Mueller Ultra-edge Electric Knife Sharpener In-depth Review

Mueller is a household brand known for its affordable products. The brand produces both handheld and electric sharpeners and can be easily recognized by their robust, red-and-black plastic body, and stainless steel housing. We’ve tested both types of sharpener, and neither makes it to the top choices. 

We wanted this Mueller electric sharpener to work. It’s pretty, well-built, and is literally the coolest and quietest electric sharpener we’ve got our hands on up to date (February 16, 2023). It’s also very easy to use. 

Unfortunately, the sharpener did a subpar job in speed and sharpness and didn’t produce a very nice edge. It’s also a little selective of the types and lengths of blades it could take in. 

Here are the details of what we found during our tests with the Mueller electric sharpener.

5.4 Performance

The Mueller Ultra-edge didn’t produce an ultra edge in our tests. It failed miserably in the speed test and produced a mediocre edge height. On the other hand, it shaved off less blade material than most other electric sharpeners. The machine also managed to work without issues when facing the task of sharpening several knives in succession.

1.0 Speed

The Mueller Ultra-edge Electric Knife Sharpener didn’t pass our speed test: It took a few forceful swipes to cut through beef tendon after more than 10 minutes of sharpening. While this keenness is good enough for most cutting tasks, we expect more from an electric sharpener. 

For your reference, other electric machines take half the time (about 5 minutes) on average to complete the test, with the test knife cutting through beef tendon in one single swipe.

6.0 Edge Quality

Sharpening at 20 degrees, the Mueller KSE-24 produced a narrow knife edge with uneven bevels. At this edge height, the knife will struggle with thick and dense food materials. 

The new edge looks straight and smooth in person, so we were surprised to find the inconsistencies in the magnified photo. This means the knife had experienced irregular upward and downward forces as it was pulled through the slot, even though we couldn’t feel it. This must have reduced the sharpness, though the difference would be minimal in this case.

7.0 Material Retention

Judging by the small edge bevels it produced, it’s no surprise that the KSE-24 didn’t remove a lot of material from the blade. But neither did the Narcissus or WorkSharp CPE2, and we could get a much keener edge with either one.

10 Continuous Operation Time

The instruction manual claims that the Mueller can run continuously for 60 minutes. Throughout our 25-minute test, there was no single instance of stalling or stopping. The machine ran smoothly and consistently. It was still very cool to the touch at the end of the session. Those who tend to sharpen multiple knives at once will appreciate this.

6.3 Design: Neat and Strong but Lacks Versatility

The Mueller electric sharpener has an attractive design with sleek stainless steel over a black-and-red plastic housing. It’s heavyweight and sturdy.

Like most others, however, it only sharpens at a set grind angle, which is not ideal for specialized kitchen knives such as filets or cleavers. The machine is also not designed to handle serrated knives.

In the Box

• The Mueller Ultra-edge KSE-24 electric knife sharpener
• Instruction manual
• Promotional leaflets 

The KSE-24 comes in a neat cardboard box with its manual book. The instructions are only available in English.

Weight & Dimensions

Power Cord

8.0 Build Quality

Despite its affordable price, the Mueller seems to be built to last. It’s made with solid materials and all the parts fit together sturdily and seamlessly. We like the stainless steel plates covering its body, which gives it a modern look and keeps cleanup simple. The power switch is basic but intuitive.

1.0 Angle Adjustability

The KSE-24 sharpens at a fixed grind angle of 20 degrees. This works for most Western kitchen knives, but it may not be a good idea to sharpen Asian knives with this machine.

8.0 Knife Size

The Mueller electric sharpener works pretty well on all of the knives we tested it with. However, there are occasions where the abrasives didn’t ‘touch’ the blade. This happens more often on thinner knives and may cause uneven edge texture, but not to an alarming frequency.

5.0 Edge Type

The KSE-24 does not sharpen serrated knives. That being said, if you have cheap serrated knives that are already so blunt the only other option is to throw them away, you could sharpen them on their flat side using the fine slots.

8.4 Ease of Use: Fuss-free Operation

The Mueller Ultra-edge is straightforward. A newbie could set it up and start sharpening without issues. It also got a higher safety rating from us than any other electric sharpeners we’ve tested, doing well in temperature, noise level, and dust control.

The brand guarantees “life-time customer satisfaction,” and we haven’t had the unfortunate chance to contact them over a faulty product. If something goes wrong or is broken, as far as we can see, the only option is to give their service center a call. We couldn’t find replacement parts online.

9.0 Setup

One of the great things about electric sharpeners is how easy they are to set up, and this Mueller machine is no exception. You place it on a table, plug it in, switch it on, and start sharpening. 

The unit is heavier than most and may not be very convenient to carry around, but it also has one of the longest power cords of all electric sharpeners we’ve tested.

8.0 Insertion

The Mueller’s slits don’t have the same design as those you’d find on your typical electric sharpener. Instead, they look more like those on a manual handheld sharpener—particularly on the Chef’s Choice 4643. They’re quite narrow, making it easy to cut into the guides, but as long as your hand is relaxed, blade insertion would be fairly easy with this one.

9.0 Stability

With its heavy weight and sturdy design, the Mueller stood firm through the stability test. The inconsistent knife edge texture indicates that there might have been some juggling at the abrasive wheels; however, we didn’t feel it.

8.8 Safety

We gave the Mueller KSE-24 the highest safety rating among all the electric sharpeners we’ve tested. Even after 25 minutes of continuous sharpening, it managed to stay only slightly warmer than room temperature! Although the noise level is comparable to an average hair dryer, the machine is one of the quietest machines we’ve worked with.

With its deep, narrow slots, most of the sharpening residue falls right down and sticks to the magnetic plate underneath its abrasive wheels. We still recommend wearing a mask when sharpening to be on the safe side, but at least there was much less visible dust around the machine compared to the Presto EverSharp or the Ken Onion.

5.5 Maintenance

Judging by its sturdy construction, we believe the sharpener will last a long time. Mueller guarantees life-time customer satisfaction for the KSE-24. However, should any parts stop working, it’d be nice to be able to find replacement parts online, which we couldn’t.