Like with all 3D printing techniques, the 3D object must be pre-modeled using a CAD software, such as Tinkercad. The model is then exported to the printing software, which instructs the 3D printer on what to do with the 3D model.
In order to use powder binding with gypsum, a 3D powder binding printer is needed. These printers are made up of two tanks and a platform (bed) where the printer prints the object. When the 3D printing process starts, one of the tanks is empty, while the second tank holds the powdered printing material (in this case, the gypsum). The 3D printing then begins by lowering the platform upon which the first layer of gypsum powder is spread by a leveling roller. The gypsum is then solidified with a binder and colored according to the instructions that have been transmitted to the computer. The platform gets lower and lower, creating a new layer of powder each time, which will then be spread and bound in turn by the binder. Layer by layer, the 3D print takes shape in this way.
The Tinkercad materials guide states that gypsum is also called sandstone, rainbow ceramics, or multicolor ceramics. It is a rigid and delicate 3D printed material, made from powder. Normally, it is naturally white, but it can be obtained in colors for 3D printing as well. It normally 3D prints to about 10 layers per 1mm, and has a 2mm minimum wall thickness. This figure shows you some typical 3D gypsum prints in the Tinkercad materials guide.
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You can download the Tinkercad materials guide, in PDF format.