As a frenchman, the biggest flaw in this experiment is that the mat is not fixed. In a guillotine the head would be enclosed in a wooden frame. When using the 45 degrees angle the mat is rotating loosing a lot of energy. If the mat was fixed it would have been cut much easily.
The biggest clue of why 45 degrees blade should work better is at 7:11 as the blade cutting the wood is moving sideways and not fixed. With a fixed blade it would require much more energy to cut through wood. With changing referential 45degrees blade is equivalent to the blade moving sideways therefore « slicing » instead of pushing through.
i was about to say the same thing, in the actual guillotine execution the neck is being held down by a wooden clamp to keep the body from moving, on their demo not only does the mat moves around the moment its cut the mat roll were also "loose". if its tied down for a more firm mat roll like the one they use in katana slicing, the cutting would me more efficient and consistent.
As a french person (never thought I would say that in such a context), it feels to me that having some sort of piece of wood with a hole in it to prevent the mat from moving sideways would eventually help the cut with angled blades. Also, you can make the carriage a bit "higher", ideally higher than it is large, measuring from most distant wheels contact points in each direction, this way it would be much less prone to rotation.
The biggest clue of why 45 degrees blade should work better is at 7:11 as the blade cutting the good is moving sideways and not fixed. With a fixed blade it would require much more energy to cut through wood. With changing referential 45degrees blade is equivalent to the blade moving sideways therefore « slicing » instead of pushing theough.
also, you could just have a bone through the mat for most accuracy. Though the spine is made of vertebre so maybe they intentionally hit the space between them.
You being French was completely irrelevant to what you said. It's odd that there are 2 French people here who both felt the need to say they're French even though it had absolutely no relation to what they posted. If I was French, I'd keep that fact to myself.
@@KamikazeCommie501 Saying I am French was a joke (even tho I'm French for real) regarding the history of France with the Guillotine --' I'm sorry if I offended you, that was not my intent...
As a Canadian I completely agree, but would generally substitute "higher" for "taller". There's also something strange about the direction it torques as it hits, they say it's because one side is heavier, but I think it's because one side hits first and slows down as the centre of mass tries to keep moving. The biggest thing is to spread the torque load over a longer range, but they may only need to do so on one side, perhaps by adding a well-braced wheel a few feet higher than the rest, on the side that hits last.
As an American I sincerely appreciate that you also included the measurements in bald eagles as well. Since metric is illegal here, we have no way of converting from litometers or deciwatts.
I researched a bit and found that "An angled blade ensures that the force is applied progressively from one side of the neck to the other, rather than all at once. This reduces the likelihood of the blade getting stuck or requiring multiple attempts, ensuring a more humane (relative to the method) execution." So the angled blade doesn't necessarily means its better at chopping, it could just make it more consistent/less likely to get stuck.
Yeah surface area is why it works much better. Causes more of a slice compared to a chop. Some say this is why the curve in some curved swords helps, but testing has shown conflicting data. Or that the curve would need to be ridiculous in order to matter. Personally I think curved swords are better slicers due to other factors like being single bladed which allows a thick spine to commit it's mass behind the edge. The curve helps with the mechanics of the swing at many angles, and edge alignment. But yet my favorite blades are still forward curved blades like a Kukri, some Yataghans, and Falxs! Gimme the choppah! My question is this considered a draw cut on a few of these? I also want to see a one sided uh 10 degree blade in action. About as verticle as you can go, while having the tip be made to miss.
thanks! I find that sentence not to contain very much information. Because... why? How exactly? Why is progressive cutting better than all at once? But thanks nonetheless!
@@KnowArt Imagine the flat blade cutting a cylinder with a 1m radius. If the blade moves 1m downwards after touching the cylinder, it will have already cut half of the cylinder. A 45º blade doing the same motion would only have sunk 1/sqrt(2) = 0,71m into the cylinder and thus require less effort. The total work needed to cut the cylinder should be about the same, but the angled blade puts the same amount of work on a longer period of time so it requires less force and cuts more smoothly. This should also be why the blades performed about the same in the guillotine, with a fixed amount of energy behind each blade. The difference should be exacerbated by instead measuring the amount of force required to start cutting into the material; the angled blade requires less force to start cutting, but the blade has to travel longer to complete the cut.
@@KnowArt If it helps, in the video you said that the blade does not see much use, however, during the French revolution it saw an unbelievable amount of use every day, so much so that by the end of the day it could take multiple attempts to cut a head clean off.
They're designed for cutting meat! There's a HUGE difference, it's way more stretchy and shock absorbant than wood or fruits. The flat blade would just bounce off someone's neck and potentially break it in the process. I'm surprised noone pointed out yet, you should try cutting actually meat or balistic jelly in the next video.
It is the material in the neck which is tough, ballistic jelly is more of the softer muscles and tissues. Most meat will not be this tougher neck cartilage/ligament/bone/muscle mix. Modern metal is also far less likely to break under such stresses, so it is doubtful they could test that out very well.
I watch many videos where historical and modern weapons are tested for effectiveness. I highly suggest you do at least one (they are $$$, unless you can get them to sponsor/ donate one) BallisticDummyLabs i believe is one of the companies that produce full sized, torso, skull, and other simulated anatomy. (Zombie ones are best because the blood is green and won't get you demonotized or at least make it less likely) This would be THE ULTIMATE way to see the effectiveness, as they use different materials to simulate organs and bones, Then you can use a reproduction of the head holder and it would be as close to historical accuracy as you can, Also maybe get the throw away scraps from a butcher and that way you can find a piece of meat as thick as the neck, with as close as you can find musculature, fat, bone, to a neck. Everyone who is saying cut meat (which shows they don't watch to the end), doesnt mention that the other parts like the ligaments/ muscle/ other structures. Check out Ballistic Highspeed, Garand Thumb, and many more channels to see Balllistic Dummies (I reccomend the Tank vs dummy, RPG vs dummy, shotgun, and rifle. The tank basically turns you to mist and chunks, the RPG Quarters and beheads you, the shotties will make at least half of a head dissapear and the slowmo of the wound channels is scary to see how our bodies would temporarily have large cavaties due to the speed of the penetration. Awesome video, I enjoy this kind of History meats science and engineering, and we see stuff get destroyed! Excited for round 2 a gel dummy torso with head would be so amazing
A couple questions for the OP. When the equipment was in regular use. One, Did they have the technology to know the difference and did they really care which one would be better? Back then, a blade was a blade. I'm sure they had some advances at the time. Did they have the ones YOU'RE talking about?
This for sure. The lack of tying down the mats (weren't people restrained and placed in those locks? Sure, mostly because people are gonna squirm when youre trying to kill them, but also to prevent the mats from rolling as 7kilos of razor sharp metal drops on them in freefall) kinda irked me, but the acknowledgment of flawed procedure and further testing is heartwarming - ironically, given the macabre subject. Always nice to see good science being done! Not that I expected perfection for such a laborious, expensive experiment to begin with. I wish I could test this sort of thing myself! (Another medieval device I wish I could build/test irl: Trebuchets/Mangonels.)
Another possibility you could test is an inverted version of the point where they move inwards towards a point kind of like an "^" shape instead of a "v" shape
Former machinist and manufacturing engineer. There's a lot of cutting physics at play here - one of the biggest ones that I'd immediately fix if this were a machine I was working on is the carriage rails. A good rule of thumb is you want the length of the bearing surface a least phi - golden ratio - times longer than your maximum span. This provides the counter-moment to keep the crossbar from twisting. If you are expecting huge forces, you want the cutting point as close to the rear of the bearing surface as possible - this forces the carriage to align with the cutting force for the same reason boats float. Second, the anvil is important. If you want the absolute maximum performance out of a chisel-style blade, you have to imagine it like a pair of scissors. The bottom shear also needs to be sharp, even if it's 90 degrees. The blade should smoothly engage with the anvil before it makes contact with the material; this is why big industrial shears are shaped like scissors. It keeps the shears in contact with each other so they can't cut into one another. Important to this, the shear gap - clearance between the blade and the anvil - is critical. Too small of a gap dramatically decreases cutting performance, as the viscosity of whatever's getting dragged into the gap provides more friction than the cut force. Wax handles this really well, because what you're actually doing in a wet situation like this is forming a hydrodynamic bearing between two hydrophobic steel surfaces. With wax, you can just spray water and it will perform as a lubricant.
