Get Ready to 3D Print your CAD File

Find below step-by-step instructions for converting various CAD file formats to STL for printing on Objet 3D printers.

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The CAD to STL Process


After designing a model in a CAD program, you save the design as an STL file. (Most CAD programs have this function.) An STL file renders surfaces in the CAD design as a mesh of triangles. The number and size of the triangles determine how accurately curved surfaces are printed. You control the number and size of the triangles by setting the following parameters when you create the STL file from the CAD design:

Chordal Tolerance / Deviation

The maximum distance between the surface of the original design and the tessellated surface of the STL triangle.

Angle Control

The angular deviation allowed between adjacent triangles. This setting enables you to increase tessellation, necessary for surfaces with small radii. (The smaller the radii, the more triangles are needed).

STL File Format

You usually have the option to save STL files in either binary or ASCII format. Binary files are smaller (by a factor of 6!), so this format is usually preferred. However, ASCII files can be visually read and checked.

STL Geometry Check

Model designs containing holes and gaps adversely affect the quality of the printed model. Therefore, you should perform a geometry check of the STL files before continuing. Thirdparty software for this purpose attempts to fix the geometry of problematic files.

Preparing Parts for Printing

Objet StudioTM contains a full range of tools for preparing parts for printing. You can scale models and arrange them on a virtual build tray for printing, and you can save the build tray as a single file, enabling you to quickly reprint a job.

The following pages describe, in detail, how your CAD software fits into the workflow for printing models with Objet 3D Printers.

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