3D printing, also called Digital fabrication technology or Additive manufacturing is the process of making 3-dimensional solid structures or models from the geometric representation by successive addition of materials. The layers of the printed object are a thinly sliced cross-section of the object. 3D printing is an emerging technology that enables us to produce objects with fewer materials than traditional manufacturing methods. 

The process of 3D printing involves 3 major steps.

• MODELING AND SLICING

It is the first step in the process of 3D printing. Here, even the tiniest detail of the objects is given. The geometric representation of the object is created using software tools called slicing software. The process of building the structure using this software is called slicing as it slices the object to create many layers. The work of this software is to convert the geometry of the object into instructions for the 3D printer. It will tell the printer how to create the layers of the object. In addition, the instructions can also be provided through STL files. STL is a simple, portable object file that is used for designing computer-aided design CAD systems to model the solid geometry of the objects. These STL files are used as the input information for the 3D printers to produce the object. The object is produced by forming layers of the printing material as per the geometric measurements provided. The materials used differ for different technologies.

• PRINTING

When the modeling and slicing get over, the 3D printer starts its work. Assuming that there is no error in the model, the printer begins to print. It dispenses the material layer-by-layer waiting for one layer to get dried so that it could add the next layers. The bottom-most layer is formed first followed by the next highest layers. The model is printed by adding hundreds and thousands of 2D prints on top of one another to make a 3D model. Although many materials are used for 3D printing, thermoplastic is the most widely used one. 

• FINISHING

This is the final and post-printing step in manufacturing a 3D object or model. Once the object is printed and dried completely, a finishing touch is given to remove small damages that occur during the printing and refine the parts. It is done to give a smooth surface finish to the object. Solvents are added to remove the superficial imperfections in the model. There are various methods followed in finishing such as polishing, sanding, etc.

The time taken to complete printing may depend on the size, details, and quality of the object created as higher quality objects take more time comparatively. 3D printing can take some minutes or hours or weeks or even more. For example, it takes almost a few hours to create a simple model like boxes and balls and takes weeks to produce more large and complex structures with more details like buildings and houses. The larger the size and geometry of the object, the longer will be the time spent to create the object. So, 3D printing is useful at the same time, it is a time-consuming process.