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Ultrasonic Chef's Knife

seattleultrasonics.com

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Re: Ultrasonic Chef's Knife

#521

Post by IanCal »

lazide wrote: post #482
thom wrote: post #470

Earlier quoted context omitted.

We moved house recently and I bought some new knives for the kitchen. My wife is now constantly cutting herself because she has no intuition for how sharp a knife should be. I can’t really imagine what the safety argument is against dull knives.

A knife which cannot cut anything isn’t a knife? It sounds like she literally has no idea how to use a knife. Is she doesn’t want a knife which can cut things, Butter ‘knives’ are probably more her speed? What was she even using the ‘knife’ for before if it couldn’t even cut her? Spreading jelly? Slicing cakes? Not to be snarky, but it’s possible a couples class which covers things like how to use a knife safely migh…

Have you never used a knife like this? I’ve got one that’s been used by people on plates enough that it’s dull - I can press it into my fingers and pull back and forth and it won’t cut me with pretty reasonable pressure. With more pressure if it’s a glancing thing it’ll not take off a knuckle. I’ve just used it so that I could say this but chopping up a cucumber is totally fine and easy. I can’t cut like I can with my actually sharp knife but it’ll cut stuff.

Re: Ultrasonic Chef's Knife

#522

Post by soegaard »

thom wrote: post #470
RHSeeger wrote: post #411

Earlier quoted context omitted.

I know I'm setting myself up for being picked up, but... I use an older knife that I've never sharpened outside of "occasionally" running it back and forth against a tough fabric. It cuts literally everything just fine; cucumbers, tomatoes, potatoes, etc. Nothing about my use of it _seems_ unsafe; but I expect that's partially because I don't cut very fast. Cooking, when I'm involved, tends to be "social time", where…

We moved house recently and I bought some new knives for the kitchen. My wife is now constantly cutting herself because she has no intuition for how sharp a knife should be. I can’t really imagine what the safety argument is against dull knives.

When a large force is applied unintentionally to a finger we have the problem. With a dull knife you need to apply a larger force than with a sharp knife. [The video illustrates this with breaking the skin of the tomato.] For a normal cut this is not a problem.

But - if the knife slips and a large force is applied at the same time - then you will get a large cut.

If the knife slips and a small force is applied, you will get a smaller cut.

If the probability of slipping is the same for sharp and dull knifes, then due to the forces applied, the cuts you get with a sharp knife are less dangerous.

Re: Ultrasonic Chef's Knife

#523

Post by YeGoblynQueenne »

9x39 wrote: post #288
wisty wrote: post #246

Why is it people here seem so unusually sceptical? It's expensive (but not really, only compared to knives - a $500 GPU isn't expensive). It's probably mostly good in certain niches and using a $10 knife that's sharpened properly is probably 95% as good in almost every application, and using a $10 knife that is only reasonably well sharpened is probably 90% as good. Slicing stuff for hotpot or yakiniku or Korean BBQ…

I think it's because it seems like a Juicero to anyone who uses knives to make dinner regularly. We're fascinated by tech, and sure, I'd try this, but I bet anyone who has prepped with a knife for hours per week is probably pretty skeptical on the practicality here. A sharpened piece of metal has been reliable for thousands of years and will continue to remain so. For new tech, I am also a fan of the ceramic knives o…

"You gonna have an exciting life now. Breakfast to go. You're gonna love my nuts".

O.o

Re: Ultrasonic Chef's Knife

#524

Post by IanCal »

rkomorn wrote: post #471
thom wrote: post #470

Earlier quoted context omitted.

We moved house recently and I bought some new knives for the kitchen. My wife is now constantly cutting herself because she has no intuition for how sharp a knife should be. I can’t really imagine what the safety argument is against dull knives.

Maybe there's some bell curve of knife skills proficiency where the better you are with knives, the safer they are when sharp, but generally: Dull knives are more likely to slip on whatever you're cutting (and cut you instead). They're also more likely to need more force when cutting which means less control.

