Reverse Engineering a Broken Part
How to measure, photograph and describe a broken part so an Australian maker can reverse-engineer and 3D print a replacement.
Reverse engineering is the process of turning a real-world object into a 3D model so it can be re-printed. The more useful information you give your maker upfront, the cheaper and faster the job — and the better the first-print fit. Here's exactly what they want.
What to send (in order of usefulness)
1. The actual broken part. Even in pieces. The maker can measure it, scan it or test-fit prints against it. This is by far the best starting point.
2. The mating part. If the broken piece clips into something, send a photo of that something — the geometry the new part has to fit into matters more than the broken part itself.
3. Calliper measurements. Critical dimensions: overall length/width/height, hole diameters and centre-to-centre spacing, snap-fit gap widths, thread sizes.
4. Photos from multiple angles. Top, bottom, both sides, both ends, plus a close-up of any feature that matters. Always include something for scale — a ruler, calliper, coin or stamp.
5. Original part number and a manufacturer parts diagram if you can find one online (try the brand's service manuals, eBay listings, owner forums).
How to photograph a part
Use natural daylight, not flash. Lay the part on a plain background — a sheet of white A4 paper is perfect. Take one photo from each of the six faces (top, bottom, front, back, left, right) with the part squared to the camera and a ruler in the frame.
Add detail shots of anything fiddly: snap features, threaded holes, complex curves. Mark anything broken with masking tape and write 'broken' on the tape.
How to measure
Digital callipers are ideal — cheap ones from Bunnings or Jaycar are accurate enough. Measure to 0.1 mm. For each dimension that matters, write the value directly onto your photo (or send a sketch).
If you don't have callipers, a ruler and a clear photo will get you close enough for many parts — your maker can refine the fit on a test print.
What it will cost
Reverse engineering adds a one-off design fee on top of the print cost. For a simple bracket or clip, expect $30–$80. For a more complex part with curved surfaces or threads, $80–$250. Once the part is modelled, future prints of the same part are just the print cost.
Some makers will reduce or waive the design fee if you're ordering 10+ units of the same part.
Iterating to a good fit
Always order one print first. Trial fit it, mark anything that needs to change with a marker, and send the maker a photo showing the issue. A 0.2 mm shift or a slightly wider snap is usually a 10-minute change and a quick re-print.
FAQ
Do I need to send the broken part by post?
Usually not for the quote — good photos and measurements are enough. Some makers will ask to receive the part for complex geometry; it's worth the postage.
Can you scan a part?
Yes — some Australian makers offer 3D scanning for complex organic shapes. It's overkill for most clips and brackets but invaluable for car body parts and handles.
Can you make it better than the original?
Often, yes. If the original failed in a known way, your maker can thicken a wall, add a fillet or change the material to make the replacement more durable than the part it replaces.
Ready to get something printed?
Post a job and Australian makers will quote you within hours.