So, technically, I'm the Principal Design Engineer for the Terrapin Works Design Team, in the Rapid Prototyping Lab in the Technology Advancement Program building, under Engineering Information Technology at the University of Maryland, College Park. There are a lot of organizations involved, but basically, I'm the 3D printer guy from UMD. This is an explanation of what I do.
To start off, that's me in the picture above. The same picture can be found here, the TerrapinWorks website. TerrapinWorks (TW) is the organization/group/program/movement I work for. TW is part of Engineering Information Technology (EIT) here at UMD, and our goal is to be able to make pretty much anything, to give experience to our student designers and lab managers, and to lower the barrier to entry for design and prototyping services to the UMD community. TW is a network of labs, people, and equipment around campus with a wide range of manufacturing capabilities. My job is to manage our design team, try and fix things when they break, run tests and provide operational data on a bunch of different machines, train new lab managers, set up fancy equipment, and otherwise do things I'm generally unqualified for.
All this started when my dynamics teacher, Kevin Calabro, asked me to come by and check out some new 3D printers they had purchased for an intro to engineering design course. I had talked to him about 3D printing in the past, so he knew I was interested, and he knew I had purchased a 3D printer to work on some robotics projects. I went in and talked to them for a while, and apparently convinced them that there was enough boring stuff to learn about 3D printing that they didn't want to do it themselves, so I was brought on-board the EIT team by our executive director, Jim Zahniser. The first time I went in, I was locked in one of the labs with some broken printers and instructions to try to get them working again, which was the best first day I could ask for. Starting that day, my job was to compare a number of consumer grade 3D printers for use in the introductory engineering design course, ENES100. To that end, I 3D printed a lot of cool stuff on a lot of different printers (rough job, but someone's got to do it), and I developed a "3D Printing Torture Test," or "Obstacle Course" that was designed to test printers on all the things they don't do so well (pictured below).
This file tests overhangs, bridging, horizontal and vertical thin walls, zero-thickness tapers, retraction, layer constriction or thermal stability, dimensional accuracy, extrusion cooling, x and y positional consistency, and a number of other more general aspects that impact overall print quality and capabilities. This print can be used to test most extrusion based printers and see what they are capable of, for the purposes of improving print settings and general quality benchmarking, and it is also pretty handy for explaining the capabilities of a 3D printer to people who don't have much experience with the technology. One of the cool things about this particular file is that through the university, I have been able to print this file on a large number of printers, in relatively controlled settings, to compare their performance. We've tested the MakerBot Replicator 2, 2X, 5th Gen, and Z-18, the Ultimaker 2, CubeX Trio, Lulzbot Taz 4, the PrinterBot Simple Metal, the FlashForge Dreamer, the M3D Micro, the Wasp Delta Turbo 60100, the Fortus 400mc, (Carbon 3D CLIP printer coming soon!) and more. We've even printed a modified version (below) on a NanoScribe Photonic Professional GT that was about as wide across as a typical human hair (shout out to my buddy, Fadel Muci for this one, and for providing the PrinterBot).
So, after testing some consumer grade printers for ease of use/maintenance, reliability, print quality, etc., we ended up deciding that the Replicator 2 was the best fit for our purposes. Which leads nicely to the question, what are our purposes?
ENES100 is, as stated above, an entry-level engineering design course. Every engineer at the school (not just mechanical) takes this course, typically during their first year, which amounts to about 600 students a semester. For the first half of the semester, we teach them general principals and technical skills relating to CAD, 3D printing, mechanics/dynamics, computer science/coding (Arduino), and electronics, and discuss some other more generalized topics like ethics, design practices, time management, leadership, and so on. It's a lot to cram into half a semester, and we're continually trying to improve the process to make it more interesting and use the time effectively, while minimizing stress. Then, after an extremely cursory look at all these topics, we throw them directly into a large engineering design project. They have the second half of the semester to design and build an autonomous OSV, or over-sand vehicle (sand buggy) that is supposed to complete one of five missions within an arena we set up in the lab. This project can certainly be pretty crazy and hectic, and isn't always a positive experience, but it can be a great opportunity to learn in a very forgiving environment where you don't have to be fully successful in the project to do well in the class.