Some things to consider: - angling blade gives it more surface area, is there a reason that's needed? - the angle might be for other factors than cutting efficiency or sharpness - necks are squishier with a bone core (does angle improve getting through that specific material? Would the neck 'jiggle' too much if the blade was flat? Was it for a much cleaner cut for 'presentation' after?) - necks are messier (does the angle control mess?) - shape could be legacy from other methods (ax shape?) - shape could be legacy from a tool (" we need this thing, take that peasant tool that cuts really well and make it bigger!" - maybe like a scythe) - it could be that historical guillotine blades worked so well for their given task that no one really took the time to make it more efficient
thanks! great list. Didn't consider that there might be a reason other than pure cutting efficacy. The best source we have about the origin of the angled shape is the great grandson of the maker of the first guillotine. In his story he tells that the king of france (who was fat) told the maker that the flat blade that was on the first drawing wouldn't work for big necks. The maker looked at the king's neck and agreed. The king then suggested an angled blade, and was ironically beheaded a couple years later, in the french revolution. But the story doesn't tell anything about the true reason why it would be better, but it implies that it's not a leftover from axe designs or anything like that.
@@KnowArt it likely comes down to the physics of slicing rather than pure efficiency (what you're testing for). Any angle will increase cutting force required (45 degrees just being (blade width / sin(45)), so 41% more force required). But when it comes to hard materials that you want to slice rather than crack, as with your car/mountain example, the cutting efficiency is higher at an angle because the relative blade angle is finer, allowing for the cut to go deeper into the substance before the spine (of the blade) is engaged and cracking / wedging is the only force involved in the splitting. It's odd to say that something takes more force but is more efficient, but that simple math doesn't take into account the mush easier time an angled blade has at initiating the cut (usual range is 25-50% better), but I can't do that math without the specifics of both the material and blade geometry. One of the main issues with your set up is the use of the mats, they're woven, and loose. A flat blade should behave the best in this scenario as it can compress the mat into a stationary mass, plus interlocked fibers tend to resist slicing. It's the same reason that a flat blade will have an easier time going through woven kevlar than a slicing blade.
@@AaravNarayan-s9x Do you know of better ways of spending your time than improving of an already great design? The other day I was reading about wealth inequality. My brain took me automatically to the wiki page about the machine monsieur Guillotine popularized. Now YT is offering videos of these guys. I consider my journey a time well spent!
a lot of people with a lot of suggestions, but honestly your methodology was fine your equipment was just malfunctioning. The bearing assemblies are good, they just need to be longer. They can't resist the turning torque because they are too close to the source and don't have enough leverage. Making the carriage longer, and putting additional rollers on the end, would provide higher resistance but would give far better mechanical advantage to resist the cutting induced torque. An example would be something like a shaper, which has a very long rail compared to its cut/stroke depth, often less than half. This is because all the extra interface between the carriage and the rails allow for far higher rigidity, far better predictability, and less deflection at the cutting edge. OH and try to constrain the mats, and dont forget to soak them in water. IIRC the tatami mats are supposed to be soaking wet for cutting, although that may be lies fed to me by internet strangers.
I also thought that the wheels might be too close together, spreading them out might be a good idea. Looking up some guillotine images, the rail system seemed to have longer spread as well, for most of them at least.
@@LouisEmery tbh I just look like him and thought it was funny, although a lot of people have a lot of either very awful things to say or very interesting things to say. Your comment was definitely of the interesting variety lol
I think the problem with that idea is they're not using it at it's max velocity/height. At a higher velocity, it has a lot more energy and much less time to rotate.
As I remember they had to throw buckets of water on the blade at one point to keep it from warping. But as I understand it, at the height of the Revolution, sharpness was not a consideration. Maybe in the original design, but not as a matter of practicality.
#1 no head hole, a real guillotine has a board with a hole that prevents the neck from moving to the side. Without it the cut object moves away both losing energy and eliminating the slicing effect from the blade being angled #2 bracing the rails in a few places to make them wobble less. You can see the wheels losing contact, this lets the blade come in at an awkward angle and makes it easier to hit the wood. #3 using a very thick sausage with a skin like a giant salami/mortadella would be a good idea because its internal structure does not slide about so much and it has a skin. Maybe even wrap it in pig skin for better effect. Having to cut the skin does make it more difficult and an exceptionally bad blade design would be more likely to achieve crushing damage instead of a cut, because it will mash all the interior but won't go through the skin. There are about neck-thick mortadellas and salamis but they are expensive.
The catchment at the bottom that the blade slots into doesn't need to be very close together. You can easily fix some of the wood-hitting just by moving those further apart. (Though, that may mean making the carriage a bit thicker). Can't wait for round 2!
This is what I suspect as well. Anything that minimizes the blade rotation should limit travel friction, and even a small increase in friction can make exponential differences in the results as it deflects energy sideways over the full length of the cut. This would go a long way toward explaining the similar results between the traditional and flat blades, as the flat one is better balanced.
@@faceoctopus4571 No they mean because it's a long strip mounted at an angle, it's the same width all the way across. The angled blades in the video have more material on one side than the other.
I am not sure that the weight distribution matters, if anything, it should be an advantage. During the fall, it is essentially a free fall, especially with modern bearings, so no significant torque would be applied. However, once it hits, the thick, heavy, part will hit first, limiting initial rotation because the center of gravity will be closer to where the force is applied, limiting torque.
You may take note that the (potentially used) guillotine blade is much wider, and it's carriage was probably not a set of complex rollers and what looks like 3D printed plastic, but a frame or two pieces of wood fitted to the ways of the frame. Yes, this will result in more friction losses than rollers, but it would also make it impossible for the blade to significantly turn aside from the cut. You can torch blacken and then sand and polish the frame to make it's surface a bit smoother and harder than the sliding blocks which will help to prevent binding and friction. *Edit, the tatami mats you were using are best at simulating flesh when they've been left to soak in water for some time, tie the ends of your test piece together tightly with chord and soak the whole thing in water for a good amount of time before cutting it. This will make it expand and build some tension in the fibers which will make it as flesh-like as a mat of plant fiber can be.
The Brachistochrone curve should be pointed in the middle with curves going outward from the middle on each side just like the pointy blade. That would make more sense since usually the object being cut doesn’t start from one side but rather from the middle.
We love your videos and thanks to the lack of loud and annoying music and soundeffects my partner loved it too. thanks to you i was able to share a common interest that's otherwise often lost to too much noise. so thank you for investing time and effort in presentation and research rather than effect and editing.
I like how you do ad reads, it surpasses the rest by making full use of your screen rather than stopping the whole video for said read. You also use sponsors as comedic relief using adam and ev- ahem, i mean through ingenuity
I appreciate the fact that you actually read everyone's comments and noted their suggestions. Most youtubers with a channel of your size do not go through that effort.
The tatami you are using are indeed used for katana testing, but please be mindful that they need to be wet (not soaking, but moist) to properly be used.
as long as they are consistent between tests it's all good for us, I believe. I didn't want them to dry out throughout the day, so I kept them dry to begin with
@@KnowArt ah. that makes sense, but I belive the standard method is to just keep them in a bucket or something when you're cutting others- they don't work as well if you don't soak them you also want to roll them farily tightly- I think?
They are meant to be soaked overnight and then be left to dry to not be soaking wet afterwards. Even with your consideration the result may vary drastically. Imagine trying to chop a piece of firewood with a 10% moisture total or one with 60%. That is quite the difference.
