In this article, we look at the technology of 3D printing with sand. We’ll cover its principles, applications and advantages, equipment design and technical process. We’ll also look at some 3D printers used for sand printing, and show examples of printed prints.
This is a general introductory article on 3D sand printing.
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History of Sand 3D Printing
The history of sand 3D printing began in the late 1990s with the collaboration of the German company Generis and MIT Z Corporation. MIT developed and patented powder printing technology with the application of a binder. The collaboration between the two companies led to the creation and launch of the first printers in the mid-2000s.
Over time, Generis split into two separate companies, VoxelJet and ExOne. Today, the two companies are the leaders in the production of equipment for 3D printing with bulk materials using the Binder Jetting technology.
Z Corp was sold to Contex Holding in August 2005, and later acquired by 3D Systems on January 3, 2012.
About Binder Jetting Technology
BinderJetting is a 3D printing technology that involves layer-by-layer application of a binder onto bulk material. Using this technology, you can print with metal powder, gypsum, sand and many other materials.
The technology allows you to print injection molds with sand of any complex geometry at room temperature. The 3D printed sand molds can then be used in casting.
The main technology used in sand printing is binder jetting technology. To learn more about the technology, read our article: Binder Jetting: An Overview of 3D Printing Technology .
If you want to know more about the application of printed sand molds in casting, read our article:
Purpose of Sand 3D Printing
Sand-printed 3D models are used as molds for casting metals. Sand casting is the oldest known casting technology. Its origins can be traced back to 1000 BC.
The printing process involves creating a cavity in the form of the desired part, and then pouring molten metal into it.
Sand 3D printing technology has made this process more accurate and convenient than ever before.
How Does Sand 3D Printing Work?
Sand 3D printing begins with placing the first batch of sand in the print chamber and flattening it into a thin layer. Then, the print head of the 3D printer passes over the sand and applies the binder according to the specified layer of the part.
Sand that is not involved in the part, i.e., the san on which the binder has not fallen, serves as a support. This means that the part can be of any complex shape. The process is repeated until the part is complete.
Benefits of Sand 3D Printing
Speed and low cost
The creation of injection molds and sand models using 3D printing is much faster and more cost effective than creating molds using traditional technologies. Traditional, creating casting molds and flasks could take several weeks. Moreover, a lot of materials was required to make the master casts.
Sand 3D printing takes place in a matter of hours and does not require large investments.
3D printing allows you to obtain prints that exactly correspond to the digital model. The quality of the prints is practically independent of the human factor.
Seamlessness and surface quality
3D sand forms do not need to be split. Therefore, the molds are fabricated from full target parts. As a result, the molds are lighter since there is no fixing no reinforcing elements required. On the same note, there is less post-processing of the final part, because there are no seam marks on the models.
Complexity of printable designs
3D printing with sand, in which the material surrounding the model serves as a support, allows you to print complex injection molds of any geometry. From the 3D printed casts, you can create parts that cannot be produced using traditional casting methods.
The material that was not used in the model, which served as a support during printing, can be reused after removing the printed part.
Examples of 3D Printing with Sand
Examples of 3D sand printing of injection molds printed using the Binder Jet technology.
Sand 3D Printing Equipment
The 3D printer for sand printing FHZL PCM1500 creates sand models of injection molds with an accuracy of ± 0.3 mm and a layer thickness of 200 microns. The unit has a print volume of 1500 x 1000 x 700 millimeters.
The FHZL PCM2200 3D printer has a print volume of 2200 x 1000 x 800 mm. The unit can print with quartz sand, calcined, as well as synthetic and composite materials. It’s layer thickness – from 200 microns.
ExOne S-Max Pro
ExOne S-Max Pro prints prototypes and molds from sand with a layer thickness of 260 microns. This unit has a print chamber measuring 1800 x 1000 x 700 mm. The unit also has two chambers, each with a capacity of 1260 liters, that automatically replace each other.
The ExOne S-Print 3D printer has a 800 x 500 x 400 mm printing chamber. This unit prints with a layer thickness of 240 microns.