Subtractive Manufacturing Techniques

Subtractive processes revolve around the idea of material removal, and encompassing techniques to where you can achieve a desired end product.

Subtractive Manufacturing - CNC Machining

Some of the main types of subtractive manufacturing methods are:

CNC (Computer Numerical Control)

  • CNC typically employs drilling, turning, and milling tools to remove excess material and can achieve up to 5 degrees of freedom. This motion is extracted from the design’s CAD file in the form of a program, such as G-code, to tell the machine where to go
  • Used for hard thermoplastics, metals, and thermoset plastics
  • This article dives deeper into CNC operations

Laser Cutting

  • A high-powered laser is used to melt and cut through a material and is guided through a set of mirrors. It typically cuts around an XY plane, with higher dimensions being possible, through thin sheets of a material. Applications depend on the type of laster system used.
  • Materials such as Wood, Fabrics, Metals, Acrylics, and Thermoplastics can be cut through this process
  • This Instructables Post gives a good background on laser cutting and the various types

Water Jet Cutting

  • A supersonic stream of water, sometimes mixed with abrasives for cutting harder materials, is delivered from a nozzle to cut through a material. It’s good for cutting materials that cannot exceed set temperature and it typically cuts arcross an XY plane but higher dimensions can be achieved.
  • Materials such as Metals, Stone, Glass, Plastics, and Composites can be used
  • This article contains a good background on the water jet cutting process

EDM (Electrical Discharge Machining)

  • This process includes a dielectric fluid and an electrode that generates heat on the material being cut. This electrode can take the form of a die, a wire, or a drill depending on the geometry of the cut required and can also achieve high precision and tolerances.
  • Used for metals that are electrically conductive
  • This article dives deeper into the types of EDM and how it works

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