When it comes to creating/programming parts for production, Computer Aided Design (CAD) systems have become a standard throughout the manufacturing industry. The software space is competitive and ever changing, with hundreds of different programs and applications available for professionals across the field.
Because of the wide variety, it became necessary to establish and adopt file formats that would function across various formats, so that an engineer using one software system wouldn’t have to question whether his design files could be used by programmers using another.
The two most widely used file formats for 3D CAD systems are IGES and STEP, but we are beginning to see one of those fall by the wayside.
History of IGES and STEP
IGES (pronounced eye-jess) stands for Initial Graphics Exchange Specification. This file format dates back to the mid-1970s and was created after the U.S. Government decided its contractors were wasting too much time and money converting shared data files to work across their various software systems. Upon the creation of the IGES format, engineers and other designer professionals were able to send and receive 3D CAD files and import part geometry on all major software systems. Today, IGES has become a standard across a wide range of fields, including military, automotive, aerospace and more.
The STEP file (Standard for the Exchange of Product Data.) was created by ISO (the International Standards Organization) in the 1980s to improve upon deficiencies in its predecessor (though it was not widely released until the mid ’90s.) STEP files contain more 3D data and part geometry than IGES, and have been proven to work across most major CAD programs. While IGES has more of a history and is still the leading industry standard, we are beginning to see a shift to the more versatile STEP format due to its expansive data offerings and ongoing upgrades.
IGES – Past Its Prime
IGES was the industry standard for a reason. When dealing with less complicated part design, this file format has proven reliable and can be imported by the widest range of CAD systems. IGES creates a surface translation of a particular file (as opposed to a solid model,) and this can work well for 2D components and in certain 3d applications, but it comes with inherent challenges.
Using IGES surfaces is a less versatile and more limited form of CAD. IGES files will include rudimentary part data (line, arcs, surfaces, etc.) but lacks the in-depth 3D/design information that can be critical for engineers and programmers (mass, volume, surface properties, dimensional tolerances and more.) They are harder to edit and manipulate, and IGES surface files are less dependable than their solid counterparts, often containing gaps or missing faces/entities. Because of this, IGES files often need to be repaired which creates added work for the end-user.
IGES, though widely used, has also become rather outdated.
IGES, though widely used, has also become rather outdated. The file standard has not received an upgrade in nearly two decades. In that time we have seen the introduction of new, more robust file formats that are subject to ongoing updates and improvements (STEP, Parasolid, and more).
STEP – The New Normal
The STEP file is quickly growing in popularity. It is one of the newer formats available and receives continuous updates to improve upon functionality across an increasing number of CAD systems. Though IGES has been around longer, the information-rich STEP file could very well take over as the leading industry standard.
STEP files contain all the same CAD information as IGES, as well as more robust 3D part data such as material properties, dimensional tolerances, and more. As opposed to a surface translations, STEP files rely on solid models which are more reliable and far easier to edit and don’t suffer from gaps or surface omissions. Solids are also used in a wider range of applications, from CNC machining and additive manufacturing to graphic design and marketing/advertising.
Due to the expansive data available in a STEP file, and its widespread adoption across industries, it is easy to see why this format is becoming a favorite of designers, engineers and manufacturing professionals. The STEP format is versatile, functional, and should remain a trusted 3D CAD option for years to come.