New, Improved 3-D Printer Makes Objects at a Faster CLIP

An inverted model of the Eiffel Tower emerges from the resin pool of a 3-D printer that uses the Continuous Liquid Interface Production methodology, or CLIP, for printing monolithic objects continuously. Lars Sahl

3-D printers are useful in many industries, as well as in the home and in space, but one limitation many of them share is the necessity of printing objects in a series of layers rather than as one continuous surface. This can give a rough quality to objects, which must often be hand-finished. A new printing method, highlighted in a TED Talk Monday night by co-creator Joseph DeSimone, does away with that weakness, allowing for smooth, continuous surfaces — and it's far faster than current 3-D machines, to boot.

Existing stereolithography printers shine light on a bath of photosensitive resin from below, solidifying a layer of the printed object flush with the bottom of the container. The platform is then lifted a few fractions of a millimeter to allow liquid resin to fill in the space, and the next layer is printed. To watch, it looks like a magic trick: a foot-tall object being lifted out of an inch-deep tray of liquid.

The cheapest and most common 3-D printers lay down layers of thermoplastic one at a time, creating a stair-step effect. Other methods reduce this problem, but still print one layer at a time. Devin Coldewey / NBC News

The new method, called continuous liquid interface production (CLIP), is similar in that it exposes the resin from below, but the researchers found a way to create a "dead zone" at the bottom of the bath where the resin remains liquid. Now, instead of creating a layer and then lifting it up by a set amount, the platform is constantly moving up very slowly, and the image being shined on the light-sensitive resin is constantly changing to keep pace with that movement.

This creates an extremely smooth surface instead of a rough or jagged one, and while the process may look slow to our eyes, it's far faster than anything else out there. Formlabs' Form 1+ printer, which is perhaps the closest in principle to CLIP printing, creates objects at about 1-3 centimeters of height per hour. The CLIP method printed twice that in 10 minutes — roughly 10 times faster.

"Parts can be made with amazing properties very fast, often within tens of minutes versus hours," said DeSimone, a chemistry professor at University of North Carolina and founder of Carbon3D, in an email to NBC News.

3-D printing's sometimes rough results and interminable length have held it back from certain applications, but if CLIP is adopted, the much-hyped technology may find itself in the home and workplace, not just in heavy industry and design labs.

The paper, by researchers at Carbon3D, the University of North Carolina and North Carolina State University, appears in the March 16 issue of the journal Science.

3-D Printing Technology Helps Save Young Boy's Life 3:31


—Devin Coldewey