Things to consider when developing a product prototype

Things to Consider When Developing a New Product Prototype

October 27, 2026

Developing a new product prototype is an important stage between an initial concept and a finished product. A prototype gives designers and engineers an opportunity to see how an idea performs outside a drawing or digital model. It can reveal problems with dimensions, materials, usability, assembly, and manufacturing before significant resources are committed to full-scale production.

However, building a prototype is not simply about making a physical version of a design. The prototype needs to answer specific questions about the product and provide useful information for the next stage of development. According to the U.S. Small Business Administration’s guidance on product development and market research, understanding the intended market and customer requirements is an important part of developing a viable product.

From material selection to testing methods, several factors can influence whether a prototype provides meaningful results. Planning these factors early can reduce unnecessary iterations and make the transition to production more predictable.

Define What the Prototype Needs to Prove

Before creating a prototype, determine what you actually need to learn from it.

A prototype can be used to evaluate many different aspects of a product, including its physical dimensions, functionality, appearance, usability, or manufacturability. Trying to test everything with one prototype can make the development process unnecessarily complicated.

Establish specific objectives

Start by identifying the main questions the prototype should answer.

For example:

Does the product fit within the intended space?
Can users operate it comfortably?
Can the components withstand expected loads?
Do moving parts work correctly?
Can the parts be assembled efficiently?
Is the selected manufacturing method practical?

If the primary objective is functional testing, appearance may be less important in the first prototype. If the prototype is being prepared for user feedback or investor demonstrations, appearance may require greater attention.

For products requiring formed plastic components, working with experienced plastic thermoforming companies may also be considered when evaluating how a proposed design could translate into a production-oriented forming process.

Defining the purpose first prevents teams from spending time and money on prototype features that do not contribute to the current development stage.

Understand the Intended User

A technically successful prototype can still fail if it does not work well for the people who will use it.

Design assumptions should therefore be tested against real user requirements whenever possible.

Consider the user’s environment

Think about how, where, and how frequently the product will be used.

Important questions may include:

Will users operate it with one hand or both?
Does it need to work outdoors?
Will users wear gloves?
Does the product need to withstand repeated handling?
Are there accessibility requirements?
How much training will users need?

For example, a control panel may function correctly from an engineering perspective but still be difficult to operate if buttons are too small or poorly positioned.

Early prototypes can help identify these usability problems before they become expensive design changes.

Select Materials Based on the Application

Material selection can influence nearly every aspect of a prototype, from weight and durability to manufacturing cost and appearance.

A material that works well for visual mockups may not be suitable for functional testing.

Match material properties to the product

Consider the requirements of the final product rather than choosing a material simply because it is easy to obtain.

Depending on the application, you may need to evaluate:

Strength
Stiffness
Impact resistance
Temperature resistance
Chemical resistance
Weight
Flexibility
Surface finish
Dimensional stability

The National Institute of Standards and Technology’s materials research provides technical information and research related to material performance and manufacturing technologies.

Material selection should also account for the manufacturing process. A material that performs well in a prototype may require different tooling or processing conditions when production begins.

Choose the Right Prototyping Method

There is no single prototyping method that works for every product.

Depending on the design and development stage, teams may use 3D printing, CNC machining, thermoforming, injection molding, casting, or other processes.

Match the process to the objective

3D printing can be useful for quickly evaluating complex shapes and making design changes without producing expensive tooling. CNC machining can be appropriate when prototypes require specific engineering materials or tighter tolerances.

Thermoforming can be useful for creating plastic parts from heated sheets, particularly when the product requires relatively large, lightweight formed components.

For some projects, several methods may be used during development. A designer might 3D print an early concept to check dimensions, then create a more production-representative prototype using another process.

The best method is therefore the one that produces the information needed at the current stage.

Plan for Manufacturing From the Beginning

A prototype should not be developed completely separately from the eventual manufacturing process.

A design that works perfectly as a one-off prototype may be difficult or expensive to manufacture at scale.

Identify manufacturing constraints

Consider factors such as:

Available materials
Production volume
Tooling requirements
Part tolerances
Assembly methods
Cycle times
Waste
Finishing requirements

For example, a shape that is simple to produce with additive manufacturing may require significant changes for injection molding or thermoforming.

