If the printhead hits the wall despite the distance control being activated, this can have two different causes.
1. A sudden unevenness in the wall.
The distance control cannot compensate for sudden strong unevenness. Please check the wall for such unevenness before printing and compensate for it during printing by increasing the distance at these points via the software.
2. The wallPen is not parallel to the wall.
If the wallPen is not parallel to the wall, the right side of the print head with the laser may be further away from the wall than the left side. As a result, the distance is displayed correctly in the software and is also correct on the right side, but the left side is much too close to the wall and touches it accordingly.