Testing Strange Guillotine Blades (extreme results)

[@properprinting]

The shot starting at 15:32 hits me right in the feels. Wonderful ending to this epic adventure and I'm very happy that I was part of this. Thanks and well done!

[@KnowArt]

Yeah, crazy good times! Thank you too

[@paleintrovert6495]

I'm French and seeing the notification for this I instantly knew I was obligated to watch this

[@Solestial_dusk]

wild

[@joemcduck2748]

I’m sorry, I hope you get better (you are French) This is a joke By the way, love yourself!

[@crusader3108]

They need to do a "best strategy to invade another country" to bring out the British people

[@drewcagno]

Chad comment!

[@danser_theplayer01]

French and spaniards come in as close seconds in colonizing.​@@crusader3108

[@Coldmirror09]

I just love that you bought a guitar for the school and destroyed the old one. I like your way of thinking

[@KnowArt]

thanks :)

[@TheSupremeHaloMaster]

Same. I hate seing new, functioning things getting destroyed

[@waterslethe]

Agreed. I subscribed because of the classy touch.

[@AJR355]

The design is very human

[@KnowArt]

lol

[@foradecontexto4672]

very easy to use

[@Blaze6108]

Robespierre be like

[@DotasacWee2-tu4qk]

The result is usually something bad

[@johnbeauvais3159]

There’s a dark humor in how nothing you really tested beat what was already in use, while they couldn’t optimize the design using high speed cameras, there was no shortage of aristocrats to iterate the design on.

[@Runefrag]

Despite what so many people on the internet would have you believe, medieval humans were extremely clever and intelligent. They knew exactly what they were doing in most instances.

[@StarkRG]

@@Runefrag They weren't any stupider, they just had a smaller knowledge base to work with. We have a bigger one now, but most people don't bother using it.

[@PortRhouse]

Bambu Lab really out here sponsoring a video about the optimization of a guillotine. 👏 👏 👏

[@anchopanchorancho]

They want to be on the right side of history with this one.

[@benwaffleiron]

the bit at the end with the guitar is peak cinema to me. using it to play one last solo and then playing the recording over its own destruction. the little bow at the start. the respect you show for this hand-crafted object, even while destroying it for fun for a youtube video, is really nice to see

[@KnowArt]

:)

[@manpreet_singh_dhaliwal]

Imagine living in the olden days and coming home to say, "Honey, I got the tickets to the new public execution."

[@iarnaldo]

Yes, another billionair who wanted to scape from earth 😂

[@shayes.x]

As a musician and amateur classical guitarist myself, usually seeing instruments destroyed (even cheap or broke ones) is somewhat distressing, but I found it to be satisfying in this instance! I think in large because of the efforts you made to positively replace that guitar, and also because the guillotine cut was simply very nice compared to just smashing an instrument. EDIT: Also the fact that you honored the instrument with a final performance. Very cinematic and fitting!

[@Brainstormer_Industires]

Mad respect for deliberately finding a beat up, end of life guitar and donating the new one. Destroying things for clicks is truly a rot on society.

[@the__man]

ur a rot on society

[@VoIcanoman]

This feels very topical. Like knowledge that's going to be good to know in a few years. Would that more content creators gave us such a gift. Vive la révolution!

[@vlc-cosplayer]

"In a few years" 👀👀👀

[@supergiantbubbles]

Thumbs up for donating a new guitar to the school in exchange for their janky one you sacrificed. I'm really enjoying this series.

[@KnowArt]

thanks :)

[@frenchheavy4592]

The sharper bevel is probably performing worse on the meat because it pushes it less apart, causing the meat to stick to the blade more easily. Probably also the same reason why meat cleavers are thicker, a thin blade or highly sharp bevel angle would more likely result in sticking.

[@cavemann_]

An astute observation!

