Work Sharp Ken Onion Edition Knife & Tool Sharpener Review

A Versatile Sharpener At a Reasonable Price

The Ken Onion Sharpener is probably the single best knife sharpener out there for consumers and chefs. This smartly designed electric sharpener can handle an amazing array of knives and blades. It comes with angle guide that’s easily adjustable from 15° to 30° using a simple turn of the dial.

Or you can remove the angle guide to sharpen scissors at 65° angle. And without the angle guide, you can point the sharpener at any blade, allowing you to sharpen things like hatches, axes, and mower blades, too. It can even do pizza wheels.

It uses belts that make a slightly curved convex edge rather that a flat edge produced by rigid wheels and other sharpeners.

For most blades, you sit the unit on a countertop, dial in the angle, select a belt, and start by pulling the trigger on the handle, just like on a chainsaw. Then you run each side of your blade through a series of coarse to fine sandbelts. Changing belts takes only seconds. The sharpener comes with 5 durable sandbelts: P120 extra coarse, X65 coarse, X22 medium, X4 fine, and micro mesh 6000 extra fine. When the belts wear out, a replacement set costs only about $14.

To help you determine blade angles, sandbelt fineness, and the number of strokes to use, the product packaging comes with a user-friendly quick start guide. You can also scan a QR code to watch a short video online, which I recommend doing the first time to familiarize yourself with the sharpener and how slowly you should run your blades through it, which is pretty slow (1 inch of blade per second).

The motor speed is adjustable from 1,200 to 2,000 SFM (surface feet per minute, a measurement of both diameter and velocity) so you can use an appropriate speed for the blade you are sharpening. Low speed is recommended for kitchen knives and high speed for tools. A toggle button on the handle makes it a cinch to hold a steady speed.

Before working on my kitchen knives, I sharpened my trusty old Kershaw Vapor 1640 pocket knife, which was dull and neglected. The quick start pictures recommended a 25° angle, but you can adjust the angles anywhere between 15 and 30° on the angle guide, so I tweaked it to a slightly sharper 22.5°. I ran the 3-inch blade through 3 sanding belts, and it got razor sharp in a few minutes with minimal scratches on the side of the blade.

From there, I sharpened all my kitchen knives from 12-inch long French chef’s knives and 6-inch Japanese santokus to paring knives, utility knives, slicers, and Chinese cleavers. Yes, it took a while, but they all cut cleanly now. I am very happy. See the test results below.

What I like most about this sharpener is the bang for the buck. It costs less than most other electric sharpeners (I own several) and is even more versatile. For a little over $100, you can use it to sharpen almost every blade you own. And you can dial in your angles with ultimate precision. You will notice that the unit is made with some cheap plastic parts here and there, but those are replaceable, and the motor is rock solid.

The sharpener ships in a simple cardboard box smaller than a shoebox, where you can keep it stored along with the instructions and sanding belts. The whole thing is fairly lightweight, so I brought the box to my friend Mike’s house and sharpened his kitchen knives as a favor for doing some electrical work for me. He was pretty impressed. With shop tool styling, this sharpener is a reliable workhorse in both the workshop or the kitchen. Warranty: 1 year household warranty on defects due to workmanship and design, excluding abrasives.

Tomato and onion: Easily cut thin slices

Carrot tops: Easily removed with one stroke

Foam peanut: Easily cut a thin slice

Paper: Easily cut several clean slices with no grabbing

How To Use It

We strongly recommend you view a few videos on the devices proper use and read the manual before getting started. The concepts are pretty simple, but if you just dive in you can destroy a blade. Here is an intro video. Here is a video with more detail. Here is how to do pizza wheels, rotary cutters and even razor blades.

1. Putting a belt on is a bit tricky. Slip it over the bottom wheels first, press the springloaded wheel, and slip it over the top.
2. Select a belt. For most work you need only two, the P120 coarse belt first, and then the X4 fine next.
3. Put on your safety glasses.
4. Select an angle.
5. With the machine off, place the knife in the guide with the bolster end at the edge of the belt.
6. Set the speed for medium, pull the trigger and press down with light pressure.
7. Drag the blade through at 1” per second.
8. Keep the edge perpendicular to belt. Rotate curved blades to stay perpendicular.
9. Let go of the trigger when the tip is in the middle of belt.
10. Do two pulls on side one. There should be a burr that you can feel on the opposite side. If not, two more pulls.
11. Switch sides and do two pulls on side two.
12. Go back to side one for two more pulls, then the other side, then side one, then side two for a total of three reps of two pulls per side.
13. Now switch to the X4 belt and do two pulls per side. Clean the blade and you’re ready to go.