@@cal593 1000 kilogram is when you have 264.172 gallons of water, cuz 1L is 1000 grams which equals 1 kilogram and 1000L is 1000 kilgram or 1 metric ton. Also 1111 1/9 9mm bullets next to each other equal 1m in length, 1 cubic meter so 1111 1/9 9mm bullets in Y, X and Z axis equals 1000L of volume.
The guillotine you showed from the museum, was of equal width, not having the issue, of imbalanced weights, while in your prototype you use an entire right-angle triangle,e which makes it bend, so yeah try the. one similar to the museum for better accuracy, great work btw.
Thank you for this excellent video! For part two, I'd recommend using pipes and grooved pipe wheels (possible on both sides) to improve carriage stability and having some sort of brace for the target to avoid slippage/rotation (this shouldn't be a huge issue, but it's still a variable that shouldn't be ignored). Anyway, I can't wait for part 2!
As a future guillotine builder I appreciate all of the work you have done. You have illuminated a bunch of engineering considerations I'll have to keep in mind in the future.
One flaw is the Mass is not fixed, so the potential energy is higher and also it's inertia. Also I think the original is angled because it allows one side of the blade to slot in between the wood thus aligning it to not hit the wood.
Mass is constant, all blades are exactly 10 kg. Proper Printing emphasized on this and showed how they added ballast to bring mass deviation to under 100 grams.
@@JosGeerink Any blade shape can be slotted into tracks along the edges, the thing with the slanted blade is that leading edge is the part closest to the track, thus the part subject to the least wiggle.
First watch of your lecture and I am in. I really like how you bring the assumption of some technical knowledge but still use real examples. Thank you kindly for sharing.
While the Imperial Bald Eagle is still the most common unit of weight and mass in most of the US, in industry, we've been using decimal B.E. since WWII. Not quite as modern as the Dutch Decimal Lion, but it gets the job done.
Wait a minute. All the years I have been clueless about compressing the material and cutting from the "easy" side. Thank you!! I will take this to the test when I cut that giant bush in front of our house this fall And hopefully the shears won't randomly get stuck anymore.
You forgot a shape. The inverted pointy. Like an open pair of scissors getting slammed down that will focus the cutting power inward towards the middle.
And in the middle it'll crush I guess. The pointy forces outward forcing cracks or cutting, inward makes it crack or crush. Let's say it makes the target material denser and denser stuff is harder to cut
“Not used all day every day.” Many Frenchmen would say otherwise in times past. Prediction - the highly concave curve will progressively increase resistance, as the top is practically flat. Necks were restrained too. Great video! 👍🏻
5:30 I think this example is somewhat faulty. When you cut a cucumber, or most other foods; with a knife, you don’t tend to bring the whole blade down at once. You place the tip of the knife on the cutting board and chop it down onto the food. In such a case only some of the knife interacts with a small section of the food at once and moves across from there, which I think is similar to the effect of an angled blade.
As someone who has built industrial guillotines, I can tell you, you need to make the carriage taller than it is wide (2 to 1) and you need a tighter fit between the carriage and the guide rails. I had to do some experimenting when I designed my guillotines, and found that a 5 to 6 degree angle on the blade with a 15 degree bevel worked best for cutting through the material I was working with - polyethylene plastic. Obviously, the blade needs to be designed for the material your cutting through.
@@ral008 Yes, I'm a 368 years old Parisian😜. But, seriously, the style of cutters I have designed and built are generally referred to as guillotines, in industrial applications, because the blade moves vertically in some sort of guide; however, rather than gravity power, they use pneumatic or hydraulic power. I even built one that cuts in both directions - up and down.
i think you should have fixed the mats, like the heads didnt have space to move as well during those times so it may change things if you didnt allow the mats to move
People already addressed your apparatus problems, and much better than I could. I think you should also add a convex brachistochrone blade. Most weapon blades (and modern tools) designed for slicing used convex cutting edges
I absolutely enjoyed the video and look forward to part two. I have a few things to say about methodology: - the mats are meant to be watered. - there are devices to measure sharpness (e.g. bess). Would be great to verify the blades are similar in sharpness. - fixing the mats in place would prevent many factors of interference. Also it would be more accurate.
When I worked for a commercial press (printing company), they used modern guillotines, which uses a hydraulic piston to press the knife's blade through the substrate quickly, and then then raise it back up again, ready for the next cut.
There is a couple of things that I can add that, while not necessarily helping or hindering your results, will provide extra consistency to the results. First, tatami mats, when used as a cut testing medium are supposed to be soaked in water. This will soften and tighten the fibers as well as making them much less likely to just break when pressure is applied. Second, the mats need to be bundled tightly and bound so that they don't unroll or unravel under the pressure of the blade landing on them. Unbound and loose as you had them here, the spread of the mass of the tatami could move around making some portions of it easier to cut, and being that they were dry, it made the whole thing easier to just break rather can be cut properly. It may only provide a minor difference, but in science, consistency is important! Hope this helps.
Interesting video! The main difference I can see between your angled blades and the historical one is that due to its geometry, the historical blade was fixed to the frame near the edge on both sides, which prevents the blade from rotating on impact. I think if you try attaching the blade to the frame near the bottom of the blade on both sides, the angled blades will perform better.
if there's too much weight on one side with angled blades, the fix is simple. add enough weight to the light side balance it out. This will keep the blade straight at least until impact. To avoid the blade tilting on impact, you could add even more weight to the light side, but then the blade would tilt in the opposite direction during the fall. You partially did this when you added a piece of wood to the flat blade to compensate for weight difference, but instead you'd have to account for how much extra weight is on the heavy side, to add it back to the lighter side. If all blades are to be the same weight, then you'd have to recalculate how to cut the blades, so that you can add the extra weight after you have the blade shape.
If you're looking to test edge shapes and angles specifically, I'd build the frame out of steel instead and increase the length of the carriage to provide better resistance to the blade trying to rotate. Wood can get pretty flexy, and your blade trying to rotate will try to push the rails apart. The more the rails flex outwards, the more misalignment can happen, further exacerbating the initial clearance issues, causing the carriage to wedge itself against the rails harder. A solid set of rails and a carriage with bearings spaced farther apart will help minimize the losses of the carriage wiggling around and trying to press itself into the rails with the uneven loading caused by an angled blade. As others have said, constraining the mats could also help prevent some losses due to shifting, as could tying the mats tighter to prevent whatever shifting you can. Pretty easy to accomplish both by just clamping em in place a couple inches from where the blade strikes. Not sure if the blade wedging the carrier against the rails or the mats shifting out of place is causing more losses, but pretty sure that each of them is doing their part. The v-shaped blade certainly helps both of those though, which I imagine is part of why it did so well.
This is what cracks me up... This gentleman is expolating fact with suggestions for improvement... Along comes all the internet's self proclaimed authorities on the subject.😆
Looking at your slow-mo footage , I have a few suggestions . First , roll your mats tightly . If you compare your mat footage to the meat you cut , you'll notice that the meat has very little give . The mat x on the other hand , is absorbing a lot of the impact before giving the blade a more solid surface to cut through . Second , if you look at traditional guillotine designs , there is either a hinged stock with a hole for the condemned person to out their head through , or at the very least a rounded trough for their neck to sit in . Both items do the same thing , keep the neck stable and secured as the blade passes through . Watching your footage , your mats tend to roll for every blade but the flat or double bevel as the force is focused straight down on those 2 designs . Third , I'd design your blade carriers so that they push into the uprights slightly to alleviate the side loading issues you had . You might try making them longer so that whatever sideways force is applied is spread over a much longer area .
Interesting exercise. If you're only interested in blade design, I suggest a VERY robust, rigid, low-friction, metal frame with a lubricated metal slot in which the blade travels. Use a long, symmetric blade frame designed to minimize blade rotation for asymmetric blades. And a semicircular well or adjustable side constraints for the mat bundle to prevent lateral movement of the target. Also make the blade slot under the target wide enough that the blade NEVER contacts it. If you want to get geeky, interface a 1000g accelerometer to an Arduino and read it at about 10kHz.
