3D printing at the micro level

Recently a couple of stories have surfaced about using 3D printing/additive manufacturing for parts that are microns in size. One of these companies is based in Israel. Now, a company out of Boston, Boston Micro Fabrication (BMF) has introduced a microscale 3D printer. I interviewed John Kawola, CEO of BMF to discuss this trend. Some of the key points he made during the interview follow.

 

“When it comes to additive manufacturing the next frontier of innovation isn’t big, it’s high precision, small parts,” said Kawola. “We’re seeing a convergence of major trends as the lines between additive manufacturing and miniaturization begin to dissolve. There’s no question that additive manufacturing starts to lose its appeal as parts get smaller. The challenges with precision and accuracy have stymied innovation for engineers and manufacturers looking to develop small, high-resolution parts.” But that’s beginning to change as researchers solve many of these challenges.

The idea of taking 3-D printing technology and gearing it toward doing small, high resolution, high precision, high accuracy parts began at MIT. Professor Mitch Fang has been with MIT for about 10 years and has been working with Digital Light Projection (DLP) technologies and high precision optics. He figured out a way to push 3D printing to a level that, at least today, is beyond the best of other DLP technologies. He founded BMF about three years ago. The first units went to customers in 2019. There are about 40 systems in the field, primarily in Asia.

–The opportunity for micro 3D printing is large. Markets include jewelry, small medical devices, electrical connectors, medical device filtration, and micro fluidics. Items that require very high precision. The manufacturing process to make such parts, whether it’s machining or molding, is typically more expensive than a standard injection mold. Many medical parts are injection molded, but the molds tend to be expensive, around $250,000 or more.

–With 3D printing, if you can save on the mold costs and save on the time, it’s a potentially big benefit. But with very small parts, there’s two things that are happening. One is the very high precision, very expensive, $250,000+ for molds in this market, which changes the math. And two, the contribution for materials in the final part is small because the part is small. “Even if there’s a big difference in material versus injection molding material cost,” says Kawola, “it matters much less with small parts.”

BMF offers seven of its own materials, but the company is open platform. The company is working with material developers DASF and DSM and others. The developed materials work on BMF’s new microArch 3D printer. Other materials will work on the printer as well.

Most DLP systems operate “bottom up.” The microArch operates top down. The light source is on the top. But in between the light source and the resin is a high precision optics system that delivers the high resolution. Then, the XYZ stage movement is precise. The combination of the optics and the movement and then software and materials enables the microArch to offer resolutions of two microns. So that means you can get accuracy in the 10 to 20 micron range. “You can do very precise holes that are, anywhere from 30 to 50 microns in diameter,” says Kawola. “And so that’s typically beyond the capability of the best polymer systems today.

–Other companies offer similar technology, such as nano 3D printing: There’s a German company called Nano Strive using a process called two photon lithography.

Markets: One is connectors, which is worth about $80 billion today. Then, there is the medical device market, which is similar in size, for end effectors for robotic surgery or tips for endoscope. And, high precision optics for electronics and sensors. That’s probably assessed for perhaps a $2 billion opportunity for small parts. Micro fluidics or a lab on a chip– that’s not an enormous market today, probably about three or $4 billion market. But with 3D printing– that could be a significant way that they make those in the future because making micro fluidic chips today is a challenge. If you take these markets and consider that a 5% stake in them is successful, the opportunities for micro 3D printed parts is somewhere in range of $5 million.