If you design plastic parts you probably have a Design for Manufacturability (DFM) guide sitting on your desk. A typical list of things to consider when designing for plastic injection molding include:
•Radii
•Wall Uniformity
•Ribs
•Bosses
•Draft
•Snap-fits
•Screws
•Molded-in Threads
•Picture Framing
•Warpage
For each of the above bullets, you must alter your design to accommodate the limitations of injection molding tooling, (which is what “design for manufacturability” is all about). By the time the DFM rules are met, your original design may end up needing numerous adjustments, taking away from its intended use.
Talk about sucking the wind out of your creativity. Of course when you’re designing a product to be produced from plastic in the tens of thousands or more, your only choice for this volume is injection molding. But how many of you design products that will only be produced in the hundreds to a couple of thousand?
Using an additive manufacturing technology such as Fused Deposition Modeling (FDM) allows you to produce parts directly from digital CAD files. Because plastic parts are built in layers, you’re no longer confined to the constraints of DFM.
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Using direct digital manufacturing allows you the design freedom your product deserves. Imagine being able to optimize your design and product for its true end-use and not have to worry about how it's going to be manufactured.
Direct digital manufacturing with FDM could be the next industrial revolution because it offers companies an unprecedented freedom to innovate their products, processes and businesses.