Where do the printers factor in? (Yeah, I know, I'm asking myself a lot of questions and it's weird. I'm bad at transitions, okay?) Well, we have 10 printers set up at any given time - five in each lab, which allows every team to have a dedicated printer during their class period. We also host overnight print hours for long prints where a TA will help them start a print in the evening, which they can pick up the following morning. The printers are modified somewhat, with custom machined glass and aluminum build plates to improve ease of use and reliability, overhead filament racks, tool mounts, and other such non-invasive alterations. During the first half of the semester, as part of their homework, the students watch a CAD video series made by my friend, Justin Albrecht, that teaches them how to design parts for a small 3D printed car (image below, sorry about the resolution) with a working drivetrain (the design of which was a 2 month project for me, after getting the printers in for the course). The videos go over not only the CAD tools needed to design the components, but Justin talks about the logic behind many aspects of the design, including tolerances, thin walls, overhangs, and other common 3D printing practices and limitations. Then, every week, one student from each team has to print one of the files they've created, and by the mid-way point in the semester, every team should have a working car. After that, we let them loose on the printers, and give them access to use the printers for their project. They become just another tool for them to use, not required, but available if needed. Many teams print wheels, gears, sensor mounts, structural members, and other parts of their OSVs, and some teams are very creative in their use of the printers.
The main reason we brought in these printers, and the primary effect we hope they are having is to strengthen the link between CAD and prototyping/manufacturing. Until now, CAD has always just been a "because I said so" and "trust me, you'll need this one day" kind of thing, but low-cost 3D printers have given it a functional purpose. Building a part, measuring it, and CADing it out because "you need to for the report" is very different from learning CAD as a useful design tool. We took survey data from before and after bringing in the printers to attempt to quantify the impact the printers had, and we saw some very promising results. If you're interested in reading more words (I'm amazed you made it this far, honestly. You MUST be bored by now.), feel free to check out this paper Justin and I wrote together, with help from Kevin Calabro for an ASEE conference. It has a bunch more info on the stuff we did for ENES100, and details on the survey results.
Moving forward, I'm still involved in the course, training new lab managers, maintaining the printers, and providing design consultations for the current students, but I've moved a bit more to the TerrapinWorks side of things, and the other labs around campus over time. One of the flashiest installations we have here at UMD is the MakerBot Innovation Center (MBIC), which is a room with 50 3D printers, where any student, of any major, can send in a file and have it printed for 10 cents a gram. We have more print hours than any other similar installation, and despite some mixed reviews stemming from our own difficulties setting up SOP for the machines as well as reliability issues with the printers themselves, the MBIC has changed a lot about the typical student experience in quite a few classes (Check out the MBIC link above for details, and a very markety video with Justin and I in it). My experience with the Innovation Center has been quite fun as well, and has given Justin and I several opportunities to visit MakerBot HQ, meet their staff, and learn a lot about the company and their products.
The truth is, I've always loved mechanical design work, and I've always loved making stuff, and what began as a brief foray into additive manufacturing led to an immediate love for the technology, and has dramatically changed my life for the better. As an undergraduate student, I've be privileged to work on some very cool projects with terrific people. I've loved every minute of it, and I only hope that the work I've done can help someone else find their own passion and take their own path in the same way that others here at UMD have helped me.
That leads nicely to (again, not great at transitions, kind of heavy handed on this one) the last thing I'd like to say, which is thanks. Thank you to Kevin Calabro for bringing me in on this, for all the help and guidance, and all the random design projects. Thank you to Jim Zahniser, for adding me to the team, trusting an undergraduate student with more responsibility than he could reasonably hope for, looking out for me, and putting up with my constant lack of time. Thank you to Justin Albrecht for being a terrific friend and coworker for all these years. Thank you to my parents for all the appropriately applied support and yelling that got me here, and thank you to Niki Parker for always being there for me through the hardest and best moments of my life. The past three years have provided me with the most incredible opportunities I've ever received, so thank you to everyone who has made them possible.