Tuesday, May 15, 2012

3D Printing

One of the more interesting changes that technology is providing us right now is the promise of affordable home fabrication.  There are various technologies like laser cutters and CNC machines that are dropping in price dramatically, but perhaps most compelling is the 3D printer.  This magic little device allows you to turn the virtual into reality.  It can take a design from your computer and turn it into a physical object that you hold in your hand.  

Solidoodle 3D Printer

The implications of this technology are far reaching.  Imagine being able to fax a 3D part to someone much as we fax paper today.  Imagine companies providing plans for products or spare parts that you can print yourself.  My colleague, MIT professor Neil Gershenfeld, believes that taken to the extreme, this implies that some day the price of most everything will be based on weight.  Once you have the plans, the cost of the object will boil down to the cost of the material required to make it (weight).  It could certainly change the economics of distribution.  

At a previous job, I was lucky enough to have one of these printers that could make high quality plastic parts incredibly cheaply.  It was very compelling.  It works by heating then extruding high quality plastic out a small nozzle that is mounted to a "print head" that can move in the X and Y dimensions on a flat plane.  As that first layer begins to solidify, the mechanism moves up very slightly in the Z dimension to add another layer.  By building up layer upon layer, the entire object can be created.  One of the downsides to these devices is that the higher the resolution in the Z dimension, the slower the printing process goes because it increases the motion required of the print head by making more layers.  There are other technologies that work by spreading out a layer of special plastic "sand" and then using a laser in the print head to fuse together the plastic grains.  Then another layer of "sand" is laid down and the laser fuses together that next layer.  When the piece is done, The sand is poured out and what remains it the fused together grains that make up the object you were printing.  This can be faster than the extruding method, but still has a trade-off with Z dimension resolution.  This technique is not as refined, so there aren't very many of these printers available.    

One of the really exciting ideas is that you can recycle your objects locally.  If there was a shredder that allowed you to break appart the objects you printed and melt/form them back into the source material required for building, then you could build as many different things as you like just for the energy costs of printing and recycling.  Very cool.  


There are several manufacturers making printers now.  Prices start around $500 and go up from there.  Only a few years ago similar functionality would have cost upwards of $100,000. 

Makerbot Replicator
I expect to see many 3D printers at the Maker Faire this weekend.  If you are coming, you may want to check out Makerbot.  As you can see from the video below, they will be showing off some robots that they have printed up on their 3D printer.