Mirror and invert: the two rules
A stamp prints its own mirror image, so the design must be mirrored before engraving. And because the laser removes material, everything that should not print has to be engraved away: the design is inverted, so the background is lasered and the letters stay raised. If one of the two is missing, the stamp prints backwards or prints the background.
- Mirror → the print reads correctly
- Invert → the background is removed
- Check both before the first test