The question of when will more engineers use 3D printers may be answered this way—when the price per prototype drops, some say to as far down as less than $1.00 a part. At least that’s what Ezra Zygmuntowicz, CEO, founder, and “hacker” (his words) at Trinity Labs thinks. I met Ezra at the recent MD&M West show in Anaheim, CA. He was displaying his new prosumer 3D printer in the PBC Linear booth. Why there? Because PBC Linear is the supplier of the lead screw rails for the axes and carriage of the Aluminatus TrinityOne 3D printer.
The hobbyist and engineer alike are eager for low-cost, kit style 3D printers that accurately and repeatably deliver 3D printed parts. But as users are discovering, it’s not quite as easy or simple for vendors to deliver such a 3D printer. One of the keys to quality, robust 3D printers is the components used to deliver motion.
The Aluminatus TrinityOne, is an open source design. Not only is Ezra a proponent of open source technology and committed to providing designs for this community, he had interesting insights into the prosumer 3D printing industry and engineering needs.
But first, a bit about the Aluminatus. This printer uses the SIMO Series lead screw driven rails on the X and Y axes and Constant Force Technology (CFT) lead screw and nut to drive the carriage, from PBC Linear. The 3D printer delivers linear motion with a repeatability of ± 0.02 mm/m and a layer height of 50 microns. The parts produced on this printer show a very small stair-step effect. The CFT lead screw allows the drive mechanism to accelerate, brake, and corner fast and precisely.
Many 3D printers in this price range use belt drive technology. Depending on the printer, belts will hold repeatability to ±0.1 mm/m and layer height to about 100 microns. Belt technology, though, can result in “springy” motion, which can create parts with moray patterns and a loss of sharpness in holes, cavities, or other object features. So the use of machined components delivers better quality 3D printed parts.
Use of rails and lead screws in the Aluminatus also means this printer is made of fewer components than many 3D printers in this class—35 parts versus several hundred in other units. It takes about 2 hours to assemble. Another benefit is the lead screws let users use the entire 300 X 300 X 350 mm workspace.
In his design, Ezra wanted a simple, easy to build printer, so he chose to work with a company experienced with motion and motion control. Noted Ezra, PBC Linear offers a range of axes, actuators, lead screws and other components, at an affordable price, that fit together in the kit style he wanted, and that take the work out of assuring his printer delivers good resolution and accuracy.
Ezra and I spoke about a number of things, but one of the more interesting comments he made involved materials. While he believes the prosumer market is the way to go, he noted that for engineers to unhesitatingly use any model of 3D printer, the material cost of prototyping a part must be about $0.30 per part. Today’s 3D printers, of any class, don’t quite deliver that price point. But this is what he sees as necessary. He went on to note that engineers won’t readily spend $50 to print a part. (Some material cassettes cost $50, and if you build one part with that much material, a definite possibility, it becomes an expensive prototype.) Ezra sees little reason for the price of materials to be high, and is developing his own materials for the Aluminatus. This printer currently works with PLA and ABS in multiple colors. As Ezra noted, all the Pantone colors.