Why are guillotine blades angular rather than rectangular shaped?

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Guillotines chop heads. If you look at the guillotine blade, it is angled, with one side of the blade much higher than the other end. I would think the guillotine blade would be shaped more rectangular.

In: Engineering

18 Answers

Anonymous 0 Comments

When you chop vegetables or fruits, do you knife those things parallel to the chopping board?
Or do you tilt your end a bit higher?

Anonymous 0 Comments

Next time you shave, if you can shave, angle the blade just slightly. Not as much as a guillotine, but just slightly.

Anonymous 0 Comments

you want more slice less choppy chop. think about cutting a tomatoe. if you just bring the knife down on it, even if its super sharp, it will bruise and squish the tomato. if you cut in a slicing motion, that tomatoe slice is just fine and ready for a sandwhich. just like a guillotine that is angled is ready for a revolution.

Anonymous 0 Comments

I feel like this would be a pressure = force/area thing. So if the full blade makes connection at once, the force is evenly spread over a larger area.

Kinda like how if push on a peice of wood with your thumb nothing happens. But apply the same force with a small area (like a pin) you can push into the wood.

So by having an angle, you have the same force on a smaller area at the start, so a much higher pressure.

Anonymous 0 Comments

i can explain this like you are a five year old. Take a butter knife and take a tomato and chop straight down into it. It’ll squash it, juices and seeds will leak everywhere. But hold the knife on an angle and slide down into the tomato and you’ll get clean cut. Concentrating the pressuring into one point of the blade on an angle is better than trying to spread the same amount of pressure across the whole blade surface.

Anonymous 0 Comments

I’m not a historian, and you might want to ask this question at r/askahistorian, but I some blades were flat at the bottom, and if I’m not mistaken some were triangular, so the point was in the middle. The engineers that design this sort of thing figured out pretty quick that the angled blade works best. Take for example a great loaf of bread if you took a sharp flat blade and brought it down on the bread would it cut? Yeah, maybe but there is going to be a whole lot of smooshing going on too… not good… the point in the center blade would direct the force out to both sides of the retaining block which holds the head in place, allowing it to slice but also smoosh, there are stories about the blade not going all the thru and the executioner having to jump on top of the blade to get it thru… ( I think I heard that on hardcore history)
The angled blade was perfect, as it dropped it pushed the neck to one side of the retaining block and allowed the blade to cut smaller amount and still get the job done…. I think I’m close, others much smarter and more awake than I would probably have greater insight …

Anonymous 0 Comments

A straight blade such as a rectangular shape is designed for chopping, while an angled blade is designed for slicing. The human neck is not hard to cut through, but there are pieces that are tougher than others (the spine for example). Imagining a tomato, the skin is tougher to slice than the flesh. Imagine taking your knife, flat against the skin and pushing down. It would squash the tomato, not cut it. Now imagine the same scenario, but you angle the knife in the direction of the resistance, suddenly the skin and flesh of the fruit becomes much easier to cut in one clean slice. A guillotine is the exact same concept. It’s a slice, not a chop.

Anonymous 0 Comments

So that it actually slices as it drops. If it was rectangular, the cut would be a lot more brutal and gory.

Anonymous 0 Comments

the angle of the guillotine not only change it from a chopping motion to a slicing motion, but increased the cutting surface and increased the cutting speed significantly. Since the blade is at an angle to the cutting surface the cutting edge will pass through the object at a much faster rate then if the blade was parallel.

Because Science did an episode that explains very well. 8:25 showing that the cutting edge of a guillotine moves much faster than it falling.

[https://youtu.be/YlpiV4suBNA](https://youtu.be/YlpiV4suBNA)

Anonymous 0 Comments

Literally to ‘Slice’ the head off… much neater, more chance of the head coming clean off vs a blade coming straight down in an axe motion.