No, it's not printers that make things look like 3D on a 2D surface.

It is a printer that will build something based upon your drawing (think CAD).

I ran across this recently, and it looks pretty damn cool.  

Got an idea for a product?  Need to prototype it or build a mold for manufacturing.  Piece of cake with this.  

The prices are coming down and pretty soon people will be able to do this at home (within 10 years).

Anyone out there ever use one of these things?

Here is an example.

I have used their services regularly for new items being designed, but the units I have access to are well, well above consumer-grade.

Kharn

I've used one for a project with the University I attend. Well when I say "I" ,  I mean my project group and I.

SLA is pretty sweet, and there is an ongoing project to build self replicating rapid prototype machines.

http://reprap.org/wiki/Mendel

I have been debating on buying a kit, but it is hard to justify since I have free access to one a pro unit at work.

http://www.makerbot.com





This is a build-it-yourself 3D printer for $1300.  It looks pretty interesting, but I can't justify it to myself yet.




 
 
 
 

What does it "print" with?  Some sort of plastic resin?  I heard it lays it down in layers.

There are several varieties, to include resin (traditional whiteish, kind of translucent rapid prototyping you normally see), paper (each layer of paper is laser cut and the machine is set to make it in ~1cm blocks of unwanted material, so you break those away to get your model), sintered metal (very fun stuff) and plastic (can even do multiple colors, it uses four or more feed lines of whatever colors you want).

Kharn

Stereolithography

There are two ways to do rapid prototyping once is to "Print" layers of plastic to form a model.  this is traditionally down with the print head laying two or more types of plastic, one to build the part the other to support it while it is being made.    

The other uses liquid resin tanks that a laser traces the part in, as the laser passes through the resin it hardens it and builds  the part.  

We have one at work.  The thing is running constantly doing prototype work and making fixtures.  It has paid for itself many times over by not tying up our toolroom with excessive machining.

Objet Ours is like this.

Guy at work has one of these at home.  He's always bringing in little trinkets; Yoda heads, little airplanes, angels, various doo-dads generally smaller than a can of soda.

They look like they were built of one long peice of #5 mechanical pencil lead, if you could bend the lead around corners.  I guess the machine extrudes the plastic in a countinuous bead to form the 3D shape.  None of the items appears to be very strong, although for obvious reasons I haven't tried to break one.

Neat, I guess.  Useful for making Christmas ornaments?  I've yet to see anything of practical value, other than it seems to make him happy.

It looks like some of them are non-enclosed and can make larger objects.

This article talks about making a house with one.

Non-Enclosed 3D Printer Can Build Houses

 Kat Hannaford —  Normally they're contained in a box, so the fact that this 3D printer isn't confined means it's theoretically capable of building much larger objects that most. In fact, the owner wants to build a cathedral with it.

It lives in Pisa, Italy, and uses CAD software to create objects designed using the program. Blueprint Magazine describes how it works:

Driven by CAD software installed on a dust-covered computer terminal, the armature moves just millimetres above a pile of sand, expressing a magnesium-based solution from hundreds of nozzles on its lower side. It makes four passes. The layer dries and Enrico Dini recalibrates the armature frame. The system deposits the sand and then inorganic binding ink. The exercise is repeated. The millennia-long process of laying down sedimentary rock is accelerated into a day. A building emerges.

3D printers are still very expensive though, so before you start planning on adding a new extension or granny flat to your house you should definitely weigh up the costs. Having said that, 2010 is apparently going to see the cost lower drastically from the $15,000 or so that they normally cost, with the MakerBot being the cheapest we've seen so far, at $750. [Blueprint Magazine via MAKE]