Hacker News Board Hacker News, browsed like a classic message board
Live data from Hacker News

Ultrasonic Chef's Knife

seattleultrasonics.com

Post reply on HN
Print view View original

551–560 of 697 posts

Re: Ultrasonic Chef's Knife

#551

Post by [deleted] »

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.

[deleted]

Re: Ultrasonic Chef's Knife

#552

Post by herpdyderp »

dlcarrier wrote: post #352
Taek wrote: post #243

I'm a bit surprised to see how much snark there is in the comment sections of this video. The requests for "let's see an independent chef use this knife to do real kitchen work" make total sense, but the moralizing around e-waste and losing fingers etc feels off balance. People spend hundreds of dollars and many hours sharpening kitchen knives, of course there's a viable market for sharper kitchen knives. And for e-w…

>People spend hundreds of dollars and many hours sharpening kitchen knives... What amazes me is how many people spend absolutely zero time sharpening knives, using decades-old knives that have never been sharpened and can't even cut through cucumbers.

I've tried sharpening knives a few times in my life and I've never been able to tell the difference. I agree with the principle, but in practice I simply haven't witnessed it matter.

Re: Ultrasonic Chef's Knife

#553

Post by idiotsecant »

herpdyderp wrote: post #552
dlcarrier wrote: post #352

Earlier quoted context omitted.

>People spend hundreds of dollars and many hours sharpening kitchen knives... What amazes me is how many people spend absolutely zero time sharpening knives, using decades-old knives that have never been sharpened and can't even cut through cucumbers.

I've tried sharpening knives a few times in my life and I've never been able to tell the difference. I agree with the principle, but in practice I simply haven't witnessed it matter.

I think you might be bad at sharpening knives. There is no shame in that, almost everyone is very bad at it, it's difficult to do it properly.

Re: Ultrasonic Chef's Knife

#554

Post by amluto »

Aardwolf wrote: post #452
petepete wrote: post #426

Earlier quoted context omitted.

Were you cutting tomatoes with a serrated knife? If not, you should be - they do a far better job.

Can one even sharpen a serrated knife without destroying the teeth? Google search autocomplete shows I'm not the only one wondering that

It’s kind of tedious, but you can do it with a tool like the DMT Diafold Serrated Knife Sharpener. On most serrated knives, you will also want to lightly sharped/deburr the other face at an extremely shallow angle using a whetstone that either you don’t care about too much or that is extremely resistant to scratching (e.g. a DMT-style flat stone). If you do that part on something like a traditional Japanese stone, you will make a mess.

Re: Ultrasonic Chef's Knife

#555

Post by mapt »

an_ko wrote: post #464
dlcarrier wrote: post #352

Earlier quoted context omitted.

>People spend hundreds of dollars and many hours sharpening kitchen knives... What amazes me is how many people spend absolutely zero time sharpening knives, using decades-old knives that have never been sharpened and can't even cut through cucumbers.

Such people should perhaps consider a ceramic-bladed knife. They stay sharp basically forever because the blade is extremely hard, with the downside that it's not repairable with ordinary equipment if chipped. But if the owner would never maintain their metal knife anyway, then it's not _really_ a downside.

They do not stay sharp.

On hard material and when overloaded, they will chip in large, unfixable chunks.

On softer material, they continuously sharpen their edges at a microscopic scale, fracturing away tiny chips as they're worn, to new glassy ceramic molecular edges. A well used ceramic blade becomes micro-serrated.

This sounds fantastic until you think about what is happening to the shards of hard glassy ceramic which briefly become part of your food before becoming part of your gastrointestinal tract.

Re: Ultrasonic Chef's Knife

#556

Post by kleiba »

idiotsecant wrote: post #553
herpdyderp wrote: post #552

Earlier quoted context omitted.

I've tried sharpening knives a few times in my life and I've never been able to tell the difference. I agree with the principle, but in practice I simply haven't witnessed it matter.

I think you might be bad at sharpening knives. There is no shame in that, almost everyone is very bad at it, it's difficult to do it properly.

> almost everyone is very bad at it

[citation needed]

It's more that sharpening a knife - like many other skills - takes practice.

