If I cut a thing in two, are the two pieces together exactly the same size as the original?

Or to rephrase it: does a knife/scissors/etc just split something or does it remove something?

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[–] 12 points 11 months ago (2 children)

This is pretty much what I was going to say. You always lose material, but the amount lost varies drastically based on the method. Even when using a knife or shears in a purely straight motion (no sawing or sliding), the material has to deform to make room for the cutting device. It may rip apart, it may bulge into itself, it may crumble, it may do it all. Try cutting a thin slice off a nice block of cheese and you'll see nearly all the deformation go to the slice, while the knife will be coated in cheese

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  • [–] 4 points 11 months ago* (1 child)

    Came here to say this but you covered it pretty well! So I'll just leave this image of steel being "cut" under an electron microscope. You can see the deformation and change in structure.

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  • [–] 2 points 10 months ago

    That looks like my cheddar! That's why, without the aid of an industrial shearing rig, I have to hold the knife at about 15 degrees off vertical, cutting edge towards the block. The cut goes straight down. I've accepted the superiority of using a small santoku knife and having to hand wash. I really should get a wire slicer

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