3D Printing


So what is a 3D printer anyway?  To be honest, it is a concept that is a bit difficult to explain.  When first described, it almost sounds like a magical, Star Trek like device.  You can download a file of any three dimensional object or design one yourself and hit print and the object appears in front of you.  3D printing isn't exactly a new concept.  It has been around for some time, but has usually involved a machine that costs hundreds of thousands of dollars or more.  Within the last few years, there as been a growing interest in 3D printing by the hobbiest and DIYers crowd.  For somewhere less than $1,000 you can buy either a kit or more commonly a pre-assembled 3D printer.  These lower cost models are almost all extrusion based (also known as fused deposition method) printers that use a material such as ABS plastic that is heated in a nozzle and precisely extruded and deposited.  The deposition starts on a platform and slowly builds material up on that platform to create the desired 3D shape.  Think of it as an automated hot glue gun that puts the "glue" (plastic) into your desired shape.

220px-FDM by Zureks
Figure 1 - Example of the "fused deposition modeling" approach.  1 - nozzle ejecting molten plastic, 2 - deposited material (modeled part), 3 - controlled movable table

Figure 1 shows a cartoon of how the layers are built up.  Figure 2 shows a DIY style 3D printer.  The system is controlled from the readily available and open source Arduino and associated shields and ramps.  Furthermore, there are several different open source firmwares that are commonly used in the hobbiest versions.  

Figure 2 - Prusa Mendel.  Similar to the type of printer I have used.  Stepper motors move the bed in two directions, two stepper motors move the extruder head vertically, and a 5th stepper forces the plastic through the heated nozzle.  The bed is heated to achieve better adhesion of the first layer.  

So you say, "These look like cool little toys, but why would I really need one?"  It only takes a little bit of imagination to realize that these devices could be a big game changer.  Now, instead of going to your favorite online store and having to wait for a new toy to be shipped, you can just download a design file and print it out at home -- never leave your house or wait for a box in the mail.  Or perhaps that little plastic bracket on your vacuum just broke.  No problem, whip out your 3D scanner (a topic for another post), scan in the broken part and you're back in business.  

The applications in the commercial world are even more drastic.  Say you are an auto parts store and your customers demand same day service so you are forced to keep a huge stock of parts.  With a 3D printer, you could conceivable keep no parts in stock -- when someone needs a part, they just print it out.  In the engineering and design world, it has always been commonplace to make models to aid in the design process, sales, etc.  Those models have typically been expensive and time consuming.  With the proliferation of 3D printing, it becomes that much easier.

Granted, I think we are a ways off from the world I'm painting.  What will it take to get to there?  The analogy to desktop printers is somewhat useful.  One of the things that make desktop printers extremely common is the ease in creating content.  Right now, it is not simple to create 3D models.  There are several online repositories of existing 3D models such as Thingaverse, Google's 3D Warehouse, and AutoDesk's 123D Gallery, but in addition to printing out someone else's content, it must get easier to create one's own content.  We need the equivalent of Microsoft Word for 3D structures.  There are some promissing developments here -- software packages such as Google Sketch Up and Autodesk's 123D.  If the content creation gets easier, I could also see more "printing services."  A number of these printing services already exist, however, the cost of printing can be several hundred dollars -- it only takes a few prints and you could have purchased your own printer.