Would it not be better to have a straight channel groove cut into either side of the tower beams that guide the blade the entire time, and doesn’t allow the blade to rock left or right like your rollers are allowing it to do? I understand that the rollers reduce friction, but you are also allowing for a lot of extra movement in the blade. Giving the blade a dedicated channel to follow would prevent the blade from deflecting off of the material that you are cutting. And as I see others have mentioned, fixing the material in place would prevent uneven cutting. And lastly, I know it’s expensive, but ballistics gel would give you a more consistent result, rather than the matting. Eliminate all of those unnecessary variables, and I think you’ll find the slicing motion of the angles blades would be more effective than a flat blade. Though, I do think you’re onto something with the brachistochrone blade. Im interested to see what changes you make in the future, just subscribed. 🤙🏻 Edit: thinking about it a few minute later, it would be easier to just install two pieces of angle iron on either tower beam, to create the channel. Rather than cutting grooves in the wood. Space the angle iron a few mm larger than your blade thickness and you’re in business. Far less deflection of the blade, and you won’t miss your slot in the bottom.
I would like to applaud you for how you presented your sponsor segment. Usually I just skip that part of any video, but by having a VO and actually interesting footage I watched the whole thing. Good Idea and I wish more people did that.
I was about to come into the comments and say something along the lines of "as per the cutting theory explanation you provided earlier in the video about how slicing with a horizontal motion creates tension in the material which makes it easier to cut, a reason why the angled blades didn't perform as well as expected is (I assume) probably because the mats were rotating as they were being sliced, reducing a lot of the tension from the mat as it's being cut, whereas someone's head is fixed in place in a guillotine where it cannot move like that, therefore tension is maintained throughout the entire cut," but then I see that many people have already said something similar haha
Another thing to keep in mind(at least with using tatami) is that the mats are meant to be soaked in water overnight in order to provide a more accurate simulation of a human neck/limb.
5:25 This is a really good point and it took me a minute to realize the alternate explanation. Sliding a blade along a surface to cut it in a slice is different than a chop. The 45 degree angle more closely approximates slashing a long blade across the target, rather than whacking it like an axe.
if you're a carpenter you already know what the difference is. if you're working with a plane, you can use something we call a "pulling cut" (literal translation from geman), which is angling the plane so that the blade makes a slight sideways motion in addition to the forward motion. it makes it easier. working with a plane is hard work!
As an ex cook I can tell you that the problem is the bone. Normally with a flat cut you can fail to make a clean cut, it has to broke it in only one opportunity. The angled shape make's a cut from the side (with the flat one you make a cut with 5 cm of the blade, in 45° you make a cut with something like 7 cm). If you try the pointy blade in bones you have a high risk to break the blade. The bone is the secret, you can ask to any japanse swordman why katanas got that shape. The idea is to avoid to get stuck on the bone (and if it does, it make's it easy to remove). The other thing is the only one sharp side blade, it's used to make the blade thinner and avoid the cutted element to get glued to the blade. It's used in many japanese professional knives. Your video is really interesting.
Suggestions: 1. Make something that holds the thing in place so it can't move as it's being cut. 2. Make a bigger hole for the blade to go through so it doesn't hit the wood. 3. Make the blade wobble less, this can be done by increasing the length of the gantry.
Don't forget that when those Old Dewds would cut your neck off, you'd put your neck in a rounded trough, and a matching piece would slide down on top to act as a collar, fixing your neck in place with little room for movement. That would 1) keep your neck from rolling/twisting as any slanted blade would apply torque, and 2) keep your neck from sliding away laterally as well. The mats in the test were free to turn and be pushed aside, which is probably what screwed with the readings. Even fixed pegs on either side holding the mats in place would help prevent that.
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Why does it say 2 days ago, if the video was 5 mins ago for me
Ah yes, the morbid interest. Alpha and Omega of any scientist.
@@INTERCOM8042 it was available to patrons already while we got the last things in place to actually publish
heh no other sponsor now?
Thank you for the freedom units. 🦅🇺🇸
As a frenchman, the biggest flaw in this experiment is that the mat is not fixed. In a guillotine the head would be enclosed in a wooden frame. When using the 45 degrees angle the mat is rotating loosing a lot of energy. If the mat was fixed it would have been cut much easily.
The biggest clue of why 45 degrees blade should work better is at 7:11 as the blade cutting the wood is moving sideways and not fixed. With a fixed blade it would require much more energy to cut through wood. With changing referential 45degrees blade is equivalent to the blade moving sideways therefore « slicing » instead of pushing through.
Was my immediate thought.
Gotta make sure that rolling doesn't occur.
i was about to say the same thing, in the actual guillotine execution the neck is being held down by a wooden clamp to keep the body from moving, on their demo not only does the mat moves around the moment its cut the mat roll were also "loose".
if its tied down for a more firm mat roll like the one they use in katana slicing, the cutting would me more efficient and consistent.
thanks! Will probably try that next time
I love how being french is a position of expertise in the matter, even though the method stopped being used for several decades now 😂
i really like the calm nature of this video, no shouting, no weird sound effects, no video effects, just knowledge.
thanks, great to hear
And no annoying music!
Ironically, all of these features are present in Proper Printing's video, and I like that.
Agreed!
You can see and hear when it's not done by americans.
As a french person (never thought I would say that in such a context), it feels to me that having some sort of piece of wood with a hole in it to prevent the mat from moving sideways would eventually help the cut with angled blades. Also, you can make the carriage a bit "higher", ideally higher than it is large, measuring from most distant wheels contact points in each direction, this way it would be much less prone to rotation.
The biggest clue of why 45 degrees blade should work better is at 7:11 as the blade cutting the good is moving sideways and not fixed. With a fixed blade it would require much more energy to cut through wood. With changing referential 45degrees blade is equivalent to the blade moving sideways therefore « slicing » instead of pushing theough.
also, you could just have a bone through the mat for most accuracy. Though the spine is made of vertebre so maybe they intentionally hit the space between them.
You being French was completely irrelevant to what you said. It's odd that there are 2 French people here who both felt the need to say they're French even though it had absolutely no relation to what they posted. If I was French, I'd keep that fact to myself.
@@KamikazeCommie501 Saying I am French was a joke (even tho I'm French for real) regarding the history of France with the Guillotine --'
I'm sorry if I offended you, that was not my intent...
As a Canadian I completely agree, but would generally substitute "higher" for "taller".
There's also something strange about the direction it torques as it hits, they say it's because one side is heavier, but I think it's because one side hits first and slows down as the centre of mass tries to keep moving. The biggest thing is to spread the torque load over a longer range, but they may only need to do so on one side, perhaps by adding a well-braced wheel a few feet higher than the rest, on the side that hits last.
As an American I sincerely appreciate that you also included the measurements in bald eagles as well. Since metric is illegal here, we have no way of converting from litometers or deciwatts.
well... y'all use grams and millimetre as well... just for the wrong reason, apart fro NASA they cool
I researched a bit and found that "An angled blade ensures that the force is applied progressively from one side of the neck to the other, rather than all at once. This reduces the likelihood of the blade getting stuck or requiring multiple attempts, ensuring a more humane (relative to the method) execution." So the angled blade doesn't necessarily means its better at chopping, it could just make it more consistent/less likely to get stuck.
Yeah surface area is why it works much better. Causes more of a slice compared to a chop.
Some say this is why the curve in some curved swords helps, but testing has shown conflicting data. Or that the curve would need to be ridiculous in order to matter.
Personally I think curved swords are better slicers due to other factors like being single bladed which allows a thick spine to commit it's mass behind the edge. The curve helps with the mechanics of the swing at many angles, and edge alignment.
But yet my favorite blades are still forward curved blades like a Kukri, some Yataghans, and Falxs! Gimme the choppah!
My question is this considered a draw cut on a few of these?
I also want to see a one sided uh 10 degree blade in action. About as verticle as you can go, while having the tip be made to miss.
Wich is why it was invented in the first place
thanks! I find that sentence not to contain very much information. Because... why? How exactly? Why is progressive cutting better than all at once? But thanks nonetheless!