[@fermitupoupon1754]

With a single sided bevel you'd ideally be cutting with the bevel vertical and the flat side of the blade facing away from the sausage. As the cut is being made, the blade has to go in between the fixed sausage and the slice being cut. If the flat side of the blade is up against the immobile sausage it just gets pressed into that and the friction just builds up. If the flat side is against the slice being cut, it's much easier to push that out of the way and with only the bevel contacting the sausage friction can't build up as much. The reason why meat cleavers are thick, heavy blades is much more simple. The 30 degree bevel has more supporting material behind the edge, so it doesn't dull as easily as a sharper bevel. The mass is just there so the cleaver has more momentum to cut through bone easily. You don't use a meat cleaver to make precision cuts. As opposed to a filleting knife, which is flexible and has a very sharp bevel, because you don't want it to cut bone, but rather cut the meat off the bone. So it's light and thin for agility and precision.

[@KnowArt]

hmm.. I believe most of the meat cutting in a butcher shop is done with very thin blades and that the cleaver is there mostly for the bones, but I could be wrong! Interesting theory

[@frenchheavy4592]

@KnowArt It was just a quick thought that cleavers, being thicker and splitting the meat further out, would have less issue with sticking or friction. But, friction would probably be more an issue with thick slabs of meat. A thin slab is more about overcoming the initial resistance of the meat against cutting, where a sharper thinner knife would better suffice. Also yeah, I take back on friction being the reason for meat cleavers being thick. I can imagine it might be a small benefit though.

[@Salted_Fysh]

Not really relevant anymore but tatami mats are usually cut wet because a) it's a closer simulation and provides a more consistent cut and b) it doesn't run the risk of damaging the blade as much. Note that cutting a wet tatami mat cleanly is easier than cutting one dry because it doesn't dissipate the force in random directions as much.

[@Uncle_T]

Very much this.

[@danmur15]

15:10 i love this approach to sourcing props for a video, and it still produced great footage :D

[@KnowArt]

:)

[@kokilabendamor7615]

The French really liked this.

[@arenkai]

As a French, we are overdue an upgrade for future....... strikes.

[@toxicbavariankitten]

May I suggest: Rocket boosters (miniature ofc)

[@LifeInJambles]

Civil service is a thankless business. Best to invest a little time and energy into research and optimization beforehand to avoid troublesome hangi..... hangups.. down the road.

[@mr.sandman770]

Last time, I had recommended a curved blade like a saber or an axe, but I didn't take in to account something: an axe has a relatively short edge to focus its force in to a small area, and a saber draws across the target rather than push straight down. Thanks for trying it!

[@KnowArt]

My pleasure! :)

[@Duke7x]

The next anti-bourgeoisie revolution is gonna have the best guillotines 😂

[@jamesmorrison6204]

I swear everywhere I go I see their machines, Bambu Lab has really become popular recently

[@yungdung9835]

btw tatami mats are supposed to be wet beforehand to properly simulate human flesh, the dry tatami will have much more resistance than actual human flesh.

[@AdityaMehendale]

I was trying to cut "rubber tiles" last year - yes, the ones used in gyms and sport-halls. I used the ones from Hornbach, 50 mm thick, and had the unenviable task of making a tight seal around the rounded periphery of a rectangular trampoline. Tried various cutting-tools. The one that worked best was a bread-knife. But it was not about the knife. The least painful operation where I used my other hand to bend the "waste" rubber away from the piece I was trying to keep. The stretch made that the cut was helped along, and more importantly, that the two resulting pieces of rubber did not pinch the knife, in the form of a pair of excellent brake-shoes.

[@AdityaMehendale]

..what I'm saying is - any geometry that "spreads-apart" the separated pieces, with minimal surface contact area is likely to have the least energetic cut and/or least forceful cut.

[@BasicallyBaconSandvichIV]

Dat boek was zo zielig! Dat deed me bijna fysiek pijn gewoon! [That poor book! It nearly caused me physical pain!]

