A Prototype is a Prototype is a Prototype - Not!

By Bruce Bradshaw, Objet Geometries

When you hear words like Kleenex, Q-Tip, and Xerox, do the actual branded products pop into your head or do you picture any facial tissue,  cotton swab, or photocopy? Now let me ask the same question about your 3D prototype model. When someone asks for an SLA part do they expect to receive the part that came off a stereolithography system or do they actually expect a part that best simulates the end product they are designing? My guess is they would expect and want the part that resembles the finished part.

  In many circles today, SLA has become the generic term for 3D physical prototypes. Many engineers and designers have fallen prey to this trap by not being as specific as they should be when requesting their prototype. As a result, they end up with a sub-par prototype for their design and get something that might not match the end product as designed.

  3D printing technologies and material choices available from manufacturers these days offer so much more versatility than SLA parts. The choices currently available facilitate greater design creativity and freedom,  and settling for an SLA part can limit and—in some cases—inhibit the design of a given product.

  Clearly there are many factors to consider when selecting the best materials for your design prototype. Whether the goal is to test the fit, form, and function of a design or to gain feedback from a focus group to better understand market acceptance, an SLA prototyped part might not meet your needs.

  If, for example, a prototype must simulate an over-molded design or would require varying elastomeric properties, an SLA part would require some additional postprocessing. This would add significant cost and time and is unlikely to result in a part that actually matches the end product. In another example, the end product might include a living hinge so the designer would expect a prototype that includes both a rigid section as well as the flexible hinge. An SLA prototype will not include the flexible hinge and it will have to be simulated with a clumsy workaround.

  There are other solutions on the market. For example, the Connex or Eden machines from Objet offer designers and engineers the opportunity to create realistic prototypes. The Connex can print as many as 11 different material properties in the same part at the same time. Additional technologies are also available from other 3D printer suppliers and additive-manufacturing vendors that can also add unique characteristics to a given prototype.

  Don’t get me wrong, a part produced with an SLA machine is very reliable and has served the prototyping world well for many years. However, it’s now time to reset our boundaries and embrace all of the other prototyping options on the market. Simply labeling every prototype part as an SLA part is underestimating the versatility and value of a good prototype produced with other processes and materials.

  Organizations should demand the optimal part to ensure they get the most realistic 3D rendering of their designs and have the opportunity to identify those critical design flaws early on. Ultimately these organizations will realize these benefits and bring better products to market faster.

  Additive manufacturing is a very effective tool that has given many organizations the competitive edge to meet their business goals and,  more importantly, satisfy their customers’ requirements. Prototyping with the right solution can help you achieve the high standards your company is striving for.

Bruce Bradshaw is the director of marketing at Objet Geometries. Send feedback about this commentary to [email protected].