This week’s selection is “Design for Additive Manufacturing” by Martin Leary.
Additive manufacturing is the future, but only if one properly designs printable objects that truly leverage the advantages of additive processes. That’s a huge barrier to the progress of the technology that has yet to be overcome.
3D Printing Without DfAM
Early on AM was used only for prototyping, as the materials were not sufficiently robust for end-use parts. Additionally, the surface quality was never close to the smooth surfaces one would see on an injection molded part.
That’s one reason why AM was not used for production, but there’s another: designers of the day would simply re-use their existing designs and 3D print them. They found, correctly, that the AM processes were slower, more expensive and often did not result in a part of the same or better quality. There was a lot of “why bother?”
The problem was that these folks were unconsciously attempting to apply a design targeted at other making processes for a new making process. It just doesn’t fit.
That sounds dire, but the truth of AM is a bit more subtle, and that’s really what this book is all about.
Economics of DfAM
Leary begins the book by spending a considerable amount of pages explaining the economics of 3D printing. Like any process, AM has its own unique economic environment, and it is within this economic space that AM designs can truly flourish. But you can’t flourish unless you actually understand the economics.
Leary clearly explains the difference between “classical engineering economics” and “additive manufacturing economics”, a fundamental piece of knowledge that anyone in the space must understand. With that understanding, Leary then explains the economically optimal scenarios for use of AM, and other economic aspects.
With that knowledge, Leary then goes on to explain exactly how to properly design parts for production on AM systems. This process, now known as “Design for Additive Manufacturing”, or “DfAM”, is slowly becoming more popular, as those who deeply understand it can then use AM optimally.
Leary explains the workflows necessary to achieve DfAM, as well as a series of DfAM strategies and their implications on design.
DfAM Technical Knowledge
The technical bits of DfAM are also discussed. First, Leary explores several key design technologies that enable the creation of complex designs, including lattices, topology optimization and generative design. I believe AM cannot truly grow without these critically important design tools.
Secondly, Leary explores the several AM printing processes to understand how his economic model and design strategies can map to the process. These include material extrusion, material jetting, vat polymerization, powder bed fusion, directed energy deposition and binder jetting.
Who is this book for? It’s for experienced designers and engineers who are contemplating entering the AM space, or those who have tried and were unsuccessful due to a lack of understanding of how best to perform DfAM.