What is Cutting: Definition and 128 Discussions

Cutting is the separation or opening of a physical object, into two or more portions, through the application of an acutely directed force.
Implements commonly used for cutting are the knife and saw, or in medicine and science the scalpel and microtome. However, any sufficiently sharp object is capable of cutting if it has a hardness sufficiently larger than the object being cut, and if it is applied with sufficient force. Even liquids can be used to cut things when applied with sufficient force (see water jet cutter).
Cutting is a compressive and shearing phenomenon, and occurs only when the total stress generated by the cutting implement exceeds the ultimate strength of the material of the object being cut. The simplest applicable equation is:

stress

=

force

area

{\displaystyle {\text{stress}}={{\text{force}} \over {\text{area}}}}
or

τ
=

F
A

{\displaystyle \tau ={\frac {F}{A}}}

The stress generated by a cutting implement is directly proportional to the force with which it is applied, and inversely proportional to the area of contact. Hence, the smaller the area (i.e., the sharper the cutting implement), the less force is needed to cut something. It is generally seen that cutting edges are thinner for cutting soft materials and thicker for harder materials. This progression is seen from kitchen knife, to cleaver, to axe, and is a balance between the easy cutting action of a thin blade vs strength and edge durability of a thicker blade.

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5. B Why are serrated knives more effective than normal knives?

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6. Force & energy in cutting and stretching magnetic field lines?

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7. B Blunt force vs cutting force in penetration

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10. Shearing / Cutting Force - Rubber bale

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11. Why have a feed force in the cutting process?

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12. Shredder Cutting Area Calculation

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13. MHB Calculating amount left at the end of a repetetive cutting down cycle.

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14. Steel chisels cutting wood and bone

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15. I Adhesive force between cutting oil and metal chips?

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16. Formation of a hyperbola using a plane cutting a doubole con

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17. B Force at which a cutting disk comes off from an angle grinder

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18. B Problem about a cone and plane cutting it

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19. Studying My current study habits aren't cutting it for me at the moment

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20. Flux with an infinitely long surface cutting through a sphere

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21. Force required for cutting sheet metal

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22. How can we reduce food waste at home and beyond?

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23. Designing a Log Cutting Mechanism - Get Suggestions Here

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26. Cutting magnets without losing magnetization (Curie temperature issue)

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27. MHB How Can I Efficiently Cut Wood Boards of Different Lengths?

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28. Misc. Custom building a CNC mill for aluminum

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29. Calculate cutting force (guillotine) GFRP

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30. Cutting a Groove -- Power Requirement

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32. I Matter cutting by destabilising of atoms bonding

is there a theoretical way to cut solid mater by disrupting the electron field holding atoms together
33. Force required for cutting process

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34. Resources on Gear Cutting Machines

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35. Cutting force (large astronomical body)

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36. Cutkosky Cutting Rules: Understanding Rules & Where To Add i

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37. Calculating bend moment of a rotating cutting tool....?

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38. Finding the work done on a cutting tool

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39. Shearing Force - Cutting Force

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40. Precision Cutting Jig Options for Brass Tubing: Buy or Build?

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41. Cutting a spring in half and then in 1/4 and 3/4

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42. Regarding volume of an ellipsoid bounded by 2 planar cutting planes

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43. Cutting, at the atomic/molecular level

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44. MHB Cut 16" Pizza into 3 Equal Pieces Using Calculus

Here is the question: I have posted a link there to this thread so the OP can view my work.
45. How to Achieve a Clean, Perpendicular Cut on a Plastic Rod?

Hi everyone, I have a plastic rod that is cut/snapped between two metal clamps. I want the break in the material to be at an angle perpendicular to the rod's surface. Can anyone tell me what factors effect this operation? How can I select the best material for the plastic rod? Thanks in...
46. MHB Maximizing the volume of a cone formed by cutting a sector from a circle

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47. Wire cutting magnetic field lines

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48. Homeomorphism through cutting and pasting of manifolds

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49. How difficult is cutting hair?

Hi Everyone. The place I have been going to for the past 8 or 10 years to cut my hair closed down, so I went to the barber's around the corner. Now for as long as I can remember I've always had the same haircut: a number 4 clipper (or whatever the attachment is called) on the electric shaver...
50. Cutting speed, Spindle Speed Calculation for shafts

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