A practical brief template for manufacturers: inputs, outputs, revision control and what to agree before CAD work begins.
Why a clear CAD brief matters
A good engineering brief is less about writing a long document and more about removing the assumptions that slow down a design team. Two people can interpret “make it manufacturable” differently: one may think of geometry, while another needs supplier parts, assembly access, inspection dimensions and a purchase-ready BOM.
Before any modelling begins, agree what the CAD work must enable: a supplier quotation, a fit check, a prototype, a laser-cutting job or a complete production release. The deliverables will differ for each.
1. Explain the product and intended manufacturing route
Describe the assembly’s purpose, the environment in which it operates, expected loading or handling conditions, and how the part will be made. Identify whether the design involves machining, fabrication, sheet metal, welding, additive manufacturing or purchased components.
- State the main functional requirements and envelope or packaging dimensions.
- Share photos, reference products, hand sketches and any existing CAD.
- List fixed interfaces, installation clearances and service access.
- Identify known materials, suppliers and in-house manufacturing constraints.
2. Separate known dimensions from assumptions
A sketch with a few dimensions can be enough to begin a concept, but it is not always enough to release a manufacturing drawing. Mark measurements as confirmed, approximate or to be determined. Call out the features that control fit, movement or safety.
For reverse-engineered parts, identify whether the digital model is intended to reproduce existing geometry or improve it. A scan does not automatically establish the correct nominal dimensions or tolerances.
3. Define deliverables before discussing price
A “3D model” can mean a visual envelope or a fully editable parametric design with an assembly structure. Similarly, a drawing can be a reference sheet or an inspection-ready manufacturing document.
- Native editable CAD or neutral STEP export.
- Assembly model, exploded view and parts list if needed.
- Dimensioned PDFs, DXF files, cut lists or shop drawings where applicable.
- BOM detail, revision table, part naming and folder structure.
- Number of review cycles and the final handover format.
4. Set review and ownership rules
Define who approves dimensions, tooling choices, code requirements and final production use. Agree how comments will be shared, which files are considered released and how changes will be tracked. A brief review of critical interfaces early in the project is usually more useful than discovering a fit problem after every drawing is completed.
A brief you can send today
A practical first enquiry can contain just six items: what the product does; reference files; required geometry or interfaces; preferred manufacturing process; outputs needed; and an expected schedule. If a requirement is unknown, mark it as open rather than guessing.
For related examples, explore our engineering portfolio, including caravan and fabrication projects, or visit mechanical CAD services to discuss a scope.