Re: Ultrasonic Chef's Knife

#557

Post by blincoln »

john_minsk wrote: post #373
temp0826 wrote: post #328

Earlier quoted context omitted.

Maybe instead of building it into the knife, it needs to be something you could attach to any knife

Interesting idea, but I would say that it is orders of magnitude harder compared to having an integrated system. Vibration in such a compact space with a very sharp blade... I want this system be stable around me. I would say, if this idea becomes popular, knife producers can create their own versions in the new models, or retrofit old knives at the shop.

Yeah, I'm already somewhat skeptical of the whole concept, having DIY'd a vibroblade out of an X-acto knife and a SonicCare toothbrush and finding it to be completely ineffective.[1]

I think trying to make an ultrasonic vibration add-on for regular knives would be even harder to make into a useful product than an integrated knife/transducer.

If the handle is rigidly fixed to the blade, there would be very little vibration. So it seems like the only way to make an add-on would be as a sleeve over the regular handle. That would make for a bulky handle, and it seems like it would need a counterbalancing weight at the back. So the result would be very unwieldy, like one of those electric turkey-carving knives that are basically kitchen hedge-trimmers.

I'm waiting to see what skilled chefs think of this knife. The idea of an ultrasonic vibroblade has always seemed like a neat one to me, and I'd be happy to hear that someone managed to make one that was genuinely useful.

[1] https://www.beneaththewaves.net/Projects/SonicCarereg_Lock_P...

Re: Ultrasonic Chef's Knife

#558

Post by ec109685 »

bryanrasmussen wrote: post #445
john_minsk wrote: post #366

Earlier quoted context omitted.

I don't use knives in my kitchen. My romantic partner does. Yesterday I decided to cut some tomatoes only to find out that all knives are dull. She never said anything, I didn't know it. Why? Because she is just "used" to it and to her these knives were just fine. So she never thought about sharpening knives in the first place. I will take those knives to a pro and he will sharpen them for me, as in a rental I stay i…

>I don't use knives in my kitchen. How do you not use knives? Do you use some other cutting instrument, that has the same problem as knives (cutting edge needs sharpening at times), do you only purchase pre-sliced food, do you only order take out, or only eat food that never needs cutting, or do you eat food that many or most people would cut in some way (oranges, apples, celery, etc.) by refusing to cut but using yo…

Their partner does all the cooking.

Re: Ultrasonic Chef's Knife

#559

Post by tdeck »

herpdyderp wrote: post #552
dlcarrier wrote: post #352

Earlier quoted context omitted.

>People spend hundreds of dollars and many hours sharpening kitchen knives... What amazes me is how many people spend absolutely zero time sharpening knives, using decades-old knives that have never been sharpened and can't even cut through cucumbers.

I've tried sharpening knives a few times in my life and I've never been able to tell the difference. I agree with the principle, but in practice I simply haven't witnessed it matter.

I've had the same experience with the pull through sharpeners, but I bought a cheap 2-sided Japanese waterstone and learned to use it (not very well) and the difference it makes is very noticeable despite my lack of skill. It does however take me maybe 15 minutes to sharpen a knife.

Re: Ultrasonic Chef's Knife

#560

Post by ec109685 »

YeGoblynQueenne wrote: post #511
john_minsk wrote: post #366

Earlier quoted context omitted.

I don't use knives in my kitchen. My romantic partner does. Yesterday I decided to cut some tomatoes only to find out that all knives are dull. She never said anything, I didn't know it. Why? Because she is just "used" to it and to her these knives were just fine. So she never thought about sharpening knives in the first place. I will take those knives to a pro and he will sharpen them for me, as in a rental I stay i…

>> I will take those knives to a pro and he will sharpen them for me, as in a rental I stay in, I don't have the tools to do that and as I said in another comment - I don't have a pain free process to do that as I don't do it often Do you also replace your elderly relatives' Windows XP with linux distros, because linux is a better OS? The moment you return the sharpened knives to your partner and she starts using the…

Eventually they will be exposed to sharp knife’s, so probably good to ease their way into it.
Post reply on HN