Title
NPD 3-D Printing
Document Type
Student Presentation
Presentation Date
4-15-2013
Faculty Sponsor
Stephenn Tennyson
Abstract
My abstract is a little different, because I perform a technical service rather than do research on a project. I work in the NPD (New Product Development) lab here on BSU campus, under the direction of Blaise Lawless. My primary work is related the SLA (Stereo Lithography Apparatus) machine, which is our 3-D printer. I write up quotes for clients, create build platforms, and perform post-printing duties. The NPD lab on campus is a team made of Boise State professors, engineering students, and professional mechanical engineers. Their purpose is to help Idaho inventors, entrepreneurs, and manufacturers with product design, prototyping, and design for manufacturing needs. The lab has several pieces of equipment designed to further assist the team in achieving these goals, such as a CNC milling machine, the CUBE, and a SLA machine. When a client e-mails us requesting a quote on a project, or asks for a part to be built on the SLA machine, I write up a quote with the information. Once the build is given the go-ahead by the client, my job is to take the SolidWorks-generated parts and place them onto a build platform through a computer program called LightYear. This program places the parts on a ‘platform’ that the SLA machine can read. The importance of this step is because of how the SLA machine builds the parts. The SLA machine holds a vat of resin that contains the liquid, plastic-like material that the physical parts are made of. This resin can be transformed from a liquid state to a solid form by the exposure to UV (ultra-violet) rays. The machine uses a UV laser for this process. The physical parts made by this machine are built on a metal, perforated square about eleven inches by eleven inches and about the thickness of a dinner plate. This ‘plate’ is set on two metal arms, called the ‘elevator’, suspended above the vat filled with resin. The SLA then reads the program that I have set up in Lightyear and begins the building process. The physical parts are uniquely built. The metal plate is lowered into the resin, then raised. The UV laser begins to harden the resin left on the plate in an outline coming from the pattern that is read from the LightYear program. After this, the metal plate is lowered again into the resin, where it will be raised and the process is repeated. In this way, the physical part is built, layer by layer, until completion. Because the physical parts cannot be built directly onto the metal plate, supports are first built. These ‘supports’ are like stilts that the part can sit upon. This is done because after the part is built, it must be removed from the metal plate without damaging the physical part. The supports are built for this purpose; they are broken off to remove the part from the metal plate. Later, the remaining bits of supports are sanded off from the physical part. After the part is built from the SLA machine, it must be rinsed of excess resin. This is because the resin, when left in the liquid form, is sticky, messy, and toxic. Therefore, the part is placed in a vat of liquid called poly-flush. This liquid helps to separate the remaining liquid resin from the part. After the part is washed in the poly-flush, I hand-rinse each part in isopropyl alcohol in a further effort to remove all the excess resin. After this brief wash, each part is blown dry with an air hose, and set in a well-ventilated room to finish drying. Once each part is dry, I place the parts into a UV oven to complete the hardening, or ‘curing’, process. This is much like placing pottery into a kiln for finishing. Finally, the parts come out of the oven. At this point, I am able to use a light-grit sandpaper to get any remaining bits of supports off, as well as sand down any cosmetic blemishes that may have occurred during the build. After this step, the parts are finished, so I package the parts into a box. Later, the parts are mailed to the client.