Reverse engineering
When you have the part but not the drawing.
A bracket has broken, the spare part is no longer made, and a CAD file never existed. Then the part itself is the source: I scan it and derive a model from it that can be manufactured.
Where it pays off
These are the three cases where a scan makes the difference.
Spare part with no source
The machine runs, a plastic part has broken, and the manufacturer no longer supplies it. The broken piece is enough as a source, as long as the shape is still readable.
Fitting to something existing
A new part has to match an existing contour, say a bracket to a housing or a seat to a shaft. The scan gives you the counter-form instead of measuring and guessing it.
Small run from a pattern
Twenty are needed where one exists, all alike. The scan becomes a model, and from then on every part is like the next.
What I measure with
Three devices, because they cover different sizes and ways of working. The figures are the manufacturers’ own.
3DMakerPro
Toucan
My device for out and about. It works without a computer attached, and the size range runs from a small part to a piece of furniture. It is the only one that also captures surface colour.
- Accuracy
- 0.03 mm (near)
- Resolution
- 0.05 mm (near)
- Object size
- 10 – 4,000 mm
- Working distance
- 200 – 1,000 mm
- Frame rate
- 15 fps
- Light source
- blue structured light
- Colour texture
- yes
3DMakerPro
Moose Lite
For smaller parts at the workbench. It runs off the computer and is quickly set up there, when a part is with me anyway.
- Accuracy
- 0.05 mm
- Resolution
- 0.10 mm
- Object size
- 15 – 1,500 mm
- Working distance
- 150 – 400 mm
- Frame rate
- 10 fps
- Light source
- near infrared
- Colour texture
- no
Creality
CR-Scan Lizard
Scanning here started with this one. It still does what it always did; for new jobs I now reach for the other two.
- Accuracy
- 0.05 mm
- Resolution
- 0.10 mm (up to 0.2)
- Object size
- 15 – 2,000 mm
- Working distance
- 150 – 400 mm
- Frame rate
- 10 fps
- Light source
- near infrared
- Colour texture
- no
The best scanning accuracy is 0.03 mm and therefore below the production tolerance of 0.2 mm over 100 mm edge length. As a rule the source is not the limiting factor, the print is.
What can be scanned, and what cannot
A scanner works with light, and some surfaces give it little back. So that you know beforehand rather than with the invoice, both are listed side by side.
Well suited
- Matte, light surfaces in plastic, wood or painted metal
- Parts from a few centimetres up to about shoebox size
- Shapes with readable geometry, even where they are damaged
Difficult to impossible
- Shiny and bare surfaces. They can be matted down, but that is an extra step
- Transparent material such as glass or clear plastic
- Deep, narrow undercuts that no light reaches
- Fine threads and fits. A caliper is usually the more precise choice here
How it runs
- 1
You send me a photo
Before anything costs money, I look at whether the part can sensibly be scanned at all. Sometimes the answer is no, and then I say so.
- 2
The original comes to me
By post or dropped off. Scanning does nothing to the part; it goes back as it came.
- 3
Scan and rework
The point cloud becomes a clean surface. A broken edge is filled in along the way. That is handwork, and it is the actual task.
- 4
Model and production
You get the part printed, and the file with it if you want. Then you can simply reorder next time.
A photo is enough to start.
Send me a picture of the part and what it belongs to. I will tell you whether a scan is the right way, and if not, which way would be.