My laser cuts twice over the same line

When two cut shapes share an edge, the laser follows both outlines and cuts the shared edge twice. That chars wood, melts acrylic edges and wastes time.

In DIYCutLab

The check reports duplicated cut lines with the parts involved. Fix them before export:

1. Select the shapes that touch.
2. Combine shapes → Union to merge them into one outline, so the shared edge disappears.
3. Or move them apart: leave at least 1 mm between parts.
4. Delete accidental copies — duplicates exactly on top of each other look like one shape. Open Objects to see them in the list.

In files from elsewhere

If you open a file in your laser software and see lines cut twice, look for a "remove overlapping lines" or "delete duplicates" function, or edit the file in DIYCutLab: import it, union touching shapes, and export again.

What counts as duplicated

Two cut segments are duplicates when they run in the same or opposite direction along the same line within a small tolerance and overlap by more than a few tenths of a millimetre. Touching at a single point is not a duplicate.