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66 MMS August 2017 mmsonline.com ADDITIVE INSIGHTS Understanding Industrial 3D Printing So are you ready to take the plunge into addi- tive manufacturing and start making complex, lightweight parts with incredible strength-to-weight ratios, or consolidated assemblies that minimize part count and provide superior functionality? Not so fast. AM is a lot harder than it might look, and diving into it headfirst can create more work and headache than benefit. I suggest easing your company into AM through "layered learning." Design aids. The early days of AM were all about 3D-printing design aids: prototypes, concept models and other visual examples that support product design and development. While many shops have moved on from this use of the technol- ogy, there are two key takeaways from using AM in this way: users become familiar with AM work- flow, and they start to realize the limitations of AM processes. The former is helpful because this workflow—CAD, creating STL files, determining build orientation, slicing, toolpath planning—is necessary for every level of additive manufactur- ing; the design tools and level of detail just get more sophisticated as one progresses into more advanced AM use. And insight into some of the limitations of AM, such as layer height, overhang angles, thin walls, part warping and more, will continue to be useful in the more advanced stages of AM, beyond 3D printing with polymers. Product ion aids. Designing and printing production aids—jigs, fixtures and tooling—is the next "layer" of AM learning. This may be one of the least interesting applications of the technol- ogy, but it is probably the quickest way for a shop to realize a positive return on its investment in any additive system. For instance, a small, desktop 3D printer can easily pay for itself in one to three months if it is used to 3D-print fixtures and jigs that save time, increase efficiency and avoid other costs. The workflow is the same as that required for printing design aides, but it further challenges the user to think more creatively, a critical step for successful transition to more advanced AM. Production aids will likely start out as direct replacements for existing jigs and fixtures, but eventually users will start designing more sophis- ticated and intricate tooling. Using AM for this purpose helps users build their confidence, get more comfortable working with the technology, and understand its pros and cons. Early successes will also help increase buy-in from others in the company, and it may even be a way for shops to start saving for larger, more expensive AM systems. For example, a portion of the efficiency gains and/ or cost savings could be directed to an AM "sav- ings account" to support system upgrades or new AM technology purchases. Part production. After users have mastered the workflow, gained insight into AM's process limitations and improved their creative confidence, they will be ready to start transitioning from poly- mer to metal AM systems and to shift into produc- ing end-use parts. As with the printing of produc- tion aids, this will likely start with substitution of additively made parts for parts made by conven- tional production methods, which will allow com- panies to make apples-to-apples comparisons between those parts. Users will quickly realize that post-processing AM parts (support removal, stress relief, heat treatment, hot isostatic pressing and finish machining, for example) will make them more costly to produce than the same parts with traditional manufacturing processes. At this point, Easing into AM A layered approach to learning the technology will help lessen the headaches. TIMOTHY W. SIMPSON PAUL MORROW PROFESSOR OF ENGINEERING DESIGN & MANUFACTURING PENNSYLVANIA STATE UNIVERSITY