Frequently Asked Questions

What can I expect from my prototype? Trends tips and pitfalls...

Choice is great but sometimes it slows us down.

Years ago, we turned to our local model maker for a protoype, then along came stereolithography and the start of rapid prototyping. Prototypes

Progressively, the additive world has made more and more of an impression, so today we deal with several processes and numerous materials.

At Plunkett Associates we are of the firm belief that speed does not have to equal additive, and as a consequence, still source model making and alot of CNC machining.

What is noticeable over the years is the increasing functionality we get (and expect) from prototypes and the blurring of the lines between prototypes and low volume production in both visual and performance aspects.


Primarily, prototypes are there to be tried and tested. Additionally, they may be required for marketing purposes where full aesthetics are paramount, or to sign off (or refine further) final product design. With so many low volume production options available, parts may also be used as a bridge to full scale production. Process choice will therefore depend hugely on the end goal.

(See article, “How can prototyping make my product a success?”)Testing prototypes


Test, test and test again. Make the most of this valuable opportunity…

Choose your material/process carefully.  Does this have to be as per production or would a different process or material give you what you need? This may depend on the end goal, time constraints and budget.

Don’t be afraid to fail. Use this opportunity to find any potential faults – that’s what this is all about.  There will inevitably be issues that weren’t anticipated but be flexible, think creatively and the design will progress.

Think laterally. It may be appropriate to focus on having more detailed physical prototypes of specific portions of your product.

Prototype partsBe patient. You may need to bounce back and forth between tweaking design plans and more prototypes if your product still has some issues.

Be brave! Don’t forget, prototyping is a means to an end, not the end. It’s easy to get caught up trying to build the perfect prototype. While you don’t want to rush the prototyping phase, you also don’t want to be stuck here for too long.

Think Speed. Be sensible about what you really need to achieve rather than what ‘might be nice’. For example, you don’t need to have custom injection molded parts made at this phase if machined and rapid prototyped parts will do the job just as well.

Be thorough, be prepared and be aware of all available options. For example, analysis software that can aid your design before needing to prototype, it may save time and money in the long run.High cosmetic prototypes

Pitfalls to watch out for

Media hype.  We are often led to believe anything is possible, especially when it comes to 3D printing! In reality, there are plenty of other processes that may be more suited to your requirements so always seek impartial, professional advice.

Expense.  Beware! Additive manufacturing may not always be the most cost effective option. The process and equipment can be very expensive, so be open to other more traditional technologies when considering the options.

Materials.  In some cases form and fit can be evaluated in any material. However, for testing function and manufacturability, actual material can be critical.

Confusion between prototype and finished product.  It is easy to start to believe that the prototype is actually the final system. However, expecting the prototype to accurately model the performance of the final product can be unrealistic.

Prototype for form and fitMisunderstanding of core objectives. Ensure the reasons for testing the prototype are clearly understood; otherwise it is easy to find tests are carried out somewhat blindly.

Excessive development of the prototype. This part of the process is supposed to be done quickly. It is easy to become stuck in irrelevant details, which can delay the final product being manufactured. Ultimately, we are all aware of how important prototyping is as a phase within product development. However, be mindful of the flexibility of options available now and seek advice you can trust.

Ultimately, we are all aware of how important prototyping is as a phase within product development. However, be mindful of the flexibility of options available now and seek advice you can trust.

We have been involved in prototyping for over 10 years and have access to all processes and materials, so for completely impartial advice, give us a call. We will look forward to talking to you.

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