Considering these constraints early can reduce the risk of redesigning the product after testing has already been completed.

Pay Attention to Tolerances and Dimensions

Small dimensional differences can create major problems when several components need to work together.

A prototype should therefore include realistic tolerances when dimensional accuracy matters.

Avoid unnecessary precision

Not every dimension needs extremely tight tolerances. Excessive precision can increase manufacturing costs without improving the product’s actual performance.

Instead, identify which dimensions are functionally important.

For example, the diameter of a shaft that fits into a bearing may require much tighter control than the exterior dimensions of a protective housing.

This approach helps balance performance with manufacturability and cost.

Test the Prototype Under Realistic Conditions

A prototype that works on a workbench may behave differently under actual operating conditions.

Testing should replicate the environment the final product is expected to encounter as closely as practical.

Consider real-world stresses

Depending on the product, testing may include:

Repeated use
Impact
Vibration
Heat and cold
Moisture
Chemical exposure
Weight or pressure
UV exposure
Assembly and disassembly

Testing should also consider how the product may be misused. Users do not always interact with products exactly as designers expect.

The purpose is not necessarily to prove that the first prototype is perfect. It is to identify weaknesses that can inform the next design iteration.

Gather Feedback From More Than One Perspective

Engineers, designers, manufacturers, and end users may notice different problems.

A designer may focus on appearance and usability, while a manufacturing engineer may immediately identify an issue with tooling or assembly.

Build structured feedback into the process

Instead of asking whether people simply “like” the prototype, ask specific questions.

Useful feedback may include:

What was difficult to understand?
Which component was uncomfortable?
Where did assembly take too long?
Which feature was unnecessary?
What failed during testing?
What would make maintenance easier?

Documenting this feedback creates a clear record of what needs to change rather than relying on informal observations.

Consider Cost at Every Development Stage

Prototype costs can vary significantly depending on materials, quantities, tooling, labor, and manufacturing methods.

A low-cost prototype is not necessarily the most economical choice if it produces unreliable testing results.

Separate prototype cost from production cost

The most appropriate prototyping method may be more expensive than the eventual production method.

For example, a small batch of machined components may be suitable for functional testing even though the final product is expected to be manufactured through a high-volume forming or molding process.

Track prototype expenses, but focus on the value of the information gained from each iteration.

Plan Several Iterations

Product development rarely follows a straight line from concept to finished design.

The first prototype often reveals issues that were not visible during computer modeling or early design discussions.

Treat each prototype as a learning stage

A useful development cycle may look like this:

Define the problem.
Create the initial design.
Build a prototype.
Test it.
Record the results.
Identify necessary changes.
Build the next version.
Repeat until the design meets the required criteria.

The goal is not to eliminate every possible problem before making the first prototype. The goal is to discover important problems early, when they are easier and less expensive to address.

Conclusion

Developing a new product prototype requires more than turning a concept into a physical object. The prototype should provide useful evidence about whether the product can meet its functional, user, material, manufacturing, and cost requirements.

Defining the purpose of the prototype, selecting suitable materials and processes, considering manufacturing constraints, testing realistic conditions, and gathering structured feedback can make the development process much more effective.

Most importantly, prototyping should be treated as an iterative learning process. Each version should answer specific questions and provide information that improves the next version. This approach helps teams move from an initial concept toward a practical product with fewer unexpected problems during later development and production.

FAQs

What is the main purpose of a product prototype?

A product prototype is primarily used to test and evaluate a design before full-scale production. It can reveal problems with functionality, dimensions, materials, usability, assembly, and manufacturing. The information gained from testing helps designers make informed improvements before committing to larger production quantities.

Which prototyping method should a product developer choose?

The appropriate method depends on the product’s design, material requirements, testing goals, quantity, and development stage. 3D printing may work well for rapid design iterations, while machining, thermoforming, molding, or other processes may be more suitable when testing specific materials or production characteristics.

How many prototypes should be developed before production?

There is no fixed number because the complexity of the product and testing requirements vary. Simple products may need only a few iterations, while complex products can require many versions. The important consideration is whether testing has addressed the key functional, usability, durability, and manufacturing risks before production.

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