3. OK, it looks like RP is appropriate. Now what?

If, after considering the geometry of the part or object you're trying to make and the limitations of RP, you conclude that rapid prototyping is the way to go, the next step is to obtain a three dimensional description of the item. This must be generated by a three dimensional CAD program, or from some other three dimensionally-capable software application. Most RP systems use the STL file format, but there's usually no problem obtaining that once a native CAD format, IGES, biomedical imaging or other common file type is available. The STL file has to be "water-tight," however. Otherwise the RP system won't know how to fill in the holes in the description. Thus, a certain amount of file repair may be necessary before the STL file can actually be built.

A wide array of repair tools, viewers, translators and other specialized software applications are available. If you don't have the necessary skills and tools to generate a file, many service bureaus can work from simple sketches. This is a less common approach today than in times past and can run in to money.

All I have to do is push a button, right?
Once the rapid prototyping machine has been fed the STL file to work with, the rapid prototyping system and its associated software will operate on that to translate the data into the appropriate slices, and perform machine operations using a set of parameters for the particular materials and machine settings utilized. Rapid prototyping systems often have complex parameters that require considerable knowledge to set properly. "Push to print" operation is an exception and not the rule for today's state-of-the-art. Operating a rapid prototyping system is still very much both an art and a science.