@@KnowArt Imagine the flat blade cutting a cylinder with a 1m radius. If the blade moves 1m downwards after touching the cylinder, it will have already cut half of the cylinder. A 45º blade doing the same motion would only have sunk 1/sqrt(2) = 0,71m into the cylinder and thus require less effort.
The total work needed to cut the cylinder should be about the same, but the angled blade puts the same amount of work on a longer period of time so it requires less force and cuts more smoothly.
This should also be why the blades performed about the same in the guillotine, with a fixed amount of energy behind each blade. The difference should be exacerbated by instead measuring the amount of force required to start cutting into the material; the angled blade requires less force to start cutting, but the blade has to travel longer to complete the cut.
@@KnowArt If it helps, in the video you said that the blade does not see much use, however, during the French revolution it saw an unbelievable amount of use every day, so much so that by the end of the day it could take multiple attempts to cut a head clean off.
They're designed for cutting meat! There's a HUGE difference, it's way more stretchy and shock absorbant than wood or fruits. The flat blade would just bounce off someone's neck and potentially break it in the process. I'm surprised noone pointed out yet, you should try cutting actually meat or balistic jelly in the next video.
at the end of the video you can see us cut some meat! We cut even more off camera. It didn't seem very different tbh, but might try
It is the material in the neck which is tough, ballistic jelly is more of the softer muscles and tissues. Most meat will not be this tougher neck cartilage/ligament/bone/muscle mix. Modern metal is also far less likely to break under such stresses, so it is doubtful they could test that out very well.
I watch many videos where historical and modern weapons are tested for effectiveness.
I highly suggest you do at least one (they are $$$, unless you can get them to sponsor/ donate one) BallisticDummyLabs i believe is one of the companies that produce full sized, torso, skull, and other simulated anatomy. (Zombie ones are best because the blood is green and won't get you demonotized or at least make it less likely)
This would be THE ULTIMATE way to see the effectiveness, as they use different materials to simulate organs and bones,
Then you can use a reproduction of the head holder and it would be as close to historical accuracy as you can,
Also maybe get the throw away scraps from a butcher and that way you can find a piece of meat as thick as the neck, with as close as you can find musculature, fat, bone, to a neck.
Everyone who is saying cut meat (which shows they don't watch to the end), doesnt mention that the other parts like the ligaments/ muscle/ other structures.
Check out Ballistic Highspeed, Garand Thumb, and many more channels to see Balllistic Dummies (I reccomend the Tank vs dummy, RPG vs dummy, shotgun, and rifle.
The tank basically turns you to mist and chunks, the RPG Quarters and beheads you, the shotties will make at least half of a head dissapear and the slowmo of the wound channels is scary to see how our bodies would temporarily have large cavaties due to the speed of the penetration.
Awesome video, I enjoy this kind of History meats science and engineering, and we see stuff get destroyed! Excited for round 2
a gel dummy torso with head would be so amazing
@@robford4679 “is this getting weird for anyone else?” -Dan Olson
A couple questions for the OP.
When the equipment was in regular use. One, Did they have the technology to know the difference and did they really care which one would be better?
Back then, a blade was a blade. I'm sure they had some advances at the time.
Did they have the ones YOU'RE talking about?
Ah, the fresh lemonade stand. Very good.
haha
Yes, with said lemons being stored in a rusty cage
I love lemonade. Truly a revolutionary drink.
Happy Tree Friends reference? This was one of the first episode i watched.....🫠
@@metalema6 Heh. Cultured.
Honestly I really respect that you admit the faults of the testing methodology and are willing to try again
thanks! that's lovely to hear
This for sure. The lack of tying down the mats (weren't people restrained and placed in those locks? Sure, mostly because people are gonna squirm when youre trying to kill them, but also to prevent the mats from rolling as 7kilos of razor sharp metal drops on them in freefall) kinda irked me, but the acknowledgment of flawed procedure and further testing is heartwarming - ironically, given the macabre subject.
Always nice to see good science being done! Not that I expected perfection for such a laborious, expensive experiment to begin with. I wish I could test this sort of thing myself! (Another medieval device I wish I could build/test irl: Trebuchets/Mangonels.)
Another possibility you could test is an inverted version of the point where they move inwards towards a point kind of like an "^" shape instead of a "v" shape
could be fun!
Yes. I was thinking of a C shape. Like a sickle.
Although that shape would be significantly more difficult to sharpen
let what's tried and true slip through
Smart although that seems a like a pain in the butt to sharpen.
Former machinist and manufacturing engineer. There's a lot of cutting physics at play here - one of the biggest ones that I'd immediately fix if this were a machine I was working on is the carriage rails. A good rule of thumb is you want the length of the bearing surface a least phi - golden ratio - times longer than your maximum span. This provides the counter-moment to keep the crossbar from twisting. If you are expecting huge forces, you want the cutting point as close to the rear of the bearing surface as possible - this forces the carriage to align with the cutting force for the same reason boats float.
Second, the anvil is important. If you want the absolute maximum performance out of a chisel-style blade, you have to imagine it like a pair of scissors. The bottom shear also needs to be sharp, even if it's 90 degrees. The blade should smoothly engage with the anvil before it makes contact with the material; this is why big industrial shears are shaped like scissors. It keeps the shears in contact with each other so they can't cut into one another. Important to this, the shear gap - clearance between the blade and the anvil - is critical. Too small of a gap dramatically decreases cutting performance, as the viscosity of whatever's getting dragged into the gap provides more friction than the cut force. Wax handles this really well, because what you're actually doing in a wet situation like this is forming a hydrodynamic bearing between two hydrophobic steel surfaces. With wax, you can just spray water and it will perform as a lubricant.
oh thanks! interesting fact about the small gap! very cool
Some things to consider:
- angling blade gives it more surface area, is there a reason that's needed?
- the angle might be for other factors than cutting efficiency or sharpness
- necks are squishier with a bone core (does angle improve getting through that specific material? Would the neck 'jiggle' too much if the blade was flat? Was it for a much cleaner cut for 'presentation' after?)
- necks are messier (does the angle control mess?)
- shape could be legacy from other methods (ax shape?)
- shape could be legacy from a tool (" we need this thing, take that peasant tool that cuts really well and make it bigger!" - maybe like a scythe)
- it could be that historical guillotine blades worked so well for their given task that no one really took the time to make it more efficient
thanks! great list. Didn't consider that there might be a reason other than pure cutting efficacy. The best source we have about the origin of the angled shape is the great grandson of the maker of the first guillotine. In his story he tells that the king of france (who was fat) told the maker that the flat blade that was on the first drawing wouldn't work for big necks. The maker looked at the king's neck and agreed. The king then suggested an angled blade, and was ironically beheaded a couple years later, in the french revolution. But the story doesn't tell anything about the true reason why it would be better, but it implies that it's not a leftover from axe designs or anything like that.
@@KnowArt it likely comes down to the physics of slicing rather than pure efficiency (what you're testing for). Any angle will increase cutting force required (45 degrees just being (blade width / sin(45)), so 41% more force required). But when it comes to hard materials that you want to slice rather than crack, as with your car/mountain example, the cutting efficiency is higher at an angle because the relative blade angle is finer, allowing for the cut to go deeper into the substance before the spine (of the blade) is engaged and cracking / wedging is the only force involved in the splitting. It's odd to say that something takes more force but is more efficient, but that simple math doesn't take into account the mush easier time an angled blade has at initiating the cut (usual range is 25-50% better), but I can't do that math without the specifics of both the material and blade geometry.
One of the main issues with your set up is the use of the mats, they're woven, and loose. A flat blade should behave the best in this scenario as it can compress the mat into a stationary mass, plus interlocked fibers tend to resist slicing. It's the same reason that a flat blade will have an easier time going through woven kevlar than a slicing blade.
Do all of you have like infinite free time??
