Traditionally in additive manufacturing, polyamide or more commonly known as nylon has been white in nature for most of its powders. With the advent of the Multijet Fusion Technology by HP, most nylon prints have now been transformed into varying shades of gun-metal gray. This has been the main result of the proprietary technology involving binding agents to expedite the manufacturing process. For better or for worse, there is simply no telling. One can however note that this has indeed resulted in a significant challenge to add vibrant colours to the various printed parts.
While most additive manufacturers have taken to the typical methods of adding a coat of paint to give the additively manufactured parts some colours, that in itself poses a number of drawbacks. Paint scratches easily, and in certain cases, results in some scuffing. Paint cannot be applied for objects which are flexible in nature, which has been a huge advantage for the PA 12 prints that the MJF 4200 has presented. While powder coating can be applied to flexible parts, it would just seem fiscally irrational to do so.
As such, at 3D Metalforge, we have taken it upon ourselves to dye the various nylon components in a wide spectrum of colours. This has enabled us to meet a large number of client demands over the past year. Dyeing of nylon components can be a complicated affair. Too short a duration, and the colour does not sink in well. Too long, and it might result in patchy tones. As with everything in life, striking the right balance is quintessential. We have developed a system to be able to dye the various components in varying shades of colours. However, due to the nature of the base colour of the printed components, only darker shades of colours can be achieved. Certain exceptions can be made to bleach the components to achieve a slightly lighter shade nonetheless.
This presents an exciting challenge as HP will be rolling out their new suite of multicolor MJF printers. While the new MJF multicolour printers have shown to be rather promising with a wide array of vibrant colours, there will definitely be some key considerations. The cost factor might be the biggest hurdle with dyeing of nylon being a cheaper alternative. Without a doubt, the interest level in the new multicolour MJF printer is spiking and the community cannot wait to see what exciting opportunities it can open.