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Heat Treat & Metals in Everyday Life
Scissors come in all shapes and sizes and are used for applications as simple as cutting paper and as challenging as cutting Kevlar and for everything in between. Unlike a knife, scissors have two pivoted (or hinged) blades. Surprisingly, most types of scissors are not particularly sharp; it is primarily the shearing force between the two blades which cuts.
How They Work
Mechanically, scissors are a double-lever with the pivot/hinge acting as the fulcrum. For cutting thick or heavy material, the mechanical advantage of a lever can be exploited by placing the material to be cut as close to the fulcrum as possible. For example, if the applied force (your hand) is twice as far away from the fulcrum as the...