[@iopfarmer]

The 15° blade problem is not related to the sharpening or more cutting forces. I assume the left-hand sensors of the balance scale are more loaded than the right-hand ones because of the attack angle of the forces. The displayed load is wrongly calculated. The smaller the blade angle, the more you should see this effect, probably. The setup to remedy to that is not trivial...

[@KnowArt]

hm.. not sure about that. I tested the scale extensively with angled and off center loading and it seemed alright. But theoretically possible! thanks

[@sebbes333]

*@Know Art* 15:05 Very good 😃👍 Also, nice that you shared it's final tune with us :)

[@killzonearmed]

That camera joke was so funny LOL

[@uranium_beaver]

1) Considering how our civ is and how it develops such devices may see flamboyant comeback 2) Way you got guitar to the test is highly honourable and appreciated

[@MartynDerg]

I do really appreciate this video, and it's really humbling to know just how much people in the 1700s knew what they were doing. I hope this knowledge comes in handy to many people soon 👀

[@DapperDanLovesYou]

Loved that you swapped guitars, that's awesome!

[@getahanddown]

I agree with the friction. Try a groove behind the cutting surface to break the seal / let air in?

[@sebastiannielsen]

Here is why the 45 angle blade works the best: if you think of the forces involved. If you try cutting with a kitchen knife straight down on like a sausage or bread, it will cut poorly, but if you actually cut with the knife, ergo, move it sideways, it will cut much better. By angling the blade 45 degrees, you create the sideways blade motion that is needed to actually cut with the blade. If you would have a 45 degree rail instead, so the blade falls in a 45 degree angle, then the flat/straight blade would work better.

[@HipsterBaby747]

Max force is a good indicator maybe but what you really care about is the work, force integral over distance for the whole cut. Lower work means the blade is more efficient

[@HipsterBaby747]

The distance height is the energy available. Work is the change of energy. A blade requiring minimal work to cut will require minimal height

[@KnowArt]

well, all the footage is in the video, so you can work it out if you want...! I'd love to hear it

[@air8536]

Theory for why the hole blade was worse: the grooves continue all the way down the cutting edge where the most friction is compared to the hole which is just in the center

[@KptnAutismus]

we are gonna need this research soon 👀

[@slimjim2584]

I suggest wood glueing the guitar back together and restringing it to see what it sounds like

[@ReepsWasteOfTime]

I love Bambu. Obviously it’s their low end and is a sponsor so they are getting advertising but they did still send a printer and they are still somehow 2x better than anything at the price. I’m honestly amazed that since Bambo emerged there still haven’t been many or even any companies that have matched them.

[@ReepsWasteOfTime]

Wow you can change nozels without tools? That’s actually really cool! The P1S needs you to disassemble it, unplug a bunch of cables, remove like 10 screws and then put new thermal paste on. It wasn’t very easy… Their support also goes over the top with how much they do to help

[@richardgood7039]

In my understanding of cutting mechanics, a cut is only made when the blade slides lengthwise along it’s edge. A good example of this is the Mordhau, where you grab a sword by the blade and biff someone with the handle. This might explain why the 45 deg blade was best, as it’s profile ensures the leading edge always slides along the cross section of the ‘neck’, whereas the pointed/flat blades didn’t. Anyways, great vid! Look forward to seeing more from you

[@Hawk7886]

This is sweet! You booking appointments yet?

[@tsbrownie]

Think of the number of people who had to die to find the perfect cutting angle....

[@firefighter4443]

Excellent, relevant video for the times.

[@drecknathmagladery9118]

im not sure it is fair to do this at the small scale as it may not be visibly noticable to you or a camera but the way the guillotine works is that as it is falling on a rail it isnt going strait down regardless of how locked in it may be there is a slight wobble and there is play forward and backward in the blade itself you wouldnt get that with a 3d printer arm and infact despite the motions both being a simple up to down motion they actually use wildly diffrent mechanics the 3dprinter is infact using a cutting force relying on the sharpness of the blade where as the guillotine is actually more of a sheering/chopping force which relies heavily on the weight as well as the angle of the blades edge which is why im going to point out that the first blade on the big guillotine being hollowed out is actually holding it back.

