At Jawstec, we work with the Desktop Metal system. This integrated system of software and hardware provides bound metal printing all within our facility. It is a quick and seamless process that not only creates excellent quality products but also offers unique design possibilities.
This is called the Studio System. It uses a printing technique called bound metal deposition, or BMD. BMD works using metal rods held together by wax and polymer. These special rods are fed through an extruder and shaped into the final product layer by layer.
This unique 3D printing method is what this system is all about. The key lies in the wax and polymer binding. After the part is initially printed- what can be called a “green part”- it needs further processing for completion. First, the part is placed into the debinder. Here the part is immersed in a special proprietary debind fluid. This fluid dissolves the materials primary binder, leaving an open-pore channel structure. This creates a“brown part”.
The final step has the part placed in a furnace. It is heated almost to melting temperature, which removes any remaining binder and fuses metal particles together, sintering the layers. This is a key step as it ensures structural integrity and is one of the key considerations for designing parts to be printed using BMD. Part features, support structures, and build orientation must all be designed with this sintering step in mind. The end result is the finished part.
Of particular concern when it comes to BMD part design is the shrinkage that occurs during the third and final sintering phase. This means that the initial printed part will need to be slightly larger than the intended final part. Structural integrity in near-melting temperature is also something to think about for BMD printed part design. The wall thickness has to be thick enough to stand under its own weight during the sintering phase. Keep in mind as well that holes will be printed slightly undersize, which requires a slight increase of their size in the 3D computer model- though an alternative is to leave the holes as-is in the model and machine them to the appropriate specification as a part of post-processing. BMD does not lend itself to thin embossed or debossed features.
With overhangs of more than 40 degrees, BMD printed parts require supports. It’s here where the sintering phase very greatly affects the design. The printing process can manage much greater angles than sintering can, giving you a false sense of security until the finalized part collapses. It’s key to avoid cantilever masses as well as small features that will cause the entire part structure to sit on supports.
The debinding phase can also affect design. Tall, thin, unsupported features can be difficult to debind properly. Infill spacing and wall thickness also need to be adjusted to ensure quick debinding.
BMD solves many problems found with other metal 3D printing techniques. The supports are significantly easier to remove than with those other methods. It can manage design geometries that are not properly doable in metal 3D printing otherwise. It allows for designs that are not otherwise possible to 3D print in metal because it’s multi-phase process allows for the structures to be strengthened.
Because the materials used with BMD 3D-printing are metal powder held together by a binder upon initial printing, this means that many different kinds of metals can be used with this 3D printing technique. Copper is one metal in particular that BMD makes much more workable than normal with 3D printing, as other methods find it difficult to work with due to its thermal conductivity and laser absorption characteristics. With BMD, it is very easy to print as the primary method for solidifying the material layers is printing, binding, and sintering, not lasers or purely extrusion of molten material. This in fact allows for many possibilities for BMD-style of 3D printing as the technology continues to develop
What products are best for BMD 3D printing on the Desktop Metal system? Desktop Metal lends itself to custom optimization. If you are looking to reduce weight and/or material use, utilize unconventional angles and gaps, or just try something new with metal product design, then BMD is a good option for your product. As listed above, there are specific design best practices that go along with using the Studio System for BMD 3D printing, but they are relatively simple limitations to work with that actually will help reduce overall cost in material use.
The Desktop Metal Studio System allows for rapid progression through all phases of BMD 3D printing. The workflow from print to sintering is seamless. It is integrated via Desktop Metal’s own proprietary cloud software. Any product produced on this system will be converted from a digital file to a finished part in hours.
At Jawstec, we are proud to utilize a Desktop Metal Studio System for our BMD 3D printing. Our team provides industry-leading service every step of the way for 3D printing whether you are mass-producing parts or creating a custom object for a personal project. No matter what your project is, we will provide the same level of dedication that we have given to our work with BMW, Amazon, Apple, and many more. Try our 3D printing quote tool or contact us to see how we can help you use this amazing technology for your project today!