Desktop 3D Printers

Definition

the formal definition of 3D printing, or “additive manufacturing” as defined by the ASTM International Committee F42 on Additive Manufacturing Technologies3 as,

“process of joining materials to make objects from 3D model data, usually layer upon layer, as opposed to subtractive manufacturing methodologies.”

Source: ASTM F2792-10 Standard Terminology for Additive Manufacturing Technologies

Description

Hod Lipson and Melba Kurman:

"3D printers use as an additive process, meaning they make objects by systematically depositing a chosen raw material in layers. Somewhat similar in concept to that of an inkjet printer that orchestrates different colored print cartridges to form an image onto paper, the most common household 3D printing process involves a “print head” that works with any material that can be extruded, or squirted through a nozzle. Another common type of 3D printer uses a laser beam or glue to selectively fuse powdered plastic, metal, or ceramic raw material in layers.

...

Industrial size 3D printers cost up to half a million dollars, but low end personal-scale 3D printers cost less than $1000." (http://web.mae.cornell.edu/lipson/FactoryAtHome.pdf)

Materials

"The most commonly used material in 3D print applications is plastic, but some higher-end machines are able to work with metals and ceramics.

...

Today’s 3D printers are already capable of combining and manufacturing previously incompatible materials, namely simple electrical components and mechanical parts, called electro mechanical devices. (Your cell phone or laptop (or Roomba) is made of electrical and mechanical parts that were manufactured on separate, specialized machines and assembled afterwards by yet another machine, or human factory workers)." (http://web.mae.cornell.edu/lipson/FactoryAtHome.pdf)

How-To

"The 3D printing process works as follows. Once the user has selected an electronic design blueprint and loaded up the raw materials into the 3D printer, the machine begins its work. In a process that can take several hours to days, the 3D print head deposits layer upon layer of tiny droplets of raw material to form the object. Depending on the complexity of the design, the machine is able to switch between different print heads to work with multiple materials and form shapes with a number of colors and diverse textures. Eventually, after countless back-and-forth sweeps, a three-dimensional object forms out of raw material." (http://web.mae.cornell.edu/lipson/FactoryAtHome.pdf)

Advantages and Disadvantages

Hod Lipson and Melba Kurman:

'* 3D printers appeal to artists and designers since their unique layer-upon-layer production process enables creative people to precisely fabricate imaginative and unusual objects, according to exact blueprint specifications.

• 3D printers are clean,

meaning since their manufacturing process does not involve cutting, scraping, or burning a raw material, they produce very little manufacturing waste, or un-used byproduct.

Due to their precision and versatility, 3D printers are already in use in industry for industrial modeling, product or part visualization, and prototyping.

...

• Almost any physical object that can be sliced into thin,

horizontal cross-sections and represented in an electronic blueprint can be 3D printed.

• Another characteristic of 3D printers which makes them uniquely versatile is

their ability to simultaneously print, into a single object, previously incompatible materials.

• When working with raw materials that are chemically incompatible, or that require

different manufacturing conditions, traditional manufacturing machines must work on the incompatible materials in separate processes and then assemble them later. Since 3D printers form objects layer by layer, they fuse together multiple materials into a single object at the time or printing. As a result, in a single “print job,” a 3D printer can combine materials that have different physical properties to produce, for example, a plastic hair brush with soft-bristles set into hard plastic.

This “co-fabrication” process is not unlike biological growth, where hard and soft tissue is cofabricated and intertwined in living beings of infinite complexity." (http://web.mae.cornell.edu/lipson/FactoryAtHome.pdf)

Disadvantages

• "The main disadvantage of 3D printers is the slow

speed of their unique layer-upon-layer fabrication process. Even industrial-scale 3D printers are too slow to quickly produce large volumes at the rate needed in mass production environments. As a result, 3D printers remain impractical for the production of anything other than small batches of a kind custom objects, complex product prototypes or objects d’art." (http://web.mae.cornell.edu/lipson/FactoryAtHome.pdf)

Areas of Application

Hod Lipson and Melba Kurman:

• "a popular application for 3D printers is that of

custom food and candy. Since it is meticulous and can combine materials in new ways, a 3D printer can create edible materials and custom confections

• As the price of 3D

printers shrinks, consumers are experimenting with the fabrication of novel recreational consumer items such as jewelry and toys.

• In industry, companies print

specialized technical parts for high end electronic and medical products that demand custom precision, such as dental crowns and bridges.

• A vibrant hobbyist 3D printing

community continues to attract a growing number of designers, businesses and consumers.

In the future:

• future 3D printers are able to manufacture very sophisticated

devices that contain fully formed electronic circuitry, batteries, sensors inside some sort of mechanical “body,” we will witness the production of fully formed robots that will not require further assembly.

...

a 3D printer that manufactures a complete robot would qualify as “a robot printing robots.” (http://web.mae.cornell.edu/lipson/FactoryAtHome.pdf)

More Information

• Personal Manufacturing ; Desktop Manufacturing
• 3D Printing
• Desktop CNC Routing and Milling Machines