A Better File Format for 3D Printing to Replace STL?
Phil Kinnane August 8, 2012
I have previously blogged about 3D printing and how it would be great if you could go from model to product in one step. Now it seems as though the Stereolithography (STL) file format is reaching its limits for being useful as a standard for this type of application. The printers themselves, and what they are capable of, are outstripping the abilities of the file formats to support their new capabilities. Moves are being made to develop a better file format for 3D printing, and the American Society for Testing and Materials (ASTM) is throwing its weight behind this.
Today, Design World broadcasted a podcast that discusses the new Additive Manufacturing File (AMF) format. One of the leading advocates for AMF from Cornell University, Hod Lipson, mentions in this podcast some of the deficiencies with STL. These include the fact that 3D printers can now print in multiple colors, but the STL format does not support this. For COMSOL models where colors are hugely important to express the variation in the physical property that is being simulated, I think it would be great to produce a 3D simulation that also includes colors.
Better in color?
Simulation of the electromagnetic field in a high-voltage generator
in an X-ray device. Model courtesy; Comet AG, Switzerland.
Other problems with STL include the fact that it does not support information for printing multiple materials simultaneously, although this is a feature now possible with 3D printers. And, as the machines become more and more accurate, they can print minute details and even objects with significant internal structures, such as a lattice. Yet, STL files do not scale very well, and file sizes are becoming enormous.
The AMF format supports these and other features. Further, the potential for adding even more properties to the file format, such as tolerances, is turning this into the manufacturing engineers’ dream. Yet, there is a chicken and egg problem, which the committee who is working with developing AMF is hoping will be sorted out very soon. Who will adopt it first, the CAD/CAE companies or the 3D printer companies? Once enough of them do, though, it should become a standard. I hope it happens soon.