[@ryansmiley5495]

I never thought about different blades. Awesome!

[@andiralosh2173]

Now if only we had proper use for guillotines...

[@kitame6991]

we do! we use modern mechanized guillotine to cut paper, sheet metal and PCBs.

[@andiralosh2173]

@kitame6991 I've used 'em! 😁 I was thinking this more traditional style tho

[@Derzuel]

The reason the blade with its center removed did worse than the blade with grooves carved into it is due to the blade having more give in the actual cutting edge resulting in needing more force to push the blade through. The blade with grooves carved into it still retained its structural integrity while the grooves themselves reduced over all surface contact thus reducing drag on the blade. This is in fact a phenomenon that is utilized in some high end kitchen knives, but usually more for keeping stuff from clinging to the blade than for making the knife cut better.

[@truist7]

Really excellent work on all parts of this investigation. Thank you!

[@KnowArt]

:)

[@Joseplh]

My theory on the pointed blade and why it failed as bad as it did is because the sausage held together with tension from both sides as the blade pushes it to the left and right. The 45-degree blade on the other hand avoids the tensile strength as it "peals" the sausage from one side to the other. The 45-degree angle also provides a cutting action compared to the flat blade, however it is a bell curve, because the greater the angle the more friction from the face of the blade is in contact as it makes a shallower cut.

[@lanchesternaanyane]

Bruh getting us ready for the day we eat the rich

[@tanmaysharma3135]

thanks for the information that helps me a lott :D

[@Rainyjax]

Microserrations are actually pretty easy to make! Anything from a scythe sharpening stone to a cheap grocery store grade knife sharpener will turn a perfectly smooth edge into a miniature saw. Especially the knife sharpeners that have rough stones instead of carbide inserts. Though I don't think they'd help all that much.

[@Maradnus]

I know from chefs knifes that the blade geomerty will make a a better knife even if it was sharpened by the same person & Jig same steel.. the blade geometry makes a differences depending on what you are cutting. this was very interesting to watch, many thanks

[@aoabali]

Some guy testing guillotine designs on the internets was what I needed to help me face the day.

[@here_be_dragons9184]

It's all about geometry. The more acute the angle, the better it should perform. It's just that at some point the blades become impractical and you probably don't want a too long travel time.

[@arcycatten]

Very nice that you gave them a new guitar to replace the one you would destroy!

[@putcandy0]

What about a potential 60° blade, making it even pointier? That could be better because it approximates a slicing motion more closely

[@grahamwaldo331]

Very useful information…..

[@evren.builds]

The sausage holder apparatus and 3d printer used to slice it is peak comedy for me. Stared at 7:44 laughing for a solid minute Please tell me you were eating the slices :D Next is actuation lengthwise to feed more sausage. Then we can have an on demand guillotine sausage server Ah probably should make that next time I'm in the workshop

[@riffzifnab9254]

You should give the remnants if the guitar back to the school as a reminder to the other instruments what the price of failure is. Also because the students who had to use that guitar would probably enjoy it. (:

[@giuseppebonatici7169]

you should seriously support the other side of the cut. that would reduce the cutting forces a lot, since the problem here is that the blade is plastically working the sausage before it breaks it, and it is expected to be a bigger problem as you go further, as the inertial momentum of the cross sections is getting worse (aka, more bending failure before shear failure = more energy wasted, more pressure required)

[@oscarguzman3017]

I like how he had the foresight to know people wouldn't be happy seeing a guitar used and found a clever solution that still allowed him to execute a guitar 😂

[@SloMoMonday]

I did not expect the energy of a Bond villain doing some casual rnd and its incredible to watch. I'm not too sure whats appetite for experimentation or the rules you follow, so if i could suggest somthing a bit crazy: a double blade system. For example you have a falling V blade thats weighted to effectively double its energy. And its attached via pully to a second reverse-V blade on an inverted system on the same track. The blades meet in the middle and you're effectively negating the rolling issue. Granted you are over engineering an ancient death machine and dangerously throwing a lot of kinetic energy at each other. But its in the name of progress.

