentless Perpetual Edge Knives

Relentless Perpetual Edge Knives are exactly the kind of applied technology I enjoy. They are knives that, by virtue of their design, never get dull. Using them actually sharpens them. Which is pretty much counter to most edged-tool logic. But that’s because the folks at Relentless combined modern innovation with a design found in nature. And the result is impressively simple.

Relentless™Perpetual Edge™Fillet Knives – inspired by nature

Conventional logic dictates that the best way to keep a blade sharp is to start with really hard steel. Which is all well and good, but it has some downsides. One, the hardest steels are usually somewhat brittle, resulting in chipped blades. Two, today’s hardest steels also require a lot more effort to sharpen. Everything is a trade-off when it comes to metallurgy. Enter “Nature’s chainsaw”, AKA the beaver. Beavers cut through trees using nothing but their teeth. Turns out those teeth are hard as nails on the front and softer on the backside. As they gnaw away on trees, the back of their teeth wears down faster than the front. This results in a nice sharp edge that stays sharp. Good for the beaver, bad for trees. Also inspirational.

Relentless Knives took this as a design cue. Their blades are a very hard carbide and crushed diamond “Power Strip” fused to a softer titanium base. By itself, this makes for a great cutting edge. Since the titanium is softer than the carbide and diamond side, it slowly wears down with use. As it wears, it continually exposes that Power Strip. And the result is a knife that never needs sharpening. Keep in mind that titanium is still pretty hard. So when I mention wear, it’s a very slow process. Even with daily professional use, it’s going to take a long time to wear down this blade.

Perpetual Edge™ Technology

There’s nothing else on the market quite like this technology. I’ve got a knife with a blade that’s comprised of high carbon steel laminated to 18/8 stainless. But it still requires sharpening. And it’s neither thin nor particularly light. Relentless Knives utilize 100% aerospace-grade titanium in their blades. Since titanium is both light and strong, the knives are lighter than expected, while being exceptionally strong too. And they will never rust, corrode, or degrade, even when exposed to harsh saltwater environments. I wish I could say the same for some of my other knives.

As you might imagine, the micro-serrated carbide/diamond cutting edge on a Relentless™Knife allows it to easily cut through soft fish with ease. Because fish are generally soft, they require a thin and sharp blade that has a bit of flex, but doesn’t crush the meat. Think filleting, not cleaving. To make this even more effective, one side of the blade is treated with SlickCut. This boron nitride compound reduces friction while enhancing lubricity. It’s not too different from nickel ammo cases, or nickel boron bolt carrier groups. The metal gets a super slick coating that lets it glide through whatever is being cut.

Getting a handle on Relentless™Perpetual Edge™Fillet Knives

With a blade this sharp, you’ll want a firm grip. So the knives employ a True Grit handle, which is made from glass-reinforced ABS. Taking it a step further, it’s covered with some gritty material for even more control. That material is the same stuff used around swimming pools to minimize slipping and maximize barefoot traction when wet. So you can trust it with your wet hands. It’s ideal for knife handles and well-utilized here. While they were at it, they also used a faceted surface texture, which scatters light. This prevents that black handle from getting hot in the sun.

Five Relentless Knife models:

Straight – This is the knife preferred for flatter fish like halibut and salmon, for which it has to maneuver around the spine during cutting. MSRP $239.99

10" Straight Relentless Perpetual Edge Knife.
10″ Straight Relentless Perpetual Edge Knife.

Curved – Designed for bigger fish like large Mahi and other more significant fish. Allows for a single cut to slab out the side of a fish. MSRP $219.99

9" Curved Relentless Perpetual Edge Knife.
9″ Curved Relentless Perpetual Edge Knife.

Straight – Our version of the traditional straight-blade knife that is known for maneuverability around fish spines and gills. Ideal for Grouper and bottom fish
with stout, complex spines. MSRP $219.99

8" Straight Relentless Perpetual Edge Knife.
8″ Straight Relentless Perpetual Edge Knife.

Curved – Ideal for the coastal fisherman for cleaning larger Mahi, Snapper and the like. Also, for the freshwater fisherman who prefers a larger knife. MSRP $209.99

7" Curved Relentless Perpetual Edge Knife.
7″ Curved Relentless Perpetual Edge Knife.

Curved – Designed for the freshwater fisherman and inshore saltwater fisherman. Also a good knife for cutting bait. MSRP $209.99

6" Curved Relentless Perpetual Edge Knife.
6″ Curved Relentless Perpetual Edge Knife.

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