TreeHugger has been covering the 3D printer scene for a number of years, but it is getting very hard to keep up with the rapid rate of change, and the number of different models. Engadget does a post-CES roundup of 28 different models. Most of them work in much the same way, squirting out melted ABS or PLA plastic on an X-Y axis, sort of like a computerized etch-a-sketch mechanism, on top of a moving bed that gives the 3D Z axis. However other technologies are now showing up at the affordable end of the market:
A tray of liquid resin hardens when exposed to a laser, until the desired object is fully formed. The process is quieter than much of the competition and the resulting prints achieve a level of detail that blows away what we've seen even the most high-resolution consumer printers accomplish.
The PWDR printer uses a powder-based principle; an inkjet printer head squirts a binder onto white gypsum powder. The machine then spreads another layer of powder and the process repeats, building up thin layers into an object that you can't see until the whole thing is done and you pick it up out of the powder. According to Wired,
PWDR was developed by Alex Budding, a mechanical engineering student at the University of Twente in Singapore. “There were quite a few open source 3-D printers around, but a powder-based process was missing from the line,” says Budding. “And there was a specific application for the machine in the area of ceramic materials.”
It is all open source and you can build it yourself.
28 printers, three different technologies and more on the way; this is getting interesting.