A third file format to convert CAD data into useful 3D printing data has been introduced into the market. It will be interesting to see if this one succeeds any better than the AMF file format, which appears to be orphaned.

Why do we need another file format? Well, the .STL file format is (still) used by all 3D printing units and machines to slice CAD data appropriately for 3D printing. At the recent AMUG Conference, Chuck Hull, who is the father of .STL, commented that he was amazed it was still being used; the file format has been around for 25 years or so.

In 2011, ASTM/ISO developed and released the AMF file format, which was developed to take advantage of new features and functions in 3D printers that .STL could not, like color and much larger files.

However, AMF has not taken off for several reasons:

–Additive manufacturing vendors are waiting for enough customers to request the use of this format before they include it with .STL.

–CAD developers are waiting for enough customers to request the use of this format, although a few CAD programs do offer it.

–Users of additive manufacturing systems have not made enough noise about incorporating AMF and continue to use what they know, which is .STL.

Now, we have the 3MF Consortium, launched on April 30, 2015. This industry consortium will work to define a 3D printing format that will let you send full-fidelity 3D models to a number of other applications, platforms, services, and printers. The consortium’s goal is to “quickly release and then maintain a specification that allows companies to focus on innovation, rather than on basic interoperability issues.”

The initial version of this specification is available for download now at no charge. The technical working group is expecting to launch several new important additions to this standard before the end of this year.

Founding members of the 3MF Consortium are: Dassault Systèmes S.A.; FIT AG/netfabb GmbH; Microsoft Corporation; HP; Shapeways, Inc.; SLM Solutions Group AG; and Autodesk Inc.

Many in the media are focusing on Microsoft’s role, which was to contribute its 3D Manufacturing Format (3MF) to the consortium.

Similar to the AMF format, 3MF is an XML-based data format. The code will be open source. The Microsoft donated code reads STL/OBJ/3MF, writes 3MF, and can use Web Services for model repair. The source code will be on Github and cross-platform code is in development.

The 3MF format is designed to be an additive manufacturing format, with the complete model information contained within a single archive: mesh, textures, materials, colors and print ticket. Transforms and object references are supported, with multiple objects contained within the single archive. Single objects can be referenced or moved without changing the mesh, and multiple identical objects can be placed referencing the same mesh.

Noted Adrian Lannin, executive director, 3MF Consortium, “3MF will align CAD software and 3D printing hardware and software in a more information-rich file format, specifically designed to support the needs of modern 3D printing throughout the entire printing process.”

It will be interesting to see if this file format manages to replace .STL. AMF struggled and apparently continues to, since some in the industry felt a need to develop a third file format between the CAD data and the 3D printer.

I like what Chuck Hull said at the AMUG Conference, which was why even have an intermediate format? You should be able to simply take your design data directly into an additive manufacturing system and process it.

I wonder when we might see that development?

Leslie Langnau
llangnau@wtwhmedia.com