In response to our customers’ wishes, we perform surface finishing of parts to ensure the required surface quality.
Our finishing services include:
- hand grinding
- vibratory finishing
Hand grinding is mainly used on SLA printed parts. Removing the remains of support structures is part of the standard post-processing approach. If the customer requires a high-quality surface finish, the parts can be additionally ground to remove any traces of building layers.
Sandblasting is part of the standard post-processing of SLS and SLA printed parts.
In SLS parts sandblasting is actually part of the standard cleaning procedure. The method removes any unsintered powder sticking to the surface. In SLA parts sandblasting is used to ensure a uniform surface finish.
Vibratory finishing is suitable for SLS parts, because it produces a smoother surface texture. The workpieces are placed into the tub of a vibratory tumbler where they vibrate together with the polishing or grinding media. The media rub against the printed parts, polishing (smoothing) the surface of the parts. The finishing process depends on the type of the polishing or grinding media, the vibratory frequency and time of processing.
There are two vibratory finishing methods: vibratory polishing and vibratory grinding.
Vibratory polishing of surfaces utilizes non-abrasive tumbling media. Using this procedure, surface polishing does not include any removal of material and the overall geometry is not altered. Also, there are no deformations of the parts’ edges. After the polishing, layer lines are still visible but the transition between them is smooth. In SLS printed parts, vibratory polishing reduces the characteristic surface roughness.
Vibratory grinding is aimed at achieving a smooth surface finish. In SLS parts the process reduces or completely removes the traces of manufacturing, leaving the edges rounded. The grinding media used are abrasive, which causes a partial erosion of the surface of parts. The material removal rate is approximately 0.03–0.08 mm. The rounding of the edges depends on the exposure of the edge and the thickness of the wall.
Printed parts that include thin or breakable elements (plugs, tongues, thin walls) are not suitable for vibratory finishing because there is a risk of breakage or bending.