Scratch
A linear mark where material has been abraded away, usually by contact with something harder than the part.
What causes it
- Swarf or chips trapped between the part and a fixture
- Contact with conveyors, chutes or other parts in transit
- Abrasive contamination in a wash or deburr stage
- Handling without gloves or protective packaging
Why human inspection misses it
Fine scratches are strongly direction-dependent: the same scratch can be obvious from one angle and invisible from another. Inspectors tilt a part to find them, which does not scale.
How it looks to a camera
Scratches are high-contrast linear features and read well once lighting is controlled. The difficulty is distinguishing a genuine scratch from the directional grain of a machined or brushed finish.
Why it matters
On a sealing or sliding surface a scratch becomes a leak path or a wear initiation site. On a finished surface it is a reject.
Adam detects scratch along with five other defect classes. Upload a photograph of your part and see what it finds.