Cutmore ProSharp Review: Adjustable-Angle Knife Sharpener

Cooking with blunt knives is no fun, is genuinely dangerous and damages your ingredients. Cutmore's ProSharp and OneSharp promise to make worn cutting edges a thing of the past, restoring knives of all kinds in seconds. Both pull-through sharpeners went through an extensive test.

The case for sharpening goes beyond effortless slicing. A blunt knife is more dangerous than a sharp one: forcing it through food invites slips and cuts, while a sharp blade gives control throughout the stroke. Food quality benefits too — a sharp edge severs cells cleanly where a blunt one crushes them. Onions are the obvious example: a blunt knife means streaming eyes and bitter, bruised flesh, while herbs lose their essential oils into the chopping board and meat and fish suffer crushed cell structure. Regular sharpening even extends a knife's life, since less material needs removing each time and the edge geometry survives longer. And a sandwich topped with paper-thin ripe tomato and finely chopped — not crushed — chives makes the difference deliciously obvious.

The blade should be clean and undamaged — grease and moisture impair the grind — and the sharpener needs a firm, level, non-slip surface. Good pull-through sharpeners let you choose the angle; quality knives state theirs on the packaging, and when in doubt, choose the larger angle and the gentler grind. The single most important thing is not speed but holding the same angle throughout: seat the knife centrally in the slot and draw it through from heel to tip with even, light pressure, never tilting, never sawing up and down, always pulling in one direction. After sharpening, a fine burr can remain on the edge — quality devices include a fine-honing slot to remove it, which is also worth running between full sharpening sessions.

These are sharpeners, not honing tools — an important distinction. Honing straightens the microscopically fine edge that folds over in use, removing no material, and only works while a knife retains basic sharpness. Sharpening removes material in a controlled way to build a new edge on a blunt blade — exactly what these pull-through devices do.

The grinding angle determines the balance between sharpness and stability, and every knife has its intended angle. Around 15 degrees per side characterises Japanese knives — sushi blades cannot be sharp enough, but such edges chip more easily and should be used strictly for purpose. 17-18 degrees is the established compromise for premium blades such as Damascus knives; 20 degrees is the standard for European kitchen knives, balancing sharpness with robustness and forgiving rougher handling; 22 degrees suits sturdier blades and cleavers; 25 degrees and beyond is for outdoor and hunting knives or hatchets. A stainless-steel angle gauge costs under ten euros if you want certainty about your own knives.

The ProSharp's exterior is entirely plastic but excellently made. The handle suits right and left hands equally for pinning the unit down, two rubber pads grip the worktop, and the flat build adds stability — under firm downward pressure nothing flexes, creaks or clicks. A large red wheel on top sets the sharpening angle of the tungsten-carbide unit: 15 degrees for delicate Japanese blades, 18 for Damascus and finely ground edges, 20 for classic European cook's knives, 22 for sturdier blades and 24 for outdoor and survival knives or machetes — with the manufacturer listing typical brands for each setting. Dedicated slots handle bread knives and scissors, plus a fine-honing slot for deburring after sharpening.

Tested against high-quality Japanese sushi knives, European cook's, utility, meat, vegetable and filleting knives, cheap no-name blades and outdoor and pocket knives, the results were very good to excellent across the board. Eight to ten pulls for the base grind plus a fine-honing pass — repeated two or three times for badly neglected blades — raised cutting performance dramatically. One extremely worn European cook's knife that could barely break a ripe tomato's skin sliced it paper-thin again after three rounds. With very blunt knives the first pass removes a lot of metal, visibly as filings and audibly as a grinding note that sensitive ears must simply endure; the payoff in the kitchen repays it many times over. Onions fall twice as fast, julienne succeeds flawlessly, and evenly cut ingredients even cook more evenly.

Two criticisms: the angle markings stamped into the red plastic could be easier to read, and when withdrawing blades you almost inevitably nick the plastic housing, so the device soon stops looking new. The angle question also deserves respect — sharpening a standard European knife at 15 degrees means heavy material loss and risks damaging the blade. Handled correctly, though, the ProSharp is little short of a miracle cure for blunt knives.

The cheaper OneSharp works differently: one slot, with a side wheel — the marketing calls it a revolver drum — that swaps the grinding unit and thus the mode. Sharpening uses tungsten carbide with a spring mechanism holding the angle, but fixed at 20 degrees, so it suits European cook's knives, bread knives and scissors only — not Japanese or fine professional blades. A resin-diamond care mode maintains the edge every few days, a ceramic fine-honing mode removes burrs after every sharpening, and dedicated ceramic and hard-diamond settings cover serrated bread knives and scissors. The same robust plastic construction, rubber pads and squat stability apply — and the same unavoidable nicks in the housing over time.

The ProSharp earns an emphatic recommendation: adjustable angles from 15 to 24 degrees make it safe for everything from sushi knives to outdoor blades, and the test results were excellent throughout. The OneSharp is the sensible budget pick for households whose knives are all European 20-degree standard — same build quality, simpler scope. Either way, mind the angle, accept the cosmetic battle scars, and enjoy knives that glide through tomatoes again.