<Table> <Tr> <Td> </Td> <Td> This section should include only a brief summary of 3D printing processes . See Wikipedia: Summary style for information on how to properly incorporate it into this article's main text . (August 2017) </Td> </Tr> </Table> <Tr> <Td> </Td> <Td> This section should include only a brief summary of 3D printing processes . See Wikipedia: Summary style for information on how to properly incorporate it into this article's main text . (August 2017) </Td> </Tr> <P> A large number of additive processes are available . The main differences between processes are in the way layers are deposited to create parts and in the materials that are used . Each method has its own advantages and drawbacks, which is why some companies offer a choice of powder and polymer for the material used to build the object . Others sometimes use standard, off - the - shelf business paper as the build material to produce a durable prototype . The main considerations in choosing a machine are generally speed, costs of the 3D printer, of the printed prototype, choice and cost of the materials, and color capabilities . Printers that work directly with metals are generally expensive . However less expensive printers can be used to make a mold, which is then used to make metal parts . </P> <P> ISO / ASTM52900 - 15 defines seven categories of Additive Manufacturing (AM) processes within its meaning: binder jetting, directed energy deposition, material extrusion, material jetting, powder bed fusion, sheet lamination, and vat photopolymerization . </P>

When was plastic models created by 3d printers