Monday 4 April 2016

Colour 3D Printing

Colour matching in 3D printing is not quite the same as colour matching in traditional reprographics. Different materials reflect light differently and three dimensional forms create shadows producing variations in tone of colour that are not seen on flat images.

There are many factors that affect 3D printing in colour: reflectivity, translucency, surface texture, tonality and saturation are just some of them. 

As is often the case, it really depends what you are trying to achieve. The ability to produce skin tones or very light and washed out colours are often more desirable over fully saturated bright colours. 

At Lee 3D, we print using the ProJet 660 printer, made by 3D Systems, which prints CMYK coloured binder onto a white substrate powder. This offers a wide range of colour and tonal qualities. 


Sample parts made on ProJet 660
Gloss finish can intensify brighter colour


Parts made on ProJet 660
Light and subtle tones

While we have never claimed to match Pantone or RAL colours, we can get quite close as shown in the image below. 

The reality of these machines is that the whiteness of the powder varies slightly between machines and if printheads are not properly aligned and parts are not finished meticulously then they can produce inconsistent part quality. But by attending to details, it is possible to make high quality colour 3D prints using this system.


Matching colour to the RAL paint system
It is possible to get something pretty close with most colours

There are two main alternatives to the ProJet for colour printing. These are the MCor and Stratasys machines. The MCor machine has limitations on the geometry that can be produced, while the Stratasys offerings are significantly more expensive machines to buy and to run. In particular, it is usually not possible to print hollow parts on these machines as they need a solid platform of material supporting all parts of the model as it prints. A third colour printer looms in the background in the form of the HP offering, but this appears to print on a black substrate precluding pale and pastel shades. 

Of these, the newly released Stratasys J750 printer may prove to be the most accurate colour printer ever made. The parts are likely to be highly accurate and can have multiple material characteristics as well as colours. But lower cost and the achievable quality on a well made ProJet part may continue to make this the machine of choice for much colour work for years to come.


Colour 3D prints made on ProJet 660




For more information about Lee 3D colour printing visit http://www.lee3d.co.uk