The request sounds simple: make a prototype of this product. But that can mean a shape to hold, parts to assemble, a mechanism to test or an object to photograph. These tasks may need different models. Asking one build to do them all can spend the budget before the most important question has an answer.
Start with one sentence: after this test, we need to decide whether to continue, change or stop a specific part of the design. That sentence is more useful to a prototype brief than a request for something that looks finished.
Separate appearance, fit and function
An appearance model helps people judge form, colour, finish or presentation. A fit model checks relationships between parts. A functional prototype tests a defined behaviour under stated conditions. These purposes can overlap, but the overlap must be planned.
Consider a hypothetical handheld device. A simple size model can show whether it fits a pocket or whether a button is easy to reach. It cannot establish battery life. A separate latch test may need representative materials and a repeatable opening cycle, while a painted photo model may need neither.
Write a pass condition before ordering
Replace “test the handle” with a task someone can observe. Who will hold it? What will they do? Which dimensions are being compared? What result would make the team change the design?
Record the conditions as well as the result. If the model is lighter than the intended product, a positive handling response has that limit. If parts were adjusted by hand to assemble, record the adjustment. Otherwise the next person may mistake a successful demonstration for proof that the original geometry fits.
Spend detail where it changes the answer
A rough surface can be acceptable for a size check and unacceptable for a finish review. A simplified internal structure may be fine for photography but misleading for a stiffness test. Choose the build method and material after defining the purpose, not because a particular machine is available.
State which parts must be representative and which may be simplified. A prototype made with a different process or material does not automatically predict the final product's performance. Neither does a working sample establish certification or manufacturing readiness.
Make revisions part of the scope
Ask what happens after the first review. Does the quote include a design change, another model, or only delivery of the initial build? Keep the reviewed file version with the notes. If the next model changes material and geometry at once, it may be harder to tell which change caused the result.
There is no useful universal price for “a prototype” without this scope. Quantity, geometry, material, finish and the work needed to prepare the design all matter. A clear brief lets suppliers quote the same job.
Copy this briefing prompt
We are developing: [product and intended user].
The next decision is: [one question].
We already have: [sketches, dimensions, CAD or an existing product].
The test will be: [task, conditions and pass criterion].
These features must be representative: [list].
These features may be simplified: [list].
We need: [quantity], by [date], within [budget range].
Files and current revision: [link].
We also need photography or launch content: [yes, no or undecided].
Bring the question, even if the design is early
You do not need a complete technical specification to start. Mark what is unknown. BDWY can help define a prototype scope around the decision, then discuss whether digital work, a physical model or both are appropriate.
BDWY Studios
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