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Structural Prototyping And The Modern Design Process

Dec 15, 2020
5 min read

Prototyping tools and 3D printers are getting more affordable each year. Whether or not to invest in one is a complicated equation. Before you even get that far, it’s important to know what roles different prototyping options should play at each stage of the design process.

1. When do you need structural prototyping models?

Are you trying to get consumer feedback? Are you trying to ascertain technical viability? Or is it for internal use only? Are you looking for rapid prototypes to provide better internal communication and consensus? Or are you trying to test a new packaging shape on production, labeling, or filling lines?

2. Where are you in the design process?

Early in design exploration, you probably don’t need prototypes. Sketches and rough mockups actually have advantages over prototypes in that they can filter through more ideas in shorter time—and separate the wheat from the chaff. What you can learn, and what is the most efficient way to learn it, is different at each stage of the design process. Having the appropriate tactile stimuli for testing each use context is a learned art.

3. How can you make the process efficient?

Ask a lot of questions up front. Determine the objective of the particular prototype that you, the product team or a client is requesting. Always start with solid shapes because they are less expensive and will allow you to explore the basic feel of products and packages. Hold off on high-end functionality until you narrow down the options to a few strong possibilities in your front end design and development phase.

4. 3D Models help refine your design feasibility.  

At some point along the design and development process, you will need to turn your sketches into 3D models. These 3D models will help you refine your structural and creative design and will help you to build in critical attributes like: capacity requirements, finish requirements, wall thickness estimates, structural L-W-D foot print, and brand embossing.

5. Is it a visual or a functional prototype?

There’s a clear line to line to draw between the evaluation and use of a “visual” prototype and a “functional” prototype. Visual “shelf ready appearance model” prototypes can be used for sales presentations or photography, but “early-read” functional attributes should be evaluated with unpainted durable prototypes manufactured from materials such as SLA, SLS, Object, or Starch models. In some cases, prototypes can be manufactured with the same material planned for production. Evaluating your 3D prototype model’s performance or manufacturability, could also be evaluated with virtual simulation or modeling at this point.

6. What design elements can you get the best feedback on?

One of the best prototyping contexts is using hollow “shelf ready appearance model” shapes to explore the basic hand-feel and balance of the package. Will it pour with a good, ergonomic balance for the consumer? How will the balance change as the contents of the package become less? As the design is refined, you will want to test how efficiently it runs on filling or labeling lines.

7. Be aware of time-consuming pitfalls.

The most common pitfalls are too little, too late, and too much, too soon. Too little, too late means you could have worked out some design issues earlier in the process with prototypes that elicited better feedback. Too much, too soon means you wasted time and money on design prototypes that weren’t viable, and you could have learned the same lessons another way.

8. Explore customization and management SKU platform.

Prototyping for brands with many SKUs or extension lines can help explore customization options that remain under a single brand or product umbrella. You can maximize the versatility of the flagship product by creating a platform that’s easily extendable—before production begins.

9. Prototype simulation and modeling.  

Ahead of going down the path of cutting metal to create manufactured product prototypes from single cavity or lead mold tools- evaluate the option of taking your 3D prototype model through a virtual simulation and modeling exercise to help evaluate the performance of the structure.  As an example, the squeezability or top load yield force of a filled (or unfilled) structure can be computer simulated with decent accuracy.  Your chosen structure manufacture or a third party testing company like Plastic Technologies Incorporated can perform these virtual simulations.

10. Tighten up the specs.

Confirm the critical performance and design attributes with actual manufactured product prototypes utilizing the same material choice and production technique planned for production. Manufacturing production prototype samples with a single cavity or lead tool prototype is a recommended cost-effective method to evaluate the feasibility of manufacturing the structure and to validate the structure’s performance on your filling and labeling lines. Understand the limits of your unit cavity prototype to hit the required specifications and plan for variances with design mitigation planning.

11. Outline a timeline of development.

Sometimes speed to market wins, and companies will go with the first design that works. Those instances are the exceptions to the rule. More often, numerous prototype iterations are required to satisfy all the design attributes and performance requirements a package must meet along the commercialization path and include delivery of brand intent through total package system delivery in the supply chain.

12. Know the limitations.

Realize that a prototype won’t let you completely understand the package in every detail. Only actual production samples are production level. The squeezability of a plastic container is still very difficult to replicate physically with a prototype. Virtual simulation and modeling using computer software can often help in such cases, as well as designing for top-load strength.

13. Manage expectations.

Any prototype sample in circulation should be production-capable, so always ask. It’s not worth the headache and frustration to entertain a design that can’t be manufactured. It’s critical to still build in the appropriate lead time in actual pre-production, which doesn’t necessarily change once you have a prototype in hand.