While visiting Chicago’s Museum of Science and Industry (an amazing place that’s entitled to a future post all its own) I saw a 3D Printer in operation. I’d previously read about the amazing things these printers can do and how they will radically change our lives in the not-to-distant future, but I had never been able to envision how exactly they worked. Seeing one in action solved that problem and indeed, the possibilities are infinite. Here’s how I now understand a 3D printer to work:
It looks like a large microwave oven standing on its side. Rather than have a circular rotating tray, it has a rectangular pallet sitting inside. The “print head” resembles a larger version of the print mechanism on an inkjet printer. If you’ve ever installed a replacement cartridge in an inkjet printer, you know that once you snap it into place, the “print head” motors back and forth across the width of the printer several times. I don’t know why it does that, but it’s the back and forth motion that I want you to envision. Instead of shooting a jet of ink onto a piece of paper, the 3D printer shoots a jet of quick-hardening liquified plastic onto the pallet. And rather than shooting the liquid through a pin-hole sized opening, the 3D “print head” shoots the plastic through a long, narrow slot. By passing back and forth over the pallet over and over again, each time depositing a thin layer of plastic on the appropriate spot, the printer slowly builds a plastic figure. If you’ve ever built a plastic model of a car, just picture the wheels slowly forming from the ground up, then the chassis, the fenders, the hood, the windshield and finally the roof.
The beauty of this device is that you design the object that’s to be built on your computer and then you build it. Just imagine the possibilities: If your door blows shut in the wind, create the perfectly sized door wedge. A handle breaks, fabricate a new one. As with all new technology, these devices are expensive but the price will go down and the availability will go up. Here in Lowell we should especially appreciate the historic context of this technology. American industry began with small, self-contained operations in or adjacent to households. Then, thanks to places like Lowell, manufacturing was centralized and massed to gain maximum efficiency. Now that model of manufacturing has died or at least moved away. With technology such as 3D printing, we’re on the cusp of a new industrial revolution that will give new meaning to the term “cottage industry” as every person with an imagination and a 3D printer can become a separate manufacturing facility.