@@AaravNarayan-s9x Do you know of better ways of spending your time than improving of an already great design? The other day I was reading about wealth inequality. My brain took me automatically to the wiki page about the machine monsieur Guillotine popularized. Now YT is offering videos of these guys. I consider my journey a time well spent!
Maybe they purposely made the blades less efficient so it would be more horrific
10:30 the comedic timing on that rooster cry...
a lot of people with a lot of suggestions, but honestly your methodology was fine your equipment was just malfunctioning. The bearing assemblies are good, they just need to be longer. They can't resist the turning torque because they are too close to the source and don't have enough leverage. Making the carriage longer, and putting additional rollers on the end, would provide higher resistance but would give far better mechanical advantage to resist the cutting induced torque. An example would be something like a shaper, which has a very long rail compared to its cut/stroke depth, often less than half. This is because all the extra interface between the carriage and the rails allow for far higher rigidity, far better predictability, and less deflection at the cutting edge.
OH and try to constrain the mats, and dont forget to soak them in water. IIRC the tatami mats are supposed to be soaking wet for cutting, although that may be lies fed to me by internet strangers.
I also thought that the wheels might be too close together, spreading them out might be a good idea.
Looking up some guillotine images, the rail system seemed to have longer spread as well, for most of them at least.
good list thanks
Appropriate avatar of Ernesto Guevara, since he was in charge of executions in the La Cabana Prison in Havana. But by firing squad not guillotine.
@@LouisEmery tbh I just look like him and thought it was funny, although a lot of people have a lot of either very awful things to say or very interesting things to say. Your comment was definitely of the interesting variety lol
I think the problem with that idea is they're not using it at it's max velocity/height. At a higher velocity, it has a lot more energy and much less time to rotate.
5:05
"They were used occasionally. Not All day everyday."
me: "Robespierre would like to disagree."
Yep hundreds a day in some cases.
As I remember they had to throw buckets of water on the blade at one point to keep it from warping. But as I understand it, at the height of the Revolution, sharpness was not a consideration. Maybe in the original design, but not as a matter of practicality.
Was just thinking "Not used all day" Robespierre: "Am I a joke to you?"
#1 no head hole, a real guillotine has a board with a hole that prevents the neck from moving to the side. Without it the cut object moves away both losing energy and eliminating the slicing effect from the blade being angled
#2 bracing the rails in a few places to make them wobble less. You can see the wheels losing contact, this lets the blade come in at an awkward angle and makes it easier to hit the wood.
#3 using a very thick sausage with a skin like a giant salami/mortadella would be a good idea because its internal structure does not slide about so much and it has a skin. Maybe even wrap it in pig skin for better effect. Having to cut the skin does make it more difficult and an exceptionally bad blade design would be more likely to achieve crushing damage instead of a cut, because it will mash all the interior but won't go through the skin. There are about neck-thick mortadellas and salamis but they are expensive.
thanks!
Iv sometime seen in historic text that there was a collar attachment that came from the top to hold the head and neck in place. Like a clamp.
I believe the 'head hole' was called a 'lunette', used to lock the unfortunate victim's neck in place.
The catchment at the bottom that the blade slots into doesn't need to be very close together. You can easily fix some of the wood-hitting just by moving those further apart. (Though, that may mean making the carriage a bit thicker).
Can't wait for round 2!
The historical blade you guys measured was more symmetrical in weight, maybe that influences the balancing?
This is what I suspect as well. Anything that minimizes the blade rotation should limit travel friction, and even a small increase in friction can make exponential differences in the results as it deflects energy sideways over the full length of the cut.
This would go a long way toward explaining the similar results between the traditional and flat blades, as the flat one is better balanced.
the mounting is way bettre as well. As it is hold in place at the lowest point
So the variability in thickness that Know Art attributed to less advanced smithing technology was actually a deliberate design decision? Cool.
@@faceoctopus4571
No they mean because it's a long strip mounted at an angle, it's the same width all the way across. The angled blades in the video have more material on one side than the other.
I am not sure that the weight distribution matters, if anything, it should be an advantage. During the fall, it is essentially a free fall, especially with modern bearings, so no significant torque would be applied. However, once it hits, the thick, heavy, part will hit first, limiting initial rotation because the center of gravity will be closer to where the force is applied, limiting torque.
You may take note that the (potentially used) guillotine blade is much wider, and it's carriage was probably not a set of complex rollers and what looks like 3D printed plastic, but a frame or two pieces of wood fitted to the ways of the frame. Yes, this will result in more friction losses than rollers, but it would also make it impossible for the blade to significantly turn aside from the cut. You can torch blacken and then sand and polish the frame to make it's surface a bit smoother and harder than the sliding blocks which will help to prevent binding and friction.
*Edit, the tatami mats you were using are best at simulating flesh when they've been left to soak in water for some time, tie the ends of your test piece together tightly with chord and soak the whole thing in water for a good amount of time before cutting it. This will make it expand and build some tension in the fibers which will make it as flesh-like as a mat of plant fiber can be.
The Brachistochrone curve should be pointed in the middle with curves going outward from the middle on each side just like the pointy blade. That would make more sense since usually the object being cut doesn’t start from one side but rather from the middle.
great idea thansk
@@KnowArtwhat about the reverse of the brachistochrone blade? Not the mirror but the inverse of the curve.
I think that would be a little too pointy for a blade you want to chop things with. Imagine trying to cut a slice of bread with a shape like that.
I bet on
Or have the curves come in from both sides together, which will preserve the speed benefit without the weak point in the centre.
We love your videos and thanks to the lack of loud and annoying music and soundeffects my partner loved it too. thanks to you i was able to share a common interest that's otherwise often lost to too much noise. so thank you for investing time and effort in presentation and research rather than effect and editing.
18:32 Imagine running into two guys picnic with a guillotine in the wild, I'll run to the hills.
That timestamp does not even exist in this video.
But...if you ran across them having a picnic, wouldn't you already be in the hills? Maybe you should run to the civilization?
Good luck finding them in the Nether lands.... 8-)
that doesn't even exist, wth
blud timestamp after they make the video 💀
Nice video, I enjoy the "explanation style" - calm voice, well structured thoughts and, most important, no stressful action-music. Thanks for that!
I like how you do ad reads, it surpasses the rest by making full use of your screen rather than stopping the whole video for said read. You also use sponsors as comedic relief using adam and ev- ahem, i mean through ingenuity
thanks!
I appreciate the fact that you actually read everyone's comments and noted their suggestions. Most youtubers with a channel of your size do not go through that effort.
The tatami you are using are indeed used for katana testing, but please be mindful that they need to be wet (not soaking, but moist) to properly be used.
as long as they are consistent between tests it's all good for us, I believe. I didn't want them to dry out throughout the day, so I kept them dry to begin with
@@KnowArt ah. that makes sense, but I belive the standard method is to just keep them in a bucket or something when you're cutting others- they don't work as well if you don't soak them
you also want to roll them farily tightly- I think?
They are meant to be soaked overnight and then be left to dry to not be soaking wet afterwards. Even with your consideration the result may vary drastically.
Imagine trying to chop a piece of firewood with a 10% moisture total or one with 60%. That is quite the difference.
@@KnowArt They also need to be secured. You just rolled them without tying them together, which allowed them to unroll with variable results
1:41 goddammit why did it help 😭
hahaha
😂😂 "ah yeh I know what a bald eagle weighs but not what a kilogram is"
@@SotGravargI have seen many bald eagles. I have seen very few things measured in kilograms
@@cal593 A kilogram is when you have 1000 grams of weed.
@@cal593 1000 kilogram is when you have 264.172 gallons of water, cuz 1L is 1000 grams which equals 1 kilogram and 1000L is 1000 kilgram or 1 metric ton. Also 1111 1/9 9mm bullets next to each other equal 1m in length, 1 cubic meter so 1111 1/9 9mm bullets in Y, X and Z axis equals 1000L of volume.
The guillotine you showed from the museum, was of equal width, not having the issue, of imbalanced weights,
while in your prototype you use an entire right-angle triangle,e which makes it bend, so yeah try the. one similar to the museum for better accuracy,
great work btw.
