3D modelling brief: how to write one that gets the model right first time

A good 3D modelling brief answers, before you start, the questions you'd otherwise discover in round three: what the model is for, how big it is, what it's made of, how much detail it needs and what file the client expects at the end. Most "the model is wrong" moments aren't modelling mistakes. They're a missing line in the brief.

This guide is for 3D artists, product visualisers and engineers who take briefs from clients, and for clients who want to write one. There's a template at the bottom you can copy into an email or a document.

#Why do 3D projects go wrong at the brief?

Because a client usually describes what the thing looks like, and a 3D model also needs to know what it's for. "A model of our new kettle" could mean a hero render for a billboard, a light model for a web configurator, a 3D print for a trade show or a STEP file for the toolmaker. Those are four different jobs with different polygon budgets, detail levels, deadlines and prices.

The other common gaps are scale (nobody gave a dimension, so the model is "about right"), materials (the client imagined brushed steel, you modelled polished chrome) and approval (the person who briefed you isn't the person who signs it off).

#How to write the brief, step by step

1. 1

   Start with the use, not the object

   Write one sentence on where the model ends up: "Product renders for the Amazon listing and the box", or "A GLB for the website's 3D viewer". Everything else follows from this: the detail level, the file format, whether the back needs modelling at all.

2. 2

   Collect the references in one place

   Ask for drawings, photos, CAD files, competitor images and anything the client likes or dislikes. Number them, so feedback can say "like ref 4, not ref 2". If there's a physical sample, ask for photos from the front, back, sides, top and underneath, with a ruler in shot.

3. 3

   Pin down the dimensions

   At least the overall width, height and depth, with units. For anything that has to fit something else, get the critical dimensions too, and agree which source wins if a drawing and a photo disagree.

4. 4

   List materials and finishes per part

   Not "plastic, black" but "body: matte black ABS, light texture; button: gloss red; logo: pad-printed white". Ask for colour references (a Pantone or RAL number, or a physical swatch photographed in daylight) if colour matters.

5. 5

   Agree the level of detail

   Say what can be simplified. Screw threads, internal parts, cable ends and text on labels are common candidates. A hero close-up needs them; a web model usually doesn't.

6. 6

   Name the deliverables

   File formats, polygon or file size limits, texture resolution, whether you hand over the source file, and how many renders at what size.

7. 7

   Write down who approves and by when

   One named person who gives the final yes, the date for first feedback, and how many revision rounds are included.

8. 8

   Send it back as a summary and get a yes

   Even if the client wrote the brief, send your version back: "Here's what I understood. Anything wrong?" A reply saying "yes, that's right" is the most useful line in the whole project.

#What questions should I ask the client?

If the client sends a one-line request, these questions fill most gaps in one email:

• What will the model or renders be used for, and where will people see them?
• Do you have CAD, drawings or a physical sample? Can you send photos with a ruler in shot?
• What are the overall dimensions, and which ones have to be exact?
• Which parts are which material and colour? Do you have colour codes?
• Does the inside, the back or the underside need to be modelled?
• Is there a logo or text on it? Can you send it as a vector file?
• What files do you need at the end, and is there a size limit?
• Who signs it off, and when do you need the first look?

Ask them all at once. Five separate emails over a week are how a two-day job becomes a three-week one.

#What does a good 3D brief look like?

Copy this, delete what doesn't apply and fill in the rest. The example lines are there to show the level of detail that helps; swap in your own.

3D MODELLING BRIEF

Project:           [Name]
Client contact:    [Name, email]
Approves the work: [Name, if different]

1. PURPOSE
What it's for:     e.g. Product renders for web shop and packaging
Where it's seen:   e.g. Website at full screen, printed box at 15 cm wide
Closest view:      e.g. Close-up of the dial, filling the frame

2. REFERENCES
Files attached:    e.g. ref-01 drawing.pdf, ref-02 to ref-06 photos
Source of truth:   e.g. The drawing wins over the photos
Likes / dislikes:  e.g. Like the lighting in ref-05, not the background

3. SIZE
Overall (W x H x D): e.g. 180 x 240 x 160 mm
Must be exact:     e.g. Lid diameter 96 mm, handle gap 30 mm

4. MATERIALS AND FINISHES (per part)
Part:              Material / finish / colour code
e.g. Body:         Brushed stainless steel
e.g. Handle:       Matte black plastic, RAL 9005
e.g. Logo:         Laser-etched, from logo.svg

5. DETAIL LEVEL
Model fully:       e.g. Everything visible from outside
Can simplify:      e.g. Internals, screw threads, cable
Leave out:         e.g. Underside (never shown)

6. DELIVERABLES
Files:             e.g. GLB under 15 MB, plus the source file
Renders:           e.g. 6 angles, 3000 x 3000 px, white background
Textures:          e.g. 2K maximum

7. SCHEDULE AND ROUNDS
First look by:     [Date]
Final files by:    [Date]
Revision rounds:   e.g. 2 included (see quote)
Feedback within:   e.g. 3 working days of each round

8. NOT INCLUDED
e.g. Animation, packaging design, extra colourways

The "Not included" section does as much work as the rest. It's much easier to agree it now than to argue about it at round three.

#How much detail is too much?

A brief should take the client 20 to 40 minutes to fill in, as a rough guide, not a day. If it's turning into a specification document, the project probably needs a paid discovery stage first, or a quick blockout (a rough, untextured model of the main shapes) that the client approves before you spend time on detail.

A blockout is the best brief check there is. It costs a few hours and shows straight away whether you and the client imagined the same proportions.

#Where MeshMarkup helps

Once the brief is agreed, the next risk is the first review turning into an email thread about "the bit on the left". In MeshMarkup you can put the brief's reference images or the brief itself as a PDF next to the model with Add images, so the client sees the model and the references in one link. Send the blockout with Share for review and a Leave feedback link, and the client clicks the spot they mean to leave a numbered note, with no account. If size matters, Measure lets you both check a dimension against the brief.

See send a 3D model to a client for feedback and renders, snapshots, images and PDFs.

#Questions

#Should the client or the 3D artist write the brief?

Either, but the artist should always send back a written summary. The client knows the product; you know what a 3D model needs. The brief is finished when you both agree on the same page.

#What if the client has no drawings or dimensions?

Ask for photos with a ruler or a known object in shot, and one or two measured dimensions you can scale from. Write in the brief that sizes are estimated from photos, so nobody is surprised later.

#Is a blockout worth charging for?

Usually it's part of the first round rather than a separate fee. It saves you rebuilding a detailed model because the proportions were off.

#How do I handle a brief that changes halfway?

Update the brief, date it, and send it back for a yes. Then check it against your quote: a new use or a new part is often a change in scope, not a revision. See how many revision rounds to include in a 3D design quote.