10 Main CAD File Types You Should be Using
When thinking about CAD design, file formats are important. Any computer-generated document that is created must be saved as a file. This document contains all the details about the composition and how these need to be read, processed, and displayed. For instance, A Microsoft Word document or .docx file will provide details on the content and formatting. Similar principles apply to CAD design. Using software like AutoCAD or SolidWorks, you can produce digital documents. Then, this document is stored using a specified file format.
The 3D file format determines the program you can use to view the document. Additionally, it will also specify what is written in the document. This is the design itself for a CAD file. Any format can be created for CAD files by using digitalization services.
Regular CAD users are probably familiar with the associated file types, giving them more options when transmitting designs to coworkers and clients. We have compiled a list of the best file types for sharing both 3D and 2D CAD designs.
Properties of CAD File Store
1. Geometry Representation
CAD Geometry Representation: Image Source: researchgate.net
Meshes and B-Rep called polygonally and boundary representations, are the two methods used most frequently in CAD files to represent 3D data. A collection of exact geometrical and topological entities serve as the basis for the definition of B-Rep bodies. On the other hand, a mesh model is a B-twin Rep with all precise bounds replaced with a collection of approximations.
2. Topology
Only for B-Rep representations does topology play a role. Body types include solid, wireframe, sheet, and acorn shapes, as well as elements (shells, edges, faces, etc.).
3. Product Design
A product's structure comprises groupings of connected elements called assemblies and single objects arranged in a hierarchy called components.
4. Meta-Data
The meta-data in CAD files is an addition to the geometry, topography, and structure. Layers, Product and validation attributes, Manufacturing Information (PMI), object names and IDs, and user-defined properties are also included.
5. Visual Representation of Qualities
Additionally, CAD files can specify aesthetic characteristics, including colours, materials, line styles, textures, and light sources. Both B-Rep and mesh elements can have these properties applied.
10 Different Types of CAD Files
1. STL (.stl files)
A universal file format is the STL format. It is a format that 3D software specifically developed for storing 3D data. Using STL to express colour or textures is impossible because it is only concerned with surface geometry and forms. It is suitable for use in specific circumstances when complex CAD data is not required.
2. PDF (.pdf files)
Adobe's proprietary PDF (Portable Document Format) file format offers many applications. AutoCAD files can be created from PDF files. For simpler viewing, CAD files can also be exported as PDFs. A PDF file is appropriate if you just want to show off a 2D design to a client or someone who doesn't know anything about CAD. You can export your work to a PDF using many CAD tools.
3. X3D (.x3d files)
VRML is replaced with X3D as the default file format (.vrml files). X3D fills the gap left by VRML, which was widely used but only supported by a few software programs. In an XML format, 3D computer graphics are represented by the neutral file format known as X3D. Graphic scenes can be encoded using X3D and the XML syntax. Furthermore, it enables integration with a variety of APIs.
3. DXF (.dxf files)
Drawing eXchange Format, sometimes known as DXF, is a 2D file format utilized by AutoCAD's drafting and design services. Actually, it is the native proprietary file type for 2D representations in AutoCAD. This proprietary product is used by a variety of different systems and programs. As a result, it is most widely used as a universal file format for viewing 2D CAD documents. DXF remains the most popular file format.
4. ACIS-SAT (.sat, .sab files)
One of the two most popular native formats for the ACIS geometric modelling kernel is ACIS-SAT. Numerous CAE, CAD, CAM, and 3D animation platforms, mostly Autodesk programs, are powered by this kernel, opening up possibilities for the widespread use of ACIS-SAT. The format offers two extensions: SAB (Standard ACIS Binary), which is more compact and safe against round-off errors, and SAT (Standard ACIS Text), which is human-readable and allows manual adjustment of the model contents.
5. JT (.jt file)
JT is a common type of cooperation within the Siemens PLM environment. Its name is derived from the original name of its ancestor DirectModel toolkit. JT can contain a substantial number of components exported from different CAD systems because it was created to assist the display of complex assemblies.
Mesh data, which enables the loading of various LODs in accordance with the scale of the display, is the format's strong point.
6. VRML (.wrl, .wrz file)
The first 3D format explicitly designed to show 3D scenes on the web was VRML (Virtual Reality Modeling Language, formerly Virtual Reality Markup Language). In e-commerce, education, and collaborative creative projects, this format allows website visitors to interact with virtual things. While a plain text file is the most typical VRML format, a gzip-compressed extension is also available. VRML format is a common way to save objects and scenes in 3D modelling software.
7. Parasolid-XT (x_t, .x_b, .xmt_txt, .xmt_bin, .xmp_txt, .xmp_bin file)
Another persistent format that is a part of the modelling kernel is called Parasolid-XT. SolidWorks, Solid Edge, Ansys, OnShape, Siemens NX, and other modelling programs are built around an eponymous kernel. Similar to ACIS, the Parasolithed format has two essential file extensions: a text-based .x t extension (albeit less legible and editable than ACIS-SAT) and a binary-based .x b extension.
8. IGES (.igs, .iges file)
One of the earliest attempts to develop an interoperability specification between multiple CAD platforms is IGES (Initial Graphics Exchange Specification). Today, Autocad, Creo, CATIA, Siemens NX, and other CAD modelling tools support it, making it one of the most widely used neutral CAD formats.
9. STEP (.stp, .step file)
One of the most used CAD file formats is STEP. Together with ISO 10303, this format was developed. The specification for computer representations of product manufacturing data is ISO 10303.
Most current CAD programs support this file type. Single-file and assembly formats are both supported by STEP. A Bill of Materials may also be included.
10. DXF (.dxf file)
Autodesk developed the vector file format known as Drawing Interchange Format (DXF) as a means of data exchange across several CAD software programs. Since it is an open standard, almost all CAD software on the market supports it.
A variety of applications, such as Adobe Illustrator and Scan2CAD, can be used to read DXF files. DXFs are generally larger than DWGs, despite being smaller than their raster equivalents.
Conclusion
We hope you'll find this article informative and handy. The CAD application you use will determine the file format you select. Even though you might have to utilize a proprietary file format, you can export it as another file type. You should now have a solid understanding of the most common file types; this will help you learn more about CAD and widen your horizons.
If you are a 3D modeller, use the 3D modelling program that you are most familiar with, and make sure it is appropriate for the product you are creating. Aside from that, ensure the 3D models are exported in several file formats that work with your team's production software and equipment. If you want to prepare your 3D files for 3D printing, you can use SelfCAD's in-built 3D slicer to slice your designs and create G-Code that can be sent to a 3D printer.
Enjoy powerful modelling, rendering, and 3D printing tools without the steep learning curve.
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