| 3D modelling and it's corporate big brother of Solid | | | | developed by 3D Systems where a laser strikes a |
| Freeform Fabrication or Rapid Prototyping began in the | | | | bed of metal or plastic powder, fusing portions of it into |
| early 80's as a way to use machines to make objects | | | | the required shape. The bed is lowered, more powder |
| faster than a traditional modeler could. By using | | | | added, and the laser passes over it again. This |
| Computer Aided Design machines such as pen | | | | process, which is the original basis of the LENS |
| plotters and then variable-height plotters, developers | | | | process, can be used to create both fully solid or |
| soon came up with the means to have a machine able | | | | partially solid metallic or polymer objects in a limited run |
| to carve elements out of foam or wood in multiple | | | | environment.Stereo Lithography uses a laser striking a |
| layers or levels, but it was still one half or one side. A | | | | pool of photopolymer in a pattern defined by the CAD |
| CAD table could produce an object of up to 48"x48" | | | | or STL file data. Once the laser has finished it's pass, |
| with a depth of up to 4" - but only 1 sided, so two of | | | | the platform lowers, immersing the object under the |
| them would have to be made for an 8" object, or | | | | surface of the photopolymer and the laser passes |
| many layers for a more detailed or larger object.The | | | | over again, slowly building up an object under the |
| first Stereo-Lithography system was believed to have | | | | polymer. BaE uses Stereolithography to produce |
| been developed at Xerox labs in the mid 1980's by a | | | | prototypes of equipment and parts extensively.These |
| team of engineers who were experimenting with a | | | | methods have a very fine accuracy, ranging from |
| way to fuse toner into a more solid substrate. They | | | | 0.01mm for laminated Object Modelling down to |
| realised that by using a platform that moved only on | | | | 0.003mm for Stereolithography. This enables models |
| the z axis or up and down with a scanning laser that | | | | and objects to be made to exacting specifications and |
| could traverse across the entire plate on the x- and y- | | | | allows for items such as jewellery mounts to be |
| axis they could harden a layer of waxy toner, then | | | | designed and then mass-produced in days rather than |
| drop the platform down a tiny fraction, put new toner | | | | weeks.For larger objects such as columns, airplane |
| on, and do the process again, thus they could slowly | | | | components, car body panels, statues and the like - a |
| build up a form in 3 dimensions.Xerox was pretty | | | | different method can be employed. 3D routers or |
| creative in the 70's and 80's - In 1971, a team from | | | | cutting machines have also been developed that have |
| Xerox came up with the idea of putting a printhead | | | | a cutting or routing blade set on a movable head that |
| assembly and scanning laser into a photocopier and | | | | can travel on all 3 axes and do very complex carving |
| created the first laser printer. | | | | down to a resolution of around 0.1mm detail, depending |
| So, realising that this solid manufacturing process could | | | | on the cutting or routing heads.The markets for Rapid |
| be commercialised, they let the word out to | | | | Prototyping and Rapid Manufacturing for hobbyists is |
| manufacturers and developers who could put the idea | | | | growing. The machinery ranges in price from $3,500 up |
| to good use.In 1988, a team led by S. Scott Crump | | | | to over $500,000 for some of the metal synthesis |
| developed a process called Fused Deposition | | | | equipment. This enables hobbyists and people who |
| Modelling. They went on to form the company | | | | need limited run products to get them at a fraction of |
| Stratasys and produced Rapid Prototyping machines | | | | the cost of previous methods such as moulded casting |
| that used this technology to create physical objects | | | | or milling and engraving prototyping.Just do a search |
| from 3d models.Laminated Object Manufacturing or | | | | for Rapid Prototyping or Solid Freeform Fabrication - |
| LOM is a process developed and commercialized by | | | | there are plenty of companies out here ready to build |
| Heliosys, in which many layers of laminated paper are | | | | your 3d object in 3 full dimensions so you can hold it in |
| sealed together after they have been cut into shape, | | | | your hand.Tim Morrison is a founding member of is a |
| creating a 3d object consisting of thousands or tens of | | | | technology company developed to bridge the gap |
| thousands of sheets tightly bonded together.Laser | | | | between virtual and real worlds in the realm of 3d. Our |
| Engineered Net Shaping or LENS is a recent process | | | | goal is to be able to produce a 3d image on the |
| developed by Sandia Labs where a laser is focussed | | | | computer and then produce it as a physical object - no |
| onto a steady stream of metal particles sprayed into a | | | | matter what the complexity or detail involved. In this |
| pool of liquid metal. This process builds up a fully | | | | vein, we keep track of anything in relation to 3D |
| realised object with no hollow portions or any gaps. | | | | imagery that can bring our goals closer, be it gaming |
| The metal is fully dense and the final part is almost as | | | | consoles that can do more than play games, |
| strong as a milled item. Optomec has licensed the | | | | hardware imaginng solutions, and software that can |
| LENS technology into a Rapid Prototyping | | | | make our lives easier. |
| machine.Selective Laser Sintering or SLS is a process | | | | |