Replace a broken part from a photo

A plastic clip snaps. A knob goes missing. A bracket cracks. The manufacturer no longer sells the part, or sells a whole assembly for the sake of one 5 cent piece. This playbook takes you from a photo to a printed replacement, and leaves you with a model you can improve.

You will need: the broken part (or the best remaining piece of it), a coin or ruler, calipers or a ruler for two or three key dimensions, and about 10 to 25 credits.

1. Take a photo the agent can measure

The agent measures from a photo by comparing the part against an object of known size in the same picture.

• Place a reference object next to the part, not on top of it: a coin, a credit card, or a ruler. Tell the agent which one it is.
• Shoot straight down. Hold the camera directly above, about 30 to 50 cm away. A tilted camera makes things look the wrong size.
• Lay the part flat on a plain, contrasting background in good, even light.
• Capture the important face. If the part has a main profile (like a clip's side view), shoot that. Take a second photo from another angle if the thickness matters.

2. Drop the image and describe the goal

Attach the photo to the prompt bar. Solid Vibes recognizes it as a photo of a part and shows its confidence. Then say what you want, including your reference and your key measurements:

This is a broken clip from my dishwasher basket. The coin next to it is a 2 euro coin (25.75 mm). Make a replacement. The slot in the rack is 4.2 mm wide, and the clip snaps in with a 1.5 mm hook. Make it a bit thicker than the original where it broke, and I will print it in PETG.

Use Smart mode for this one. Reading an image is the sort of request where extra reasoning pays off. A photo-to-model request costs 10 credits in Fast and 20 in Smart by default.

3. Review what the agent detected

Before it builds, the agent can show you a list of the values it read off the photo, each with a confidence, and flag anything ambiguous.

• Replace guesses with your caliper readings for critical dimensions.
• Answer any question it asks ("Is the hole through or blind?").
• Note anything the photo cannot show, like the thickness or hidden features.

These values become Parameters, tagged with an "image" source, so you can adjust them later.

4. Accept the first ghost

Look at the proposal from several sides. Check it against the real part. Hold the broken piece up to the screen if you like. When it looks right, Accept.

If it is close but off, use Tweak:

The hook is 1 mm too short and the base is 3 mm too narrow. Fix both, but keep the slot width at 4.2 mm.

5. Make it better than the original

Parts often break at the same weak spots. Ask for improvements:

Add a 2 mm fillet where the arm meets the base to reduce stress. Make sure the layers will run along the arm when printed. Recommend a print orientation.

A sharp inside corner is a stress concentrator, and a fillet there can improve strength substantially. Print orientation matters too, since layers are the weak direction. See Designing for 3D printing.

6. Check, test-print the critical bit, then print

Run the manufacturability check in Make for your printer and material. Then, before printing the whole part, print just the critical interface (the hook and slot) as a quick test, and check it against the real mating part. Adjust a fit_clearance parameter if needed. See Tolerances and fit.

Finally, export 3MF or STL and print.

Watch out

• A coin on top of the part, or at a different height, distorts the scale. Keep them on the same flat surface.
• Do not trust the photo for tolerances. Anything that has to fit snugly needs a caliper value.
• PLA is a poor choice for replacements that live somewhere warm or take repeated stress. PETG, ABS or ASA are better.
• If the original was a bought part with a standard size (a bearing, a screw), look it up in the library and use the real thing.

Credit estimate

Try it

Start from the Wall hook template, which makes a good stand-in for a broken hook or clip, and practice the improvement step:

Make this hook strong enough for a 3 kg coat. Add a fillet where the hook meets the wall plate, thicken the arm, and suggest a print orientation.