The next step is spray can water fill soil spraying. First, the model’s surface should be washed with water, and then the spray pot is used to fill the soil, before the model is wiped with a non-woven cloth and sprayed at “the ventilated position,” keeping the nozzle at about 20 cm and uniformly spraying the model one to three times, quickly.

“Generally, choose gray spray pot water to fill the soil, because gray is a neutral color,” the team explained.

Figure 10. High mesh sandpaper grinding.

Once the water is sprayed and the soil is filled, air drying takes place. Then, 2000-3000 high-mesh sandpaper is applied for “slight grinding” along one direction, before moving on to the coloring phase.

The 3D printed, polished and processed model should first be washed and dried before pigments are applied. A spray gun can be used to add either a base color or one that covers a large area of the model; you’ll need a 1:2 ratio of diluent to pigment for spraying, and you should be able to adjust the amount of air injection while you’re spraying.

“Brushes of different thicknesses and sizes can be used to paint the details,” the team wrote. “It is accessible to use 00000 pens to paint the detailed parts of the figures, or use different widths of the cover tape to cover and then spray the spray gun to paint.”

Once the paint and spray paint have dried completely, you can uniformly spray protective paint on the model; the research team used B603 water-based extinction for their 3D printed vase.

The team shared a few more notes on making the post-treatment process run smoothly, such as the importance of using software to reduce the amount of unnecessary support structures, coating the print plate with a thin layer of glue to prevent deformation, and observing the model while it’s being printed.

Figure 13. The vase is finished after processing.

“Secondly, in the manual post-processing should look to the protection work, grinding water mill is the best way to model processing, be patient, 80-2500 mesh, use each mesh sandpaper required time from long to short, low mesh sandpaper grinding along the texture of the model, high mesh sandpaper grinding should be turned around,” the researchers concluded. “When mixing colors, you should understand in advance the relationship between light and shade, brightness and purity of various colors, warm and cold color selection, etc.”

They noted that “the degree of difficulty” for post-processing methods, and the methods themselves, can vary with different 3D printing technologies – what works for FDM may not necessarily work for SLA, and so on.

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