Is the Traditional STL Format for 3D Printers About To Be Replaced?

The current format that 3D printers use is the STL file format (Standard Tesselation Language).

STL is also an abbreviation for (Standard Triangle Language), and it is also used by many people as abbreviation for (STereoLithography). Because the STL format is used by most CAD software, files that are produced in the STL format can be readily transported electronically between remote locations.

There is an abundance of free STL files on the web, so that the hobbyist or the tinkerer has no difficulty finding a variety of designs to print. For example, the following websites have repositories of free STL files: Thingiverse, Grabcad, Autodesk 123d, YouMagine, NASA, and many others.

Recently, Microsoft announced that it has formed a consortium with other companies to introduce a new 3D printing file format, to replace the STL format.

The purpose of this article is to raise and/or answer questions regarding the new proposed 3D printing file format. Specifically, it will be useful to know the following:

• Does the STL format have deficiencies that should be addressed?
• What new features will the new Microsoft format provide?
• Will there be concerns about using Microsoft’s 3D printing format?

Does the STL Format Have Deficiencies That Should Be Addressed?

The STL file format was introduced in 1988 and it has remained as the standard 3D printing file format. The format approximates the surfaces of a solid model with triangles; therefore many triangles are required to model complex surfaces. Obviously, an STL file can be quite large for a complex solid geometry, because many small triangles will be required to model the surfaces accurately.

As 3D printing technology became more sophisticated, it became necessary to add additional features to the STL format such as (a) improve the manner for modeling surfaces, (b) identify different colors, (c) identify different printing materials, and (d) define units.

The improved STL format, called the AMF (Additive Manufacturing File) format, mimicked the PDF (Portable Document Format) in many ways. Major features of the AMF format include the following:

• It is non-proprietary or open,
• It is XML based,
• It is backward compatible with STL,
• It can handle complex objects and fine details within an object,
• It supports lattices and constellations (multiple objects arranged in a constellation),
• It supports extra features such as meta-data (specialized information), formulas, printing information,
• It will be forward compatible with future format revisions.

What New Features Will the New Microsoft formats Provide?

Obviously, the AMF file format is addressing the major deficiencies of the original STL format, so why is Microsoft proposing another 3D printer file format?

At a recent developer conference, major features of the new proposed 3D printing file format were revealed, and they include the following:

• The file format should support information interchange throughout the entire 3D printing process, from CAD application to printer.
• The file format should contain a complete definition of the printed model, in a way that allows unambiguous and accurate processing of the model.
• The file format should be practical, simple to understand and easy to implement.
• The file format should be forward thinking, in the sense that it will be compatible with printing requirements of future generations that utilize more sophisticated 3D printers.
• The file format should address deficiencies of the STL format such as using many triangles to model surfaces accurately, inability to handle different printing materials, and inability to handle color and surface textures.
• The file format should be easy to use.

The proposal seems good, although it appears to be quite similar to the AMF format. If the newly proposed features are not significantly different from the AMF file format, it is reasonable to ask the question “Is this new format necessary?” Until further information is provided about the new format and how it will be implemented, it may be prudent to withhold criticisms and questions that cannot be answered at this time.

Will there be concerns about using Microsoft’s 3D printing format?

Several questions, concerns and criticisms have already arisen from the technical community about Microsoft’s proposed new 3D printing format. Some of the reasonable questions, concerns and criticisms are listed below.

• Is it really necessary for Microsoft to introduce a new format?
• Is it likely that the new format will be significantly better than the freely available AMF format?
• Is it likely that Microsoft will make the new format freely available to the 3D printing community? If not, will the 3D printing community be willing to pay for using the new format?

If history is a useful guide, it will not be surprising if the OSF (Open Software Foundation) or the GNU System comes up with a free version of the new format, in much the same way as Linux provides a free Operating System as an alternative to Windows and other commercial operating systems.

Conclusions

Microsoft’s idea of creating an improved 3D printer file format is a good one. However, it may be a good idea for the consortium to obtain useful input from CAD companies and the 3D printing community about whether to produce a freely available or a proprietary file format.

It is doubtful that the 3D printing community will readily embrace a proprietary file format and to pay for using it.

Because 3D printing has room to grow into a much more sophisticated technology, it may be premature to determine how Microsoft’s proposition for a new 3D printing format will work out.

Whatever the new format turns out to be, it will probably be richly featured, and it will have the flexibility to accommodate future advances in 3D printing technology.

Even though Microsoft’s new 3D printing format may be so richly featured that people will pay to use it, it should not take long before the OSF and/or GNU produce free versions of the new file format.

– IndiaCADworks