[alexhaefner]

I guess I'm not convinced. Can someone explain the utility of 3D printing beyond rapidly building prototypes? Can it really reach scale and quality to do mass manufacturing? And what types of products could not in any way be manufactured with 3D printers? Which could?

[pittsburgh]

3D printing isn't feasible for the the mass manufacturing of everything yet, but it's feasible for certain types of products today, and it is improving. Here are some ways in which 3D printing has moved closer in the last few years:

* Stronger materials, such as Somos NeXt resin: http://www.dsm.com/en_US/html/dsms/next.htm

* Cheaper materials

* BioCompatible materials, such as Med610 which just came out last week: http://www.objet.com/3D-Printing-Materials/Overview/Bio-Comp...

* The ability to print in more than one material at a time, as shown in these human feet: http://www.objetblog.com/2011/09/21/a-table-of-3d-printed-fe...

* Higher resolution printing, such as the Objet Eden500V which can print detail as small as 0.0006”: http://www.objet.com/3D-Printer/Objet_Eden500V/

Examples of consumer products currently being made with the help of 3D printers include:

* Invisalign braces: http://www.youtube.com/watch?v=EVQq9joOS_4

* Hearing aids: http://i.materialise.com/blog/entry/3d-printing-in-medicine-...

* Jewelry: http://www.summerized.com/jewelry/

Things will really take off for 3D printing when printers can simultaneously print in multiple materials like plastic, metal, and rubber, and in multiple colors per part. Until then, you're right that 3D printers will continue to be used primarily for rapid prototyping, but this will change within a few years as the technology continues to improve and the cost continues to fall.

[seclorum]

You forgot http://thingiverse.com/ .. spend an hour browsing that site and you'll see exactly why 3D printing is a concept whose time has definitely come.

[illumen]

Take those little 3d printers and then make it the side of a 4 story house. Now make it print using sand/glass/metal all in one pass. Now increase the resolution up to 5000dpi or so.

[tonye]

There is some research going on the UK (I can't remember the University now) to do with printing buildings. The potential for reducing raw material and labour costs must be huge.

[pittsburgh]

I believe you're thinking of this: http://www.youtube.com/watch?v=EfbhdZKPHro

Also related: http://inhabitat.com/3-d-printer-creates-entire-buildings-fr...