Sequeira Eldrid - 3D Printing and Maker Lab for Kids

5. Mixing different types of materials (metal, fabric, organic, etc.)

The process of 3D printing is essentially a manufacturing technology to create objects in three dimensions (as opposed to 2D printing of documents on paper) using various materials heated to a temperature that allows them to be formed into different shapes. It has gained much popularity in the past couple of decades due to the abundance of reasonably priced desktop 3D printers available on the market and in local libraries. It is a convenient way to create prototypes or customized items, or to create replacement parts for household items (some of which are discussed in this book).

There are many types of 3D printing; however, the one discussed in this book is also referred to as additive manufacturing. The 3D printer essentially lays out material in two dimensions and then keeps adding layers on top of the previous layer to create a three-dimensional object. The material (filament) is fed into an extruder where it is heated to about 215C, at which point it melts and the extruder pushes it out of a nozzle, much like toothpaste squeezed out of a tube. The extruder moves in three directions (left-right, front-back, and up-down) based on a sequence of commands that are determined based on the design. The design is usually created in a software separate from the printer (such as Tinkercad or Sketchup). The software file once completed is sent to the 3D printer software which interprets the software file that the 3D printer can understand. The printer software converts that into motion commands for the extruder. Most 3D printers will let you pause the printing midprinting this is a good way to see how the printer has determined the internal design of the object. Printers are shipped with various default settings to minimize the time and material to print objects. However, most printers will let users modify the default settings, so you can choose the temperature to heat the filament, the thickness of the outside walls, the amount of infill, the pattern of the infill, and other details.

3D PRINTING PROCESS

Typically, we use polylactic acid (PLA) plastic filament for printing, but this might vary slightly depending on the printer you use. There are many models of 3D printers, but in general, these are the steps necessary before printing a CAD creation:

Ensure the bottom surface is touching the printing bed; if not, click the black arrowhead and drag it down till it indicates 0 mm (fig. 1).

FIG. 1:To ensure that the bottom of the print item is touching the printing bed, click and drag the black arrowhead to 0.

Export the design to the 3D printer.

After the printer software has processed/sliced your design file, check to see whether the first layer of each element is sitting on the bed, or on another element (fig. 2).

FIG. 2: