3D printing crystal-clear glass is no longer a pipe dream

14 Sep 2015

3D printed glass on show, via MIT

The rapid evolution of 3D printing continues unabated, with researchers finally developing a way to 3D print glass — transparent, strong glass.

3D printing is quickly becoming one of my favourite things. People are creating operational prosthetics, for kids in need of assistance.

There’s the team behind the BioPen, a handheld device to layer stem cells onto injured knees, healing wounds.

We’ve seen 3D-printing speeds explode with Terminator-inspired variants, shells created for injured turtles and even beaks created to help out toucans in distress.

A window into the soul of 3D printing

But what of glass? How can we print something that needs to be monumentally hot just to stay in liquid form, all the while ensuring it maintains its transparency?

Previous approaches included sintering, melding solid bits of glass together, but that’s neither ideal nor clear.

So step forward Neri Oxman and her team at MIT, which has just published its findings in Journal of 3D Printing and Additive Manufacturing.

The new, hot system retains the strength and transparency expected in glass, with CAD – as you would expect – the way to program and, ultimately, finish the product.

Feeling hot, hot, hot

Molten glass (1,900 degrees Fahrenheit) is loaded into a hopper in the top of the device after being gathered from a conventional glassblowing kiln, producing glass in a way described as “honey as it coils”.

3D printing glass

It seems the only human intervention required is cutting the finished piece away from the moving platform on which it is assembled.

“We can design and print components with variable thicknesses and complex inner features — unlike glassblowing, where the inner features reflect the outer shape,” Oxman explains.

For example, she adds, “We can control solar transmittance… Unlike a pressed or blown-glass part, which necessarily has a smooth internal surface, a printed part can have complex surface features on the inside as well as the outside, and such features could act as optical lenses.”

Gordon Hunt was a journalist with Silicon Republic