SCALE P60 CALIBRATION MARKER
All dimensions are millimetres. Tile 60 x 60 mm; QR symbol 45 x 45 mm.
Total height 0.8 mm: white base 0.6 mm, black symbol 0.2 mm.

Import both STLs together as parts of one object, preserving their coordinates.
Assign matte white to the base and matte black to the symbol. Do not auto-arrange
or drop the symbol to the build plate separately. Print at 100% scale.
For a single extruder, use the OpenSCAD all-parts model and change from white to
black at Z=0.6 mm. Use 0.2 mm layers and a fine enough nozzle for the modules.
Check the final QR symbol width with calipers; enter the measured width in the app.
Confirm your phone reads the finished marker before relying on it.

For accurate capture, the TOP of the QR symbol must be coplanar with the drawing.
Recess the marker or raise the drawing by its 0.8 mm total height.
A paper marker is preferable if you cannot align these planes.
Do not cover any of the white quiet zone. No glossy finish.

This is a practical calibration reference, not a certified measuring instrument.
The SVG and PDF offer a thin paper alternative. Print the PDF at Actual size.