[@bashibashi1]

Center cut line score 8.5!

[@freedomcaller]

In a 3D world, the edge of the blade is a rectangle not a line. Whatever shape works best on the main axis should also work best as the sharpening shape.

[@niepowiemjaksienazywam1972]

That feels like it’s a common misconception so I feel like I should correct you, more contact surface actually does not mean more friction. Only thing that matters is pressure, as the area the force is exerted on cancels out in the equation, you can find the information on how friction works in any high school physics textbook or probably any other book about dynamics.

[@thechumpsbeendumped.7797]

8:17 The briss-o-matic 3000.

[@5Demona5]

Quality content right here!!!

[@Uncle_T]

Great video, but I would love to see the same tests done with properly damp tatami mats the way they are prepared for tameshigiri and battogiri.

[@Saol.Alainn]

A few serrations along the upper few inches of the 45° blade might help catch those last few fibers 🤔

[@Fixti0n]

What i think is the reason as to why the hollow blade cuts worse then the grooved one is because of drag. Yes, a hollow room creates more drag then a grooved one because of how aerodynamics work. Long explanation short, big hole needs air to flow into the vacuum to fill the space, making it suck, while the grooves allow of a continuous flow that dont suck. Dumber explanation is how if you pour out a bottle, if you flip it over it pours slower and goes blub blub blub, but if you spin it first it flows fast and with no blub blub blub.

[@n_kliesow]

Just imagine how this device was optimized in the past. 😮

[@nikitalurye]

Having only seen you in shorts, it's really uncanny to not have goofy sound effects playing as you speak.

[@KnowArt]

hahaha

[@SpackJarrow94]

7:55 for instant ASMR

[@firebrandproductions6040]

id try an apple seed grind, like an axe, it works well for peeling material away.

[@635574]

After all that just slicing through the guitar was a big surprise

[@wsd5559_roblox]

Thanks for the knowledge!

[@SebastianD334]

I think the hole may have performed worse than the grooves due to a lack of strength, the blade may have been deformed and twisted instead of being as rigid as it still was with grooves. Also, I’m wondering whether a steeper blade would perform even better than the 45° blade. But if you do make a steeper blade, I’d recommend attaching more guiding wheels along it’s long side, as these would drastically reduce drag from pushing the wheels into the frame

[@yousfhelal321]

13:51 MY TOOOOOOOOOOOOE

[@Raciel1894]

I think the guys in the french revolution had enough "experimentation" to perfect the blades

[@Amybnuy]

getting ready for the state of the world I see.

[@StarkRG]

13:01 Ooh, that caravan is a lot like the caravan on the British Taskmaster, just full of random objects one might use for various tasks. Testing guillotines isn't a task I've seen them do yet.

[@jonathana.1802]

Guillotine perfect ornament for my appartement balcony. (It's a statement)

[@brown56765]

I wonder if the steeper bevel on the blade makes it easier by putting more tension on the cutting area

[@benholroyd5221]

Re hole v grooves. I wonder if you're weakening the blade and allowing it to flex? The only other thing is that the tatami beach mats can touch if there's a hole, that allows the 2 halves to bend towards each other, so rather than the tatami being split apart throughout the slice, the blade would behave the same as if it were starting slicing at the very beginning. My intuition tells me that this would help the blade slice, but given the results maybe my intuition is incorrect.

[@OddJobEntertainment]

I think there is a variable that's not accounted for that is causing some counterintuitive results. If we think of the cutting in terms of an x and y component, a more acute angle is producing less force to the x component and more of the force is going down. So the scale reading does not necessarily indicate a better blade. Constructing a rig to measure forces in x and z would be challenging but would provide a more accurate evaluation of the force magnitude. A test to determine if it was worth pursuin would be to check motor voltage and amperage (to check for strain) and possibly time required for the cut. I suspect you'll find variances here that indicate the scale doesn't tell the ehole story.

