How to Number Mosaic Pieces for Laser Cutting and Backside Engraving
Number the pieces before cutting so dozens of similar tiles can be engraved, sorted, finished and returned to the correct position during assembly.
Numbering is one of the simplest ways to turn a complicated mosaic from a puzzle into a repeatable shop process. Once the pattern reaches a few dozen pieces, many tiles begin to look similar after they are removed from the sheet. If those pieces are also stained in different colors, keeping track of their position becomes even harder.
The most reliable approach is to assign each tile a number before export and engrave that number on the back of the physical piece.
Why backside numbering matters
A number on the front face would interfere with the finished artwork, so the identification mark belongs on the back. Backside engraving lets the visible face remain clean while giving every tile a permanent reference during staining and assembly.
The numbering map also becomes useful outside the laser. A stain planner can group tile numbers by finish, and the final numbered preview can be kept next to the workbench while the mosaic is glued together.
1. Number the pieces while the geometry is still known
Do not wait until after the SVG has been heavily edited. The generator already knows the closed pieces and their positions, so it can place a readable number inside each tile. MosaicGenny's numbering tools use the detected piece geometry to place labels away from the cut edges whenever the tile is large enough.
If a tile is extremely small, there may not be enough safe space for a useful number. That is another reason to avoid unnecessarily tiny fragments in a production mosaic.
2. Decide which way the backside layout must mirror
Turning a physical board or set of tiles over changes the relationship between the front layout and the back. If you want the engraved numbers to match the correct pieces when viewed from the back, the tile positions need to be mirrored.
MosaicGenny supports left-to-right and top-to-bottom backside mirroring. The geometry moves to the mirrored position while the digits themselves remain readable. Choose the mirror direction that matches how you will physically flip or handle the workpiece.
3. Keep cut lines and numbers on separate operations
In LightBurn, the mosaic boundaries should use the settings required to cut the material. The numbers should use a much lighter engraving operation. Treating both as the same laser operation can waste time and may cut unwanted shapes into the back of the pieces.
MosaicGenny exports the number geometry separately from the cut geometry so it is easier to move those elements onto different LightBurn layers.
4. Use a numbering direction that is easy to reference
A consistent numbering order makes the assembly map easier to scan. MosaicGenny's production tools use a predictable tile order so the same numbers can carry through into color and stain sorting guides. The exact numeric order matters less than keeping it stable from SVG generation through finishing.
5. Preserve the number through the finishing workflow
Once the pieces are cut, keep the engraved side visible while sorting. If you are staining several colors, make separate trays or stacks for each finish. A CSV sorting guide can tell you which numbers belong in each group.
After the finish dries, the permanent engraving still identifies every tile. That is much more dependable than removable tape labels, which can fall off or become unreadable during sanding and staining.
6. Assemble from the same reference used during design
Keep a numbered preview on a nearby screen or print a reference copy. Begin with distinctive perimeter or center pieces, then work through the surrounding numbers. For a large design, assemble one region at a time rather than dumping every tile onto the bench at once.
Recommended numbering workflow
- Finalize the mosaic geometry.
- Enable piece numbering.
- Select the backside mirror direction that matches your physical workflow.
- Export the SVG.
- In LightBurn, separate numbers from cut lines.
- Engrave the numbers on the back and cut the pieces.
- Sort numbered tiles by stain or paint color.
- Finish the pieces in batches.
- Reassemble using the numbered reference map.
Generators with numbering support
The Traditional, Curved, Shattered and Symmetric MosaicGenny workflows are designed around numbered production pieces and backside-layout options.