People say this a lot but the dull knives I have won’t cut my hands around the force required to cut, say, veg. My sharp knife will cut my hand at extremely low levels of force. Also the direction the dull knives can slip is usually along the surface of what I’m cutting which would almost always be away from my hand.

Re: Ultrasonic Chef's Knife

#525

Post by YeGoblynQueenne »

non_aligned wrote: post #130
appcustodian2 wrote: post #87

Earlier quoted context omitted.

just want to point out that maintaining a knife is a whole hobby that requires a time investment of learning the skill and storage of additional tools and materials. i'm surprised at all the apparent knife enthusiast posts trashing this device. I take my victorinox (which is absolutely nothing special and surprises me that it costs $60+ dollars) to the farmers market for sharpening but sharpness isn't even the proble…

> just want to point out that maintaining a knife is a whole hobby that requires a time investment of learning the skill and storage of additional tools and material. You're right that's a hobby. But the hobby's definition of "proper maintenance" and what it "requires" is basically just people nerding out about things that don't matter the slightest in the real world. To maintain a kitchen knife so that it cuts a tom…

Also: use serrated knives for tomatoes. They don't squish.

Re: Ultrasonic Chef's Knife

#526

Post by Saline9515 »

athoscouto wrote: post #508
Saline9515 wrote: post #507

Earlier quoted context omitted.

Duller knives cut more slowly, hence if I cut my finger, I feel it before it goes deeper, which is safer. Such knife seems like a disaster waiting to happen, I can't see the benefit honestly.

I've seen chefs arguing the other way around. You have to apply more pressure when using duller knives, this means less control and less safety.

I agree, but this is more about stopping when you get hurt. I cook everyday and hurt myself only with very sharp knifes as I couldn't feel when the knife was about to cut my skin.

Re: Ultrasonic Chef's Knife

#528

Post by rkomorn »

IanCal wrote: post #524
rkomorn wrote: post #471

Earlier quoted context omitted.

Maybe there's some bell curve of knife skills proficiency where the better you are with knives, the safer they are when sharp, but generally: Dull knives are more likely to slip on whatever you're cutting (and cut you instead). They're also more likely to need more force when cutting which means less control.

People say this a lot but the dull knives I have won’t cut my hands around the force required to cut, say, veg. My sharp knife will cut my hand at extremely low levels of force. Also the direction the dull knives can slip is usually along the surface of what I’m cutting which would almost always be away from my hand.

I guess it depends on how dull your dull is.

The knives I consider dull will absolutely cut me if I do something dumb, and I'm much less likely to do something dumb when the blade goes straight through what I'm cutting without having to use any force.

I guess it also depends how and what you're cutting. I sure wouldn't try to julienne carrots with a knife that doesn't easily slice through the carrot.

Re: Ultrasonic Chef's Knife

#529

Post by spragl »

It is a cool product, but I have the clumsiness of the average home cook. So my old style knifes are plenty sharp for me. I would not be comfortable using this. But if there were a version with the slipperiness he shows, just having standard sharpness, it would be much more interesting to me.

BTW I think the focus on knife sharpness is overrated for most kitchen tasks. At least for home cooks. Your knives should just have the necessary sharpness. More than that is a negative in my opinion.

Re: Ultrasonic Chef's Knife

#530

Post by mensetmanusman »

9dev wrote: post #432
mensetmanusman wrote: post #325

Earlier quoted context omitted.

E-waste can be solved without reducing the number of items. Just requires basic investments in recycling.

Recycling is a sham. There is mostly no efficient recycling of sufficiently advanced components, the industry just spent decades on making you think you can buy lots of cheap things and all that trash isn’t your problem. Well it is.

With enough energy we can separate anything into its elemental constituents.

“Recycling” as mentioned by the US press is a scam because we had humans walking over our trash in India manually recycling in such a dangerous way they banned our recycling.

Anything can be ground into dust and sent through a series of physiochemical processes to reconstitute.

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