[@thomasclapham3360]

Could work better with a denser material? Tungsten maybe, perhaps glass for a sharper edge? 🤔

[@KnowArt]

hmm

[@anonym1984]

When the guitar came out, I kinda expected a cover of Rusty Cage's 'The Guillotine Song'

[@Duke7x]

Maybe you should rotate the brachistochrone 90 so it starts with the steep acceleration in the horizontal axis?

[@sammaxwell7051]

I a wasn’t French, but now I am!!! 🇫🇷 🇫🇷🇫🇷

[@principal_optimism]

Brachitochrone curve shaped blade would be my guess for the most effective

[@MegaJohny777]

If you are not in need of frequent sharpening, then you should have tested serrated/wavy blades that gives you a lot longer cutting edge and therefore a better result. Maybe.

[@bilbobeutlin3405]

Enough testing, when do you strap some french nobility into this beauty?

[@tiagotiagot]

What about two semi-circles, like a half-circle cut in half and with the halves swapped; kinda like "◞◟" or "ㅅ" (but with actual circle curvature instead of the variations the fonts may be introducing) ?

[@ehnehm]

How would a 60 degree blade work compared to a 45 degree blade? Is 45 degrees the optimal angle?

[@KnowArt]

I think steeper is better, but eventually it gets cumbersome

[@Scoopsdepoop]

Use electromagnets to PULL THE BLADE DOWN

[@Scoopsdepoop]

Or repel the blade up and through something.

[@AAO-Falcon]

rail-gun guillotine

[@ebiooo]

​@@AAO-Falcon railguillotine

[@Duolingo_on_meth]

Yum yum

[@mystifoxtech]

seems about right

[@Duolingo_on_meth]

@@mystifoxtech jam

[@Suger5zero]

I understand why intuitively. It might seem like the brachistochrome is the best shape But the blade is free falling at first and has plenty of time to accelerate regardless of the shape. And when the blade First contacts, it is not gaining an additional acceleration because of the shape of the blade. Also, the friction acts upon each part of the blade independently, regardless of how interacted with the other parts. That being said, I'm not convinced that mathematically. Speaking, the curve would give the blade an advantage in this particular case?

[@848]

Have you tested sharper angles? (50,55,60) If 30 deg is so much worse than 45, I wonder what would happen with sharper angles; does it get better, or is 45 the optimal

[@duytdl]

V shape blade should be made of two blades sharpened independently and stuck together (via welding or something)

[@alex.g7317]

What would’ve probably been better is if you just welded two sharpened triangles blades together for it to become the butterfly blade.

[@KnowArt]

! would've been an excellent idea

[@alex.g7317]

@ thank you!

[@Keldor314]

I'd worry about it being a potential fracture point. It's at the worst possible place for a weak spot. Actually, the butterfly shape in general would have this issue. Be careful with them, this sort of fracture could be dangerous.

[@alex.g7317]

@ to my neck or the blade?

[@Keldor314]

@alex.g7317 Dangerous to both. If we suppose that the blade breaks starting at the corner of the V shape, there's a lot of potential for flying fragments. While it's fairly unlikely that any such fragments will actually hit you, it is definitely possible to get unlucky and receive a serious injury or worse. Actually, thinking about it, welding together two pieces may actually be safer than using a single piece. Yes, the weld is a weak spot and the blade will be more likely to break, but when it does, chances are it will be a clean break along the weld, and you'll tend to be left with the two halves of the blade which, importantly, remain attached to their respective ends of the slide.

[@BrickGriff]

The brachistochrone blade seemed to push the bundle to roll a bit. Maybe it's not good for such a static situation?

[@user-uu9ru3de1y]

can you test my neck? :3c