Burr
A raised ridge or sliver of material left attached to an edge after cutting, drilling, milling or stamping.
What causes it
- Tool wear - burr size grows steadily as an edge dulls
- Feed and speed outside the window for the material
- Exit-side burring when a drill breaks through
- Stamping clearance drifting out of specification
Why human inspection misses it
Burrs are small, they sit on edges rather than faces, and they are often found by touch rather than by eye. On a line running thousands of parts an hour, nobody is running a gloved finger over every edge.
How it looks to a camera
Burrs break an edge that should be a clean line, so they are one of the more tractable classes optically - provided the resolution is fine enough that the burr spans several pixels.
Why it matters
Burrs cut hands, prevent parts from seating during assembly, break loose and contaminate assemblies, and interfere with coating adhesion. Because burr size tracks tool wear, a rising burr rate is also an early warning that an insert needs changing.
Adam detects burr along with five other defect classes. Upload a photograph of your part and see what it finds.