Printing in new dimensions

Jeff Lang presents a rollerblade that was made using Tech’s 3D printer.






Steven Gethard came to studio one morning to find that his design for a platter had leapt off the page and into real life.

In just a few hours, the sophomore industrial design major’s design had gone from a two-dimensional idea to a three-dimensional model he held in his hands, all thanks to the technology of 3D printing and rapid prototyping.

“On a 3D printer, you can submit (a design), and overnight it can pop right out,” Gethard said.

3D printers, used by the College of Architecture and Urban Studies, as well as the College of Engineering, are machines that create 3D models from design data in a digital file. Complex plastic models can be made at a resolution of one one-hundredth of an inch in a matter of hours using the technology.

Although some 3D printers scan an object to begin the production process, the Dimension SST 1200es printer owned by the CAUS requires a model to be made in a computer-aided design program, such as SolidWorks or Rhino 3D.

Jeff Lang, the computing technology manager for the School of Architecture and Design, said the CAD model is exported to a file format that creates a mesh, which shows the model as a series of triangles.  

“It’s a mesh representation of all the surfaces and curves done as triangles,” Lang said. “The triangles are patched together to make smooth surfaces along the curves and the sides.”

The file is then analyzed by a software program called Catalyst, which plans tool paths for the two building heads in the printer. The software projects the amount of materials needed and the time the build will take. For example, a six-inch-by-half-inch-by-three inch model would take five hours and seven minutes to create.

The software also points out potential imperfections in the design.

“Maybe someone made a wall too thin and it’s going to collapse and not be the right strength — this is print preview taken to the extreme,” Lang said. 

The file is sent next door to the 3D printer, which is about the size of a refrigerator. The bottom of the machine houses spools of building material, ABS plastic and support material, which is made of water-soluble, rendered animal fat.  

3D printers work on the principle of additive manufacturing. Instead of physically removing excess material to produce a desired model, an additive process builds by adding material layer by layer. 

“If you were working in wood or metal, you start with a block and you cut away,” Lang said. “This is the opposite — it builds from nothing into what’s there.”

Inside the 10-inch-by-10-inch-by-12-inch build envelope, the materials are fed through the build tools. The ABS plastic is ejected out of one tool head in a liquid state and rapidly dries after being laid down.

After the first layer of plastic, the second tool head lays the support material down. The process continues layer by layer, with the heads rising and lowering as the 3D materials begin to take shape.

The building process depends on the design’s complexity and size. Models can be completed in a time frame ranging from a few hours to 48 hours — a rollerblade model with individual wheels, laces and buckles is an example of the latter.

After the model finishes printing, the water-soluble support material must be removed by being placed in a water bath. This step can take 12 to 24 hours, and hopefully represents the intended design.

“When you do something by hand using clay or wood, you get imperfections but this comes out exactly as it would be on your model,” Gethard said.

While the ability to make intricate models relatively quickly is useful, it is not cheap. The Dimension SST 1200es printer used by the CAUS cost $35,000 at its time of purchase more than six years ago. Although innovations in technology have occurred since then, this model is still priced at $32,900.

While 3D printing will save students time, it will not necessarily save their wallets. Utilizing the 3D printer incurs a base cost of $2.50 along with a cost of $4.60 per cubic inch of material.

Despite the costs, 3D printing has made the creation of models a simpler and quicker process. However, models are not the only uses of this emergent technology.

Continue Reading:
12 Next » 

A version of this article appeared in the Feb 17 issue of the Collegiate Times.

Leave a Reply

Your email address will not be published. Required fields are marked *