You could also adjust the balance with well-chosen cutouts. Alternately, you could bolt extra bits of metal on to adjust the balance.
Thank you for this excellent video! For part two, I'd recommend using pipes and grooved pipe wheels (possible on both sides) to improve carriage stability and having some sort of brace for the target to avoid slippage/rotation (this shouldn't be a huge issue, but it's still a variable that shouldn't be ignored). Anyway, I can't wait for part 2!
Love the how the sheep is intrested too lol 7:04
this goat is a lovely old lady :)
got a little spooked when he said "let's test the guillotine blades" while petting the sheep. bro doesnt know whats coming for him 💀
At first I thought they are going to test it on the sheep
They always use it on Sheeple. 😮
As a future guillotine builder I appreciate all of the work you have done. You have illuminated a bunch of engineering considerations I'll have to keep in mind in the future.
One flaw is the Mass is not fixed, so the potential energy is higher and also it's inertia.
Also I think the original is angled because it allows one side of the blade to slot in between the wood thus aligning it to not hit the wood.
That makes a startling amount of sense.
Mass is constant, all blades are exactly 10 kg. Proper Printing emphasized on this and showed how they added ballast to bring mass deviation to under 100 grams.
Why would a straight blade not be abke to slot in between the wood?
@@JosGeerink Any blade shape can be slotted into tracks along the edges, the thing with the slanted blade is that leading edge is the part closest to the track, thus the part subject to the least wiggle.
First watch of your lecture and I am in. I really like how you bring the assumption of some technical knowledge but still use real examples. Thank you kindly for sharing.
While the Imperial Bald Eagle is still the most common unit of weight and mass in most of the US, in industry, we've been using decimal B.E. since WWII. Not quite as modern as the Dutch Decimal Lion, but it gets the job done.
lol
7:02 Heavy super villain vibes. A man with a fancy accent sitting calmly talking about a guillotine while petting an goat.
lol
Don't let the french know about this
They invented it, so they know about this already 😂
Really? I had no idea @@nephastgweiz1022
@@nephastgweiz1022 Don't let them know someone is making one nowadays 🤫
too late
Oh we know 🇫🇷🇫🇷🇫🇷🇫🇷🇫🇷🗣️🗣️🗣️
You need a much longer carriage to prevent tilting on impact with the angled blades.
7:00 "Let's just build a..."
Goat: "Yay I want to try it😊"
haha yeah I was thinking like, goat, you have no idea how bad your timing is right now
Wait a minute. All the years I have been clueless about compressing the material and cutting from the "easy" side. Thank you!! I will take this to the test when I cut that giant bush in front of our house this fall And hopefully the shears won't randomly get stuck anymore.
You forgot a shape. The inverted pointy. Like an open pair of scissors getting slammed down that will focus the cutting power inward towards the middle.
And in the middle it'll crush I guess. The pointy forces outward forcing cracks or cutting, inward makes it crack or crush. Let's say it makes the target material denser and denser stuff is harder to cut
00:16:30 Should I add weight to the pointy end to help keep momentum even?
wdym tested....
“Not used all day every day.” Many Frenchmen would say otherwise in times past. Prediction - the highly concave curve will progressively increase resistance, as the top is practically flat. Necks were restrained too. Great video! 👍🏻
nice lemonade stand you got there
“We will build a full sized guillotine-“
WOAH WOAH WOAH WOAH HEY THERE-
yeah wtf XD
You work for the government??? No need to worry then...
i love the goat coming up for pats, heel schattig
heel lief geitje
5:30 I think this example is somewhat faulty. When you cut a cucumber, or most other foods; with a knife, you don’t tend to bring the whole blade down at once. You place the tip of the knife on the cutting board and chop it down onto the food. In such a case only some of the knife interacts with a small section of the food at once and moves across from there, which I think is similar to the effect of an angled blade.
As someone who has built industrial guillotines, I can tell you, you need to make the carriage taller than it is wide (2 to 1) and you need a tighter fit between the carriage and the guide rails. I had to do some experimenting when I designed my guillotines, and found that a 5 to 6 degree angle on the blade with a 15 degree bevel worked best for cutting through the material I was working with - polyethylene plastic. Obviously, the blade needs to be designed for the material your cutting through.
What do you mean you designed "industrial guillotines"? Are you a 300 year old french engineer?
@@ral008 Yes, I'm a 368 years old Parisian😜. But, seriously, the style of cutters I have designed and built are generally referred to as guillotines, in industrial applications, because the blade moves vertically in some sort of guide; however, rather than gravity power, they use pneumatic or hydraulic power. I even built one that cuts in both directions - up and down.
@@stevencooper2464 so like those big machines that cut stacks of paper into size for example
@@ral008 Yes, a good example.
5 or 6 degree blade angle is really quite low! I'm surprised that's noticeable at all
The design of the 45° turned posts for the carriage/sled is so elegant! Self-Centering!
I'll tell Jón! He'd love to hear someone appreciate it. thanks
i think you should have fixed the mats, like the heads didnt have space to move as well during those times so it may change things if you didnt allow the mats to move
thanks! might try that
People already addressed your apparatus problems, and much better than I could.
I think you should also add a convex brachistochrone blade. Most weapon blades (and modern tools) designed for slicing used convex cutting edges
Glad to see Rusty Cage isn't the only one that made a lemonade stand.
I'm really a fan of this much more laid back editing, keep it up!
The necks back in the revolution didn't have to deal with rotating because they were fixed in place by the wooden cuffs.
I absolutely enjoyed the video and look forward to part two. I have a few things to say about methodology:
- the mats are meant to be watered.
- there are devices to measure sharpness (e.g. bess). Would be great to verify the blades are similar in sharpness.
- fixing the mats in place would prevent many factors of interference. Also it would be more accurate.
At 0:12 is that a Puch or a Tomos ? well on with the video
tomos apn 4
haha no clue sorry
My god someone knows Puch ❤
When I worked for a commercial press (printing company), they used modern guillotines, which uses a hydraulic piston to press the knife's blade through the substrate quickly, and then then raise it back up again, ready for the next cut.
2:49 Bro, who has that much butter lying around? Or where can you even buy a block that big? That's gotta be like 1.25 bald eagles of butter!
it's a weird perspective but it was just a regular piece of butter. 250g I believe
My man you are a fascinating speaker, I was entirely engaged the entire video.
All i know they are probably gonna make a comeback
There is a couple of things that I can add that, while not necessarily helping or hindering your results, will provide extra consistency to the results.
First, tatami mats, when used as a cut testing medium are supposed to be soaked in water. This will soften and tighten the fibers as well as making them much less likely to just break when pressure is applied.
Second, the mats need to be bundled tightly and bound so that they don't unroll or unravel under the pressure of the blade landing on them. Unbound and loose as you had them here, the spread of the mass of the tatami could move around making some portions of it easier to cut, and being that they were dry, it made the whole thing easier to just break rather can be cut properly.
It may only provide a minor difference, but in science, consistency is important! Hope this helps.
theres a fire alarm beep at 1:36
hahaha hadn't noticed that. I'm pretty sure it's audio from in the museum archive where someone's shoe squeaks on the floor that I forgot to remove
The Gevangenpoort had a truly Dutch torture. The prisoner was held, without food, above the kitchen.
12:44 i see you are a man of culture as well 😌
haha it's a literal translation from a dutch saying
Lost in translation
English doesn’t feel as punchy
Interesting video! The main difference I can see between your angled blades and the historical one is that due to its geometry, the historical blade was fixed to the frame near the edge on both sides, which prevents the blade from rotating on impact. I think if you try attaching the blade to the frame near the bottom of the blade on both sides, the angled blades will perform better.
the tatami mats are supposed to have a bamboo core and be soaked in water for a day to mimic a neck...
