A global solder-mask or paste setting may appear to have no effect on a few pads. The reason can be a local override inherited from a footprint or applied to an individual pad. Investigate that hierarchy before making a larger global change that alters every other component.
The KiCad 10 PCB Editor manual describes board defaults and footprint- or pad-level overrides for mask and paste. The resolved opening is what fabrication receives. A screenshot of the board-level setting alone does not establish the actual output geometry.
Start with one unexpected aperture
Identify the exact reference designator, pad, layer, and measured opening. Compare it with a similar pad that behaves as expected. Record the copper size separately from the mask or paste aperture so the investigation does not confuse a pad change with an opening change.
Inspect the pad’s local settings, then its footprint settings, then the board defaults. Also check whether the opening is drawn as a separate aperture object rather than derived from the copper pad. Such geometry may not respond to the setting you are adjusting. Check both board sides independently when a footprint contains asymmetric aperture definitions or has been moved from its original mounting side.
Build a resolved-setting record
| Level | What to record |
|---|---|
| Board | Default mask and paste settings relevant to the pad |
| Footprint | Any local values and their reason |
| Pad | Explicit override or inherited behavior |
| Output | Measured final opening and layer |
Keep mask and paste decisions separate. They support different manufacturing operations, and a change justified for stencil printing does not automatically justify changing the solder-mask opening. Obtain the appropriate fabricator or assembler review for the intended modification.
Correct the narrowest responsible source
- Determine whether the local setting is intentional.
- Remove or revise an obsolete override in the controlled source.
- Update placed instances if the library changed.
- Regenerate mask and paste outputs.
- Inspect the affected family and an unaffected comparison family.
Do not assume that entering zero and leaving a field unset have identical inheritance behavior in every tool or version. Confirm the resolved result in the software being used, then document the intended setting rather than relying on a remembered interface convention.
Close the issue only after inspecting the manufacturing output. Preserve any approved aperture exception with the library object so a later cleanup does not remove it unintentionally. For population-specific paste decisions, use the separate DNP paste-output review; an inheritance correction does not determine which components belong in a build.
Move from reading to a build-ready project
Use the fabrication and assembly checklists to prepare drawings, production files and test requirements.
Open the DFM checklist