From SLS Model to Finished Product in One Week
From zero to finished in one week
The production of finished products through freeform manufacturing is becoming increasingly common. Primarily, it involves plastic components, but there is also a significant demand for prototypes and small series of metal parts made of aluminum, magnesium, and zinc. A metal product cannot be "printed" in a regular SLA or SLS machine, so we engage specialized subcontractors for this purpose.
Starting with an SLS model
Let's take the example of the diode strip for the headlights of the Koenigsegg Agera, a complex product with high finishing requirements. The process begins with GTP producing a master of the diode strip for aluminum casting, which means creating a standard SLS model in polystyrene. The model is then sent to Formkon in Denmark, one of the leading companies in Scandinavia for producing metal parts from SLS models.
Casting in plaster
At Formkon, the SLS model is encased in plaster and placed in an oven. The "plaster package" is burned in the oven according to a specific temperature cycle, which both cures the plaster and melts/burns out the SLS model. The result is a plaster mold. With this method, we can cast objects that are completely impossible using traditional techniques, explains Lars Høy from Formkon.
Aluminum under vacuum
The plaster mold is placed under vacuum and filled with liquid aluminum. After cooling, the plaster mold is broken, leaving behind an aluminum detail identical to the original SLS master. The cast detail is cleaned of any plaster residues, and casting imperfections are removed. Once the post-processing is complete, the lighting components are delivered to Koenigsegg for further surface treatment and assembly into a new Agera.
"Koenigsegg, with its smaller series and high quality requirements, is a typical example where this production process is perfect," states Lars Høy from Formkon.
Complex details
"The advantage of this method, explains Lars, is that no tools are required, and we can cast highly complex details. All we need is a master from GTP, and we can then cast anything that GTP's SLS machines can produce, whether it's aluminum, magnesium, or zinc."
"As a standard practice, we also perform heat treatment to improve the mechanical properties of the metal. The entire process, with the contributions of Formkon and GTP, takes between one and two weeks."
