Document Coordinate Origins Across a PCB Release Package

Two manufacturing files can describe the same board shape yet disagree about where that board sits in the coordinate system. This becomes especially confusing when board-level assembly data is combined with panel-level fabrication data. Document the coordinate frame used by each deliverable.

Altium’s PCB setup tutorial distinguishes the editor’s absolute origin from a user-defined relative origin. Export and downstream setup choices must be reviewed with that distinction in mind.

Create a coordinate-frame map

For each output, identify units, origin location, axis directions, board side convention, and whether the data represents one board or the panel. Note any intentional translation, rotation, or mirroring performed downstream. A coordinate list without this context is incomplete. Include the convention used for bottom-side assembly positions, because a supplier may transform that view differently from the fabrication layer display. Verify the convention with sample coordinates.

Use recognizable physical features to connect the frames. Select multiple non-collinear points, such as tooling holes or well-defined board features, so a mirror or rotation cannot be mistaken for a simple translation.

Verify relationships rather than one point

Import the actual exported files into the receiving workflow or an appropriate independent viewer. Check the selected reference points and overall orientation. One coincident origin can hide a mirrored file, while one coincident hole can hide a rotation about that hole.

Do not repair an unexplained mismatch by dragging layers until they look aligned. Determine which file used a different frame and correct the export or document the approved transformation. Manual alignment without recorded parameters is difficult to reproduce.

Control changes to the datum

When the board origin moves, review every output affected by coordinate values even if physical geometry is unchanged. Regenerate the complete related set and check that older coordinate files are not retained beside newer layers.

For panels containing repeated boards, distinguish the board-local frame from each instance’s placement in the panel. The transformation should be explicit enough for assembly, test-fixture design, and inspection teams to use consistently.

Preserve the frame map with the release package and include a small annotated view showing the origin and axes. That reference removes ambiguity without requiring downstream users to infer coordinate conventions from file extensions or from whichever preview opens first.