Finishing of 3D printed components

SLS 3D printing part colored yellow

Convincing component surfaces



Depending on the additive manufacturing technology, the surfaces of 3D printed components differ. This creates a slightly rough surface with the powder bed-based processes SLS and HP MJF . In the FDM process, the pressure layers and the individual travel paths of the pressure nozzle are clearly visible on the upper and lower sides. The surface quality of the untreated 3D printed objects is sufficient for many applications, but can be significantly optimized with a few and often very simple finishing steps.

Finishing options for 3D printed components



Just as the surface quality varies greatly due to the technology used, the reworking that can be carried out on a 3D printed component also differs. With powder-based processes, the components must be completely freed from superfluous powder. With FDM, support structures or platforms often have to be removed. Depending on the material, the surface quality can now be prepared using grinding processes. At FDM this is mostly done by hand, while SLS and MJF are slide ground. Further finishing steps range from dyeing and painting to chemical smoothing, but these processes are only available for powder-bed-based processes.

SLS parts different colors

Dyeing


For the dyeing process, textile dye is used, which penetrates the surface of the component during the dyeing process. The coloring process is very simple: the necessary color pigments are dissolved in a heated water bath and the components are then added. After a certain time, the parts have absorbed the paint and can be removed again. A short drying phase follows and the parts are ready for the next finishing step or for use.

Close-up black MJF part

Compaction blasting


The surface of the finished printed components is compacted by the compaction blasting. A high-quality blasting material is shot onto the surface, creating a slightly velvety and smooth surface. In contrast to the unsmoothed surface, this is less sensitive to scratching and rough. In combination with the dyeing process, it is our most popular finishing combination.

SLS postprocessed

Vibratory grinding (tumbling)


In vibratory grinding - also known as barrel finishing - the finished components are placed in a vibrating trough after powder removal, together with differently shaped whetstones. The vibrations generated in it cause stones and parts to move through. This creates even abrasion on the component, which in turn leads to a homogeneous, smooth surface. Sharp component edges are rounded with this process.

Painted 3D Printing Component Selective Laser Sintering

Painting


After thorough removal of any visible construction stages and subsequent priming, painting with two to three top coats can be implemented. High-quality surfaces on visible components are therefore no problem.

PA12 reflective surface

Dichtol infiltration


With a Dichtol infiltration, 3D printed components can be made pressure-tight. The part is immersed in a bath filled with sealing oil. The impregnation penetrates the open pores of the component and closes them reliably.

SLS component colored

Chemical smoothing


Using what is known as chemical smoothing, surfaces on 3D printed components can be refined in such a way that they come close to the surfaces of injection molded components. For this purpose, the part is hung in a closed apparatus in which the solvent is evaporated. This fine solvent vapor attacks the rough surface structure of the part, which smooths it and creates a uniform surface finish.

Not sure which finish is necessary for your application? - We are happy to help you!