Binder Jetting (also known, variously, as “traditional inkjet and vinyl coating”) is a fast additive manufacturing process for creating objects defined by digital data like a CAD file defining the shape of a product or component. The physical output from Binder Jetting is a two-dimensional surface, usually with a rough texture, that can be engraved, embossed, printed, or even polished. Binder Jetting is based on the principle that the flow of a viscous substance, in the form of a jet of fluid, is controlled to produce a pattern of overlapping regions of varying thickness. This printing technology has grown increasingly popular in the manufacturing industry over the past few years, due largely to its effectiveness and ease of use.
Binder Jetting is ideal for use with both laser and inkjet printers because it provides consistent print quality, even under high load or high-speed conditions. In general, most printer applications used in the building industry can benefit from a Binder Jet system because it makes it easy to build parts quickly and easily from a wide variety of components. In addition, Binder Jetting reduces the total build volume of the print material from less than half to almost one-half when using its full-color Binder Jet method. This is important because as part sizes increase, so does the build time for printed parts. In fact, some production systems run only at full capacity when the part sizes are small enough to fit on a standard sheet of printer paper.
One of the primary benefits of binder jetting is its ability to create highly detailed, accurately carved metal parts because the technique combines a solid roller with an injector that is loaded into the roller during the printing process. The injector is loaded with pressurized air, which then forces the pattern of the metal into the injector port in the roller. The combined effect of the two processes – injecting the pattern into the injector at a high rate of speed and forcing the pattern into the metal – creates a domino effect of the constant pressure that creates the intricate details of the formed part. This process also provides a consistent, repeatable pattern for the part’s surface.
Another benefit of binder jetting is that it provides large sand casting cores in a fraction of the time possible with other mold techniques. Because binder jetting machines incorporate a solid brass or aluminum plate, the result is the production of full-color prototypes that are accurate to within microns. By incorporating solid molds with solid brass or aluminum plates, the capabilities of 3D printed metal parts become even more advanced and useful for functional designs and manufacturing applications. Many industrial 3D printed metal parts use binder jetting for their production capabilities because it enables them to form parts based on identical or near-identical specifications. This eliminates the need to design or test parts from scratch, reducing the time and effort spent on the final product.
Using a binder jetting machine coupled with an inkjet printer with integrated inkjet cartridges can be used to quickly prototype parts for a wide range of purposes. This includes precision engineering parts, precision surface designs, and rapid prototype tooling applications. In many cases, these parts can be used before they are complete, due to their accuracy, but because they are produced in many different colors and with a wide variety of patterns, they can also be used for color blending or final finishing. With the help of a computer-controlled software program, an artist can simply layer one color over another or overlay a pattern with various colors until he is satisfied with the final design.
The key to binder jetting is that the solid components can be applied to a solid binder or inkjet print bed through a series of steps. The first step is to place the metal parts on the binder jetting print bed, either manually or electronically. For most parts, this will involve placing them on the top of the print head or within an externally mounted enclosure that provides a stable base for the parts to rest on. The next step is to feed the solid material through a feeding plate into the binder jetting system where it is loaded with powder or ink droplets from a nearby printer or other system. The feed is usually a roller that applies the material to the part or its surrounding areas in a uniform manner.
The most traditional method of binder jetting is known as direct injection or additive manufacturing. In additive manufacturing, hot air or additive gasses are used instead of powder or ink droplets to apply parts, while the metal part is positioned underneath a roller. In some instances, direct injection machines may also use other types of additive media in order to provide a more polished, smoothed edge to the product.
In most cases, binder jetting is used with a solid brass or bronze enhancement. In other cases, ceramic tile materials may be used. The powder bed is typically made out of either steel or aluminum, although powdered resins are becoming widely used as well. When designing a part with a binder in mind, it is important to consider how the final product will be formed and whether it can tolerate the additional stress placed on it during the printing process. Most additive manufacturing processes and powder bed designs are fairly safe, but careful consideration should be taken at the design stage to ensure the best results possible.