QVC might not be a well written takedown of it, but he’s right that you don’t need an electronic knife.

My first job was at a knife shop so I’ve seen everything from stamped steel fantasy nonsense to traditional style hand forged items. There’s a lot that goes into making a good knife and you don’t need to spend a lot to get one. Similarly you can spend a lot of money for marginal to no benefit.

In general a hard edge with a softer back is necessary for a strong knife that will cut well. This is a function of heat treatment. A knife that is tempered the same the whole blade is fine for smaller knives but it’s possible to break the tips or edges off larger knives. From there metallurgy affects the edge retention and how easy it is to sharpen. Plain 440C will make a fine enough knife if heat treated properly but can also make blades that can’t be made particularly sharp and can’t easily be sharpened. These knives will be very stainless so this is why poor quality and good quality knives will be made in 440C. The next tier of knives beyond singular steel forging will be a very hard edge steel wrapped around a softer core steel. The sky is the limit from there in terms of metallurgy. The highest end knives will use powdered steel where precisely composed steel bars are made using uniform grains of steel and other attractive metals and doping materials as part of the forging process.

Once it gets home a good edge has to be maintained.

People do all sorts of things to dull perfectly good cutlery (I cringe when I see people use glass or marble serving/cheese boards as a cutting board). A off hand toss of a knife into a sink can roll the edge.

The worst offense is when I see someone at a farmers market with the grinding wheel “sharpening” a knife by crudely removing the hardened steel edge of a knife. Good luck cutting much with the softer core steel or softer tempered back steel.

While having an Evangelion style ultrasonic knife is cool, it’s certainly not necessary and I expect it can be ruined in many of the same ways a $400 traditional knife can be.

At home I have Henkels for the holidays and some forged food service knife’s for general use. When visitors throw the food service knives into the sink I just take out the sharpening stones and don’t cry all that much.

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crazygringo 8 hours ago | parent [-]

Literally everything you've said is about regular knives. You haven't said a thing about ultrasonic knives. So I'm not sure what you're trying to argue?

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Moto7451 8 hours ago | parent [-]

Knives are already high tech and the GP’s point that you don’t need an ultrasonic knife is valid even if “QVC product” is inaccurate. They’re not just hunks of steel. Sharp knives can be dulled by abuse which something that vibrates will be vulnerable to as well.

This is akin to the already established very expensive powdered steel knives. Do you need this to have a sharp knife? Nope. Is anyone wrong for wanting it? No.

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crazygringo 8 hours ago | parent [-]

This product isn't about not having to sharpen your knife.

It's about a knife that is ~equivalently sharp to begin with, but slices with less force and less sticking, and can therefore slice things more exactly/easily than otherwise.

Of course you don't need it, but it's fundamentally different from existing knives, which you seem to not be acknowledging. When you say this is akin to "powdered steel knives", no it isn't. Powdered steel is about hardness. Nothing to do with ease of slicing or lack of sticking.

So you're talking about things that have nothing to do with this particular technology.

	▲	Moto7451 4 hours ago \| parent [-]
		I’m not taking a negative view on this knife or technology. I believe you’re misunderstanding the intention of my color commentary? “Do not need” is not equivalent to “this is terrible.” Powdered metallurgy, to parry your point, is not about hardness but about having the most precise composition of a metal. I.e you can have better wearing 440C, better machinable 440C, etc. most of this was intended for manufacturing high end industrial equipment. For kitchen knives it’s unnecessary even if it’s cool. It’s incrementally better but like this product it’s not necessary. Similarly this isn’t “new technology” aside from the packaging of industrial technology into a chefs knife. You can get X-Acto knife sized versions of this already. Ceramic blades came from industrial alumina production. Cool, not necessary, but nothing wrong if it’s your jam. The classic “QVC knife” is the Ginsu knife which has a lot of the same claims/qualities from a far. It’s an implementation of pattern welded steel and when you use a microscope you’ll see its thousands of serrated edges. Their ad shows the user cutting a can and then thinly slicing a tomato. Works fine until the edge gets rolled and since it’s cheaply processed steel (lacking the points of good construction I mentioned above), that’s usually what happens. I’d expect the company this whole discussion is about doing a lot better here since they’re not trying to sell a three knife set for $29.95 with free shipping. My point about things being easily damaged with mishandling is that most people simply don’t handle knives well enough to see a benefit from high end knives, not that they aren’t nice/better/valid/different/etc. All of that can be true and the knife no longer cut because the edge is damaged. A Ferrari is a technologically complex car but not a very good car if the tires are all flat. If this thing doesn’t have an edge it isn’t going to cut well. This is a point they make on their own site: > Is the knife dishwasher safe? > Updated 13 days ago > > No, but neither is any sharp knife. Dishwasher detergents contain micro-abrasives that dull and chip away at knife edges. If you enjoy using sharp knives, never put them in the dishwasher! This is actually a more strict take than I have on edge retention, but I wouldn’t complain if my cutlery were treated this way. Like I said a few posts up, I have knives that cost several hundred dollars. I keep the cheap ones out so I don’t cry when they get lobbed into a sink with the dirty dishes. When sharp they all cut very well. The expensive ones are better at edge retention and can be made a little sharper. After a friend helps clean or cuts some cheese on the cheese board the knife that was used is dull and not a great tool, be it the $30 food service knife or the $400 Henkels knife. You just can’t cheat physics.