THERE IS NO strict definition of a price below which a rapid prototyping or additive fabrication machine becomes a 3D printer. Some individuals include any machine that sells for below US$60,000, and others US$40,000. Considering that a large fraction of customers at present are in educational institutions, small companies or even single proprietorships and individuals, for whom price is of primary importance, we've decided to compile all the choices below about US$20,000. Here's what available today and its general qualities in the order of increasing price. To widen your choices beyond this, explore the commercial listings by technology. You can compare the specifications of the 3D printers listed on this page in our very complete chart.

RepRap RepRap is short for replicating rapid-prototyper, an open-source 3D printer design project initiated by Adrian Bowyer at the University of Bath (UK). RepRap uses robotic thermoplastic extrusion similar to fused deposition modeling at present, but ceramic, metal and other materials may also be possible at some point. The ultimate intent of the project is to eventually produce a machine which can make copies of itself. Parts kits and individual items are now available from these sources.

Bits From Bytes (UK) Sells complete kits of mechanical parts for about $600.

RepRap: Store US vendor selling mostly parts and sub-system kits.

Fab@Home An open-source project to design, develop and manufacture an inexpensive syringe-based additive fabrication machine and related software. The components to build the device can be had for as little as US$2,500, and a variety of materials can be used for building, from silicone to chocolate. The project is led from Cornell University, but there are participants from all over the world. A good choice for real pioneers and do-it-yourself fans who may be satisfied with parts and models that will not achieve a high level of precision, durability or speed of fabrication for some time to come.

Koba Industries The company provides kits for fab@home machines priced in the range of US$3,000. It also sells major machine structural part kits for those wishing to procure their own electronic and mechanical components or to experiment. An (almost) completely assembled version of the machine can be purchased for about US$3,600.

Desktop Factory The company is accepting reservations for an additive fabrication system which it will start delivering in 2008 with a price of less than US$5,000. The technology uses a scheme which transfers partially melted, 0.010 in thick, powder layers to the top of a build stack using a drum. Selective exposure is by halogen light source and the parts are said to be quite robust, although they may lack the finer detail and finishes available from other technologies.

Read an article about the machine...
News release about accepting reservations...
Learn about the company...

3D Systems See the company's separate web-site for the V-Flash^TM Desktop Modeler. This is a next-generation photopolymer-based technology which is said by 3D to have many of the characteristics of stereolithography, such as good finish and accuracy, but also limited material choices and properties. The technology builds an entire layer at a time and should also be relatively fast. The first machine based on the technology is now expected be introduced late in the first quarter of 2008 at a price of US$9,900. Versions of the machines have also been announced for dedicated rapid manufacturing applications such as hearing aids.

The company also sells Solido Ltd.'s LOM technology in the US under the InVision^TM LD brand name for about US$15,000. See below. Parts are produced fairly quickly and with surprising detail, although they may not have the functionality provided by other 3D printer technologies.

Read the V-Flash (TM) product introduction news release and see photos...
See a schematic of V-Flash (TM) technology...
Learn about the company...

Solido Ltd. (Israel) (Formerly Solidimension) The technology bonds layers of plastic film to form objects and is small enough to fit on a desk. The company's products are distributed in the US by 3D Systems. The system sells for about US$15,000 in the US. See above.

Learn about LOM technology...
Learn about Solido Ltd....

Dimension^TM This is a division of Stratasys dedicated to selling a low-cost 3D printer line based on the company's FDM technology. It's entry-level systems sell for about US$19,000. Parts produced have good material properties - probably the best of all 3D printer technologies - and can often be used in final applications, although they may lack fine detail and finishes.

Learn about the technology...
See photos and read about FDM part properties...
Read a news release about their entry-level machine...
Learn about the company...

Z Corporation The company offers the only commercially available color RP system, and also produces a low-cost machine in the US$20,000 range. Parts are not as functional as those produced by other technologies and they require infiltration before they can be handled without danger of breaking. They also have a sandy appearance and lack fine detail. On the other hand, the technology is considerably faster than any other and can give quick feedback and is useful for multiple design iterations.

Learn about the technology...
Learn about the company...