Save this video b4 youtube takes it down, this is a gem!!!!!!!
thanks! I don't expect problems from yt
Part two: Testing ALL of Guillotine Blades On a Living Human! (you won't guess what happened next)
*sirens*
Ballistic mannequin could be fun but a bit out of the budget I guess
This was....very interesting. Really enjoyed the walk through the scientific method with you.
if there's too much weight on one side with angled blades, the fix is simple. add enough weight to the light side balance it out. This will keep the blade straight at least until impact. To avoid the blade tilting on impact, you could add even more weight to the light side, but then the blade would tilt in the opposite direction during the fall.
You partially did this when you added a piece of wood to the flat blade to compensate for weight difference, but instead you'd have to account for how much extra weight is on the heavy side, to add it back to the lighter side. If all blades are to be the same weight, then you'd have to recalculate how to cut the blades, so that you can add the extra weight after you have the blade shape.
Check with woodworkers. They can show you that skewing the blade is easier cutting.
Slicing cuts are cleaner cuts than chopping cuts.
5:07 the French…
was looking for your comment lol
Ever since the whole rusty cage arc youtube thinks I'm obsessed with guillotines
"About 2 bald eagles for our American friends" Man, I don't know anybody who has ever held a bald eagle lol
Awsome! Well done! Both with the experiment and the editing! Love the sheep pat!
Well the angled guillotines were made like that to cut better, if its flat it would be stuck on the poor dude.
As an American, I really appreciate the bald eagle reference. Any laugh I can get these days helps Thanks.
i didnt know i needed this video until now. cant wait for part 2!
If you're looking to test edge shapes and angles specifically, I'd build the frame out of steel instead and increase the length of the carriage to provide better resistance to the blade trying to rotate. Wood can get pretty flexy, and your blade trying to rotate will try to push the rails apart. The more the rails flex outwards, the more misalignment can happen, further exacerbating the initial clearance issues, causing the carriage to wedge itself against the rails harder. A solid set of rails and a carriage with bearings spaced farther apart will help minimize the losses of the carriage wiggling around and trying to press itself into the rails with the uneven loading caused by an angled blade.
As others have said, constraining the mats could also help prevent some losses due to shifting, as could tying the mats tighter to prevent whatever shifting you can. Pretty easy to accomplish both by just clamping em in place a couple inches from where the blade strikes.
Not sure if the blade wedging the carrier against the rails or the mats shifting out of place is causing more losses, but pretty sure that each of them is doing their part. The v-shaped blade certainly helps both of those though, which I imagine is part of why it did so well.
This is what cracks me up...
This gentleman is expolating fact with suggestions for improvement...
Along comes all the internet's self proclaimed authorities on the subject.😆
nicely done on the sponser part of the video. was gonna skip but u got me with the split
thanks! good to hear
I appreciate the amount of effort you put into the quality of the content and video. Just please consider adding more quality to your audio.
first time im seeing this channel and i think i may have a new fav yt channel now
This is weirdly super relaxing to watch.
great video! i really like that you do practical videos besides visualised theory
The transition to the ad read was really good.
Looking at your slow-mo footage , I have a few suggestions .
First , roll your mats tightly . If you compare your mat footage to the meat you cut , you'll notice that the meat has very little give . The mat x on the other hand , is absorbing a lot of the impact before giving the blade a more solid surface to cut through .
Second , if you look at traditional guillotine designs , there is either a hinged stock with a hole for the condemned person to out their head through , or at the very least a rounded trough for their neck to sit in . Both items do the same thing , keep the neck stable and secured as the blade passes through . Watching your footage , your mats tend to roll for every blade but the flat or double bevel as the force is focused straight down on those 2 designs .
Third , I'd design your blade carriers so that they push into the uprights slightly to alleviate the side loading issues you had . You might try making them longer so that whatever sideways force is applied is spread over a much longer area .
Interesting exercise. If you're only interested in blade design, I suggest a VERY robust, rigid, low-friction, metal frame with a lubricated metal slot in which the blade travels. Use a long, symmetric blade frame designed to minimize blade rotation for asymmetric blades. And a semicircular well or adjustable side constraints for the mat bundle to prevent lateral movement of the target. Also make the blade slot under the target wide enough that the blade NEVER contacts it. If you want to get geeky, interface a 1000g accelerometer to an Arduino and read it at about 10kHz.
Would it not be better to have a straight channel groove cut into either side of the tower beams that guide the blade the entire time, and doesn’t allow the blade to rock left or right like your rollers are allowing it to do? I understand that the rollers reduce friction, but you are also allowing for a lot of extra movement in the blade. Giving the blade a dedicated channel to follow would prevent the blade from deflecting off of the material that you are cutting.
And as I see others have mentioned, fixing the material in place would prevent uneven cutting.
And lastly, I know it’s expensive, but ballistics gel would give you a more consistent result, rather than the matting.
Eliminate all of those unnecessary variables, and I think you’ll find the slicing motion of the angles blades would be more effective than a flat blade. Though, I do think you’re onto something with the brachistochrone blade.
Im interested to see what changes you make in the future, just subscribed. 🤙🏻
Edit: thinking about it a few minute later, it would be easier to just install two pieces of angle iron on either tower beam, to create the channel. Rather than cutting grooves in the wood. Space the angle iron a few mm larger than your blade thickness and you’re in business. Far less deflection of the blade, and you won’t miss your slot in the bottom.
I would like to applaud you for how you presented your sponsor segment. Usually I just skip that part of any video, but by having a VO and actually interesting footage I watched the whole thing. Good Idea and I wish more people did that.
I was about to come into the comments and say something along the lines of "as per the cutting theory explanation you provided earlier in the video about how slicing with a horizontal motion creates tension in the material which makes it easier to cut, a reason why the angled blades didn't perform as well as expected is (I assume) probably because the mats were rotating as they were being sliced, reducing a lot of the tension from the mat as it's being cut, whereas someone's head is fixed in place in a guillotine where it cannot move like that, therefore tension is maintained throughout the entire cut," but then I see that many people have already said something similar haha
What a convenient and timely recommendation.
Another thing to keep in mind(at least with using tatami) is that the mats are meant to be soaked in water overnight in order to provide a more accurate simulation of a human neck/limb.
5:25 This is a really good point and it took me a minute to realize the alternate explanation. Sliding a blade along a surface to cut it in a slice is different than a chop. The 45 degree angle more closely approximates slashing a long blade across the target, rather than whacking it like an axe.
if you're a carpenter you already know what the difference is. if you're working with a plane, you can use something we call a "pulling cut" (literal translation from geman), which is angling the plane so that the blade makes a slight sideways motion in addition to the forward motion. it makes it easier. working with a plane is hard work!
As an ex cook I can tell you that the problem is the bone. Normally with a flat cut you can fail to make a clean cut, it has to broke it in only one opportunity. The angled shape make's a cut from the side (with the flat one you make a cut with 5 cm of the blade, in 45° you make a cut with something like 7 cm). If you try the pointy blade in bones you have a high risk to break the blade. The bone is the secret, you can ask to any japanse swordman why katanas got that shape. The idea is to avoid to get stuck on the bone (and if it does, it make's it easy to remove). The other thing is the only one sharp side blade, it's used to make the blade thinner and avoid the cutted element to get glued to the blade. It's used in many japanese professional knives. Your video is really interesting.
Suggestions:
1. Make something that holds the thing in place so it can't move as it's being cut.
2. Make a bigger hole for the blade to go through so it doesn't hit the wood.
3. Make the blade wobble less, this can be done by increasing the length of the gantry.
0:36 Nice Puch moped in the background! ♥️
As a Floridian I gotta thank you for giving us the weights in eagles. People in Florida famously can’t read normal units, neither metric or imperial.
Don't forget that when those Old Dewds would cut your neck off, you'd put your neck in a rounded trough, and a matching piece would slide down on top to act as a collar, fixing your neck in place with little room for movement. That would 1) keep your neck from rolling/twisting as any slanted blade would apply torque, and 2) keep your neck from sliding away laterally as well.
The mats in the test were free to turn and be pushed aside, which is probably what screwed with the readings. Even fixed pegs on either side holding the mats in place would help prevent that.