Cubikook CS-T01 3-Stage vs. Mueller 4-Stage Manual Sharpener Side-by-Side Comparison

The Mueller isn’t the speediest of sharpeners, but it works fast enough. We put it through the lemon test twice, and it took 60 and 90 seconds respectively to complete the task. This is quite a reasonable time range, considering how dull we made the knife before testing.

Skipping the diamond rods won’t affect the result. We only used them to rid the knife edge of metal particles and make sure it was as smooth as it could be, but if you’re in a hurry, the ceramic rods alone would suffice.

The Cubikook does a quick job of bringing life to a dull blade. After only 90 seconds on the device, our sandpaper-destroyed test knife could cut through a lemon with one swift draw. This placed the Cubikook in the top tier of pull-through sharpeners in terms of speed.

Most kitchen knives should see improvements after about 30 seconds on the second slot.

After 5 minutes on Slot 2 and 30 seconds on each of the remaining slots, our test knife was able to cut through a raw chicken breast with the skin still attached. It did need a second swipe to sever the tough, slippery fat and skin, but this is the case for most devices.

After 6 minutes of sharpening, the test knife could cut through a fresh piece of chicken breast with the skin still on. The gristly fat under the skin kept running, but we managed to sever it with a little effort. 

We tried the knife on a piece of raw beef tendon (Level 9) and it took two forced swipes, so we decided it hadn’t progressed beyond a sharpness level of 8.

The Mueller is a disappointment when it comes to preserving edge integrity. We were horrified at the size and amount of swarf the sharpener churned out after every swipe on the tungsten carbide blades. It’s all or nothing with this slot: When it works, it shaves off as much metal as it can. When it doesn’t, your knife simply glides through it, untouched.

The icing on the cake is the obvious unevenness on the two sides of the edge. We can’t quite work out the reason for this, because its sharpening slots look exactly the same as the Longzon, which created a very nice edge in our test. We re-edged the test knife and tried again, and even replaced the test knife in case it was a faulty one, but the end result was the same.

While effective, the Cubikook doesn’t remove a lot of material. This is one of the advantages multi-stage devices have over single-stage ones such as the Sunrise Pro. The first stage (diamond-impregnated rods) helps straighten the edge before you put it through the tungsten ‘peeler’ stage. Finally, the third, ceramic stage acts as a final honing step to leave your blade as smooth as possible. 

The benefit of single-stage devices is that they sharpen your knife quicker. That’s possible because they simply pull off more metal at a time. That means your knife will get eaten up faster, so you have the choice between quick sharpening or long overall blade life.

The diamond dust and ceramic rods didn’t seem to do much if anything to smoothen the edge: It came out rough with waves and small chips all across its length. I could see it with my naked eyes and feel the chips and small particles as I ran my fingers along the edge. The discrepancy between the two sides just tops it off.

The Cubikook creates a smooth edge. It came out looking much better than many single-stage and even multi-stage versions like Smith’s 50264 or Chef’s Choice ProntoPro. In fact, we scored this device better on the edge smoothness test than any other we’ve tested to date. It creates the straightest line with barely any visible chips, while the grooves on the primary edge were also even and narrow.

This fine edge is the result of good design choices. The device’s working section is placed low and fastened tightly to the base, which helps distribute pressure evenly against the delicate edge regardless of how much force is applied. The ceramic rods in the final stage help remove any remaining burrs or metal particles, thus minimizing edge deformities.