Seattle Ultrasonics: Ultrasonic Chef's Knife
48 comments
·September 20, 2025SoftTalker
dperfect
… and learn how to use it properly.
The tomato comparison in the video shows the unpowered knife trying to cut straight down through the tomato. That’s not how you should use a knife! Instead, you have to use some sliding motion, which subjects the thing being sliced to more of the cutting edge. In a way, it’s similar to what the ultrasonic knife is doing, but it requires no batteries or extra expense!
grues-dinner
In particular, you don't need expensive stones, guides or lapping systems to do it. An aliexpress-grade 3000/8000 waterstone, a flattening stone and a strop will get most knives shaving the hairs off your arm for under £20 all-in.
wffurr
The odds I will ever learn to use a waterstone or strop are nil. A Chef’s Choice manual sharpener is really easy and makes my knives plenty sharp enough to cut tomatoes.
runekaagaard
I agree. The industry standard for a great, boring, durable and surprisingly cheap knife is the Victorinox Fibrox Chef's Knife 20 cm.
dsr_
It certainly would be nice to have three or four independent reviews from people with knife skills.
jmarchello
We made it! We’ve finally invented vibroblades!
trhway
the next version will come with plasma micro jets ejection from the cutting edge - convenient for civilian use. I'm also wandering about an array of shaped micro-charges on the edge - should be able to cut through several millimeters of steel in one move, etc. so a soldier can cut though an opponent's ballistic vest or a into an lightly armored IFV.
bombela
Hard to watch the tiny video. Cannot be made full screen. Rotating phone sideways the website header obscures the video.
YossarianFrPrez
Maybe I'm just a sci-fi nerd who loves innovation, but this is so cool!
Clearly, this product is not intended for the mass market, and may find purchase with people who have tennis elbow and who can afford it, etc. <insert other critiques about practicality and applicability here>. But still, when was the last time someone tried to re-invent something as basic as a knife?
cjbgkagh
Ultrasonic knives are used commercially, this is an attempt at a mass market by making it cheaper and packaging it in a more familiar form.
onlypassingthru
> when was the last time someone tried to re-invent something as basic as a knife?
A year ago? This one is designed for woodworkers.
https://www.bourbonmoth.com/shop/p/the-bourbon-blade-origina...
Tade0
I would get this for the same reason I'm planning to replace my couch with an optimal-for-moving-through-a-turn couch as soon as I find a carpenter willing to make it. The middle part will be evened-out by a separate, round cushion.
tianjerry
This is the best demo video ever! Congrats on reinventing the knife!
ginko
Yeah, have to say the video is pretty good. I came in expecting the typical shopping channel pitch, but it did a very good job explaining the things the knife can and can't do. It really helps that it's presented by the inventor himself.
Still won't buy one but still.
whyenot
A good quality well sharpened knife already works incredibly well, doesn't cost $500, doesn't need to be recharged, and isn't going to be e-waste in 5 years (when the battery fails).
It's a cool idea, and I hope it is commercially successful, but not for me.
karmanGO
The battery is comes out for recharging, so replacing a dead battery should be trivial
scrlk
It's a proprietary form factor, so you're gambling on replacements being available down the line. I don't think it'll be easy to rebuild the battery pack without compromising the casing.
Zak
Given the battery specs and the form factor of the products, they could have used a 14500 cell that retails for $5. That's not as much recurring revenue as charging $80 for something proprietary though.
fumeux_fume
While I think this is neat, I doubt the added complexity of the device, extra space required for storage of charger and the chore of charging it are worth the benefit of a slightly better, easier slice. Might be nice for people with certain disabilities though.
pkulak
A lot of the cool stuff we have now started off for accessibility.
ChrisMarshallNY
Pretty kewl, but, for some reason, this old site comes to mind...
cush
If you have a sharp knife and a wet cloth under your cutting board chopping is a joy, otherwise it's a dangerous, tedious, and exhausting task that turns so many people away from cooking entirely
rcdemski
Why a wet cloth?
NortySpock
The wet cloth between the counter and the cutting block keeps the cutting block from sliding / moving on you when force is applied, which is more comfortable and safer.
haneefmubarak
I think the wet cloth is meant to increase friction between the surfaces
unwind
It stops the board from sliding.
kla-s
Stiction
Havoc
That looks really cool. Especially loved the wall of prototypes with raspberry picos etc.
Way outside the price range I'd consider personally but I look forward to having one in 5 years at a hopefully lower price point
Don't buy dumb electronic kitchen gadgets.
Get a good steel knife, learn how to sharpen it properly, and you're set for life.