How to give useful feedback on a 3D model

Your designer has sent you a 3D model and asked for feedback. If you've never reviewed one before, it's easy to freeze, or to write "looks great, maybe a bit more modern?" and hope for the best. This guide shows how to give feedback on a 3D model that your designer can act on straight away, so you get what you want in fewer rounds.

You don't need any 3D experience. You need to know what you want, and a few habits that make it easy to explain.

#What makes 3D feedback useful?

Useful feedback answers three questions for the designer:

• Where? Which part, which side, which edge.
• What? What should change, and roughly by how much.
• Why? What you're trying to achieve. The reason often lets the designer suggest a better fix than the one you asked for.

Vague feedback misses at least one of these. The designer then has to guess, and a guess costs you a round.

#Good and vague notes: examples

You don't need exact numbers. "About a finger's width" or "roughly half as thick" is enough for a designer to work with. If you do know a dimension, give it.

#How should I write my notes?

1. 1

   One note per issue

   Put each change in its own note, pinned to the spot it's about. "Lid edge too sharp" and "logo too small" are two notes, even if they're close together. Separate notes can be answered, fixed and ticked off one by one, and nothing gets lost in a long paragraph.

2. 2

   Point, don't describe

   "The second screw from the left on the back panel" is hard to find. Clicking the screw is not. If your review tool lets you pin notes on the model, use that rather than a separate email.

3. 3

   Say what and why

   "Make the base wider so it doesn't tip over" gives the designer the goal as well as the request.

4. 4

   Mark your priorities

   Start a note with Must, Should or Nice to have. If the budget or the deadline gets tight, the designer knows what to protect.

5. 5

   Separate taste from requirements

   "I'd prefer it rounder" and "it must fit a 60 mm opening" are different kinds of feedback. Saying which is which avoids arguments later.

6. 6

   Collect the team's views first

   If three people at your end have opinions, agree before you send. Conflicting notes from different people in the same round are the most common cause of extra rounds.

#What should I look at in a 3D model?

A quick routine for each round:

• Turn it all the way round. Check the back and the underside, not just the front view it opened on.
• Zoom in on the details. Logos, text, seams, buttons and edges.
• Check sizes you care about. If your viewer has a measure tool, measure the dimensions that matter to you.
• Compare with the brief. Have the points you raised last round been dealt with?
• Remember what it isn't. An early model may have placeholder colours or rough materials. If you're unsure whether something is final, ask in a note rather than marking it as a problem.

#How do I approve a 3D model?

Approval tells the designer the version is finished. It usually ends the included revisions, so it's worth being sure:

• Check that every change you asked for has been made or answered.
• Make sure the person who has the final say has seen it.
• Approve the exact version you've reviewed, such as "v3", not "the latest one".
• If you still have small comments, send them first. "Approved apart from the logo colour" isn't an approval, and treating it as one causes confusion later.

If you're not ready to approve but have no changes, say that too: "No changes from me, waiting on our sales team" saves the designer chasing you.

#Leaving notes on a MeshMarkup review link

If your designer sent you a MeshMarkup link, it opens in your browser with no account and nothing to install. The panel beside the model says who sent it and, if they set one, the date they'd like feedback by.

1. 1

   Turn the model

   Drag to turn and scroll to zoom (on a phone, pinch). To check a distance, click More tools on the left, then Measure, then two points.

2. 2

   Pick the spot

   Click the spot you mean, or click Add a note at the bottom of the model and then the spot. Dragging only turns the model, so you won't add a note by accident.

3. 3

   Choose the spot or the whole part

   If the spot is on a named part, choose This spot or All of that part.

4. 4

   Write the note

   Type your name the first time, then what you'd like changed. Tick Email me when your designer replies if you'd like an email back.

5. 5

   Add it

   Click Add note. It's saved straight away with the view you had, and the designer can see it.

If your designer pinned questions for you, answer each with Looks good or Needs a change. If you're happy with everything, No changes, looks good at the foot of the panel tells them so; you can still add notes afterwards. When they send a sign-off link, you'll see a button such as Approve v3, which works once all notes are closed. See what your client sees.

#Questions

#Do I need 3D software to review a model?

Usually not. Most designers send a link that opens in a browser, or images and a video. Ask your designer what suits you.

#Is it all right to say I don't like something without knowing why?

Yes. Say so, and say what you'd like it to feel like instead, perhaps with a reference photo. "Too clinical, more like a kitchen appliance than a lab tool" gives the designer a direction.

#How long should I take to review?

Ask your designer when they need it, and block time to look properly. Feedback in one batch is faster for everyone than notes arriving over a week.

#What if I change my mind after approving?

Tell your designer as soon as you can. Changes after approval are usually new work with their own price and timeline, so check your agreement first.