Will the post-processing stage ever become obsolete?

There’s no doubt that streamlining and automation will be a fundamental part of additive manufacturing’s evolution, particularly as it moves from prototyping to production. Materials and technology are improving at an increasingly rapid pace, but successfully implementing these new tools within manufacturing workflows remains challenging. One constant pain point for many AM specialists is the post-processing stage, and the amount of time and effort it adds to project workflows.

For all 3D printing techniques, a certain amount of post-processing will inevitably be necessary to achieve a professional result. This ranges from purely practical measures, such as removing any support structures, to cosmetic ones, such as painting and finishing the part to achieve a particular visual effect. The time and effort involved can vary considerably. For example, support structures for parts printed using stereolithography can usually be simply clipped away with minimal fuss. On the other hand, removing supports from DMLS prints is far more time-consuming, and will require additional sanding to achieve a clean finish. While this may not be a major concern for one-off parts or prototypes, it can potentially make delivering the same parts in large volumes problematic.

But what if the post-processing stage could be eliminated altogether, with 3D printed parts emerging fully formed from the printing bed, ready for use straight away? It’s not as far fetched as it sounds.

There’s been a lot of interest in Rize’s new 3D printing technology — augmented polymer deposition — since it was announced last year. Promotional material claims that the technology will deliver quality comparable to injection moulding, with support structures that can simply be snapped off by hand, and integrated tools for adding colour (including text or images) during printing. It’s certainly an attractive concept, but as with any new technology, the proof will all be in the results. The printers have only just become commercially available, so it remains to be seen how successfully they will be incorporated into manufacturing workflows.

Rize aren’t the only company tackling the post-processing challenge. Printing in full colour is still in its early stages, but is slowly becoming increasingly sophisticated. At the same time, Dyemansion are focusing their efforts on automating the cleaning/finishing process for plastic prints, so large numbers of parts can be finished as efficiently as possible.

So what will all this mean for our industry in the long term? Well, there’s little doubt that further streamlining will be essential if AM is to establish itself as a production technology, but at the same time, we shouldn’t discount the potential benefits of a well-considered post-processing stage. We’ve already looked at the practical benefits offered by finishing or metal plating for printed parts, including enhanced mechanical strength, resistance to chemicals, and suitability for medical or food-based applications. We would argue that it would be most productive to tackling the post-processing challenging by differentiating between the routine elements that are purely practical in nature (i.e. removing supports), but offer no tangible benefits, and those that will enhance a part’s overall performance. Routine elements should be automated or eliminated wherever possible. If this can be achieved, we will see a shift in the way post-processing is viewed, from a tedious necessity to an opportunity to enhance performance and deliver greater value.

We predict that we will see more machines of the sort offered by Rize in the future, where post-processing steps are integrated into the printing process itself, freeing engineers of additional manual tasks and allowing them to focus their efforts elsewhere. The challenge then will be to ensure these machines are effectively integrated into production workflows, so the possibilities on offer can be fully realised.