Scientists find way to edit 3D-printed objects after completion

29 Jan 2018

Image: science photo/Shutterstock

A team of engineers has found a way to edit 3D-printed objects after completion.

While 3D-printed objects promise a major revolution in manufacturing – particularly in future deep-space exploration – there is still one outstanding issue: you can’t make changes to it once the object has been printed.

But not any more, according to a team of researchers from MIT who have found a way of repeatedly changing the colours of 3D-printed objects after fabrication.

Called ColorFab, the method involves using a specially created 3D-printable ink that changes colour when exposed to UV light, meaning the object can be recoloured in a little over 20 minutes.

As the team improves upon this creation, they expect that this timeframe could shrink substantially.

Unlike previous attempts to change 3D-printed objects’ colours using single-colour systems, ColorFab developed a simple hardware/software workflow whereby the user uploads their model, picks their desired colour patterns and then prints their fully coloured object.

To change the colour, the method uses a UV light to change the pixels on an object from transparent to coloured, and a regular office projector to turn them from coloured to transparent.

The custom ink is made of a base dye, a photo-initiator and light-adaptable dyes. The light-adaptable or ‘photochromic’ dyes bring out the colour in the base dye, and the photo-initiator lets the base dye harden during 3D printing.

‘It’s a big step for 3D printing’

When the printed object is placed on the platform, it is then just a matter of choosing what colour you want to change it to.

Aside from trying to speed up the colouring process using a more powerful light or light-adaptable dye, the team hopes to make the colours appear less grainy. This could be achieved by activating colours closer together on an object, and so using blue and red to create purple, for example.

“This is the first 3D-printable photochromic system that has a complete printing and recolouring process that’s relatively easy for users,” said the paper’s co-author Parinya Punpongsanon.

“It’s a big step for 3D printing to be able to dynamically update the printed object after fabrication in a cost-effective manner.”

Commercially, the breakthrough could allow you to change the colour of your smartphone case depending on your mood, or for stores to show a customer what a product might look like in a different colour in real-time.

Colm Gorey was a senior journalist with Silicon Republic