Rapid Prototyping
Metropolis Design is a comprehensive Rapid Prototyping service bureau. We offer a wide range of prototyping services in-house and have developed strategic partnerships to provide virtually any type of prototyping service your project demands. Our expert project directors will work with you to determine the best processes for your project.
Select the links below to learn more about the rapid prototyping methods we use in-house. If you would like additional information about these methods, or any other prototyping method, please contact us directly.
- SLA - Stereolithography
- Poly Jet - Eden 333
- RTV (Room-Temperature Vulcanizing) Molding
- Cast Urethane Parts
3D files and how we use them
Mainstream cad packages have the ability to save their native files as .STL, .IGS, or .STP files. When building rapid prototypes, Metropolis will convert whatever file type you send to us into a .STL file prior to making the part. This file type creates a 'facetized' version of the original solid file. All your beautifully contiguous blended surfaces are converted to triangular faces which are joined together at their edges to create an approximation of a curved surface. Therefore most designers and engineers like to see what they are getting before sending the file off to the rapid prototype machine. You can see exactly what the RP machine will build by saving the file as an STL. If you don't like what you see you can modify the smoothness of the triangulation of the file.
For example in SolidWorks, select the 'Save As' function in the File menu. Under 'File Type' choose '.STL'. Now click the options button. Two main variables are displayed on the right, 'Deviation' and 'Angular.' There are also two standard settings, 'Course' and 'Fine,' and a custom option. Click 'Preview' and you can see the file size change as you select various options or settings.
Once saved, you can view the file by re-opening the .STL version of the file, and while in the open file dialog box, use the 'Options' button to select 'Solid Model.' This will allow you to see the facets of the file and decide if it has enough or too much detail for your needs. Be aware, opening the solid model version of a .STL file can take several minutes.
As an example, at Metropolis for an average smooth part that will fit within a 10" cube, we use .002 deviation and 5 degrees angular deviation settings. On larger parts you may want to decrease the deviation setting to .005 or greater to help control file size.
These operations should be similar for other brands of CAD systems. Of course you can always send us the native file and we will save it out for you using our best judgment.
