Hi everyone,
I’m running into a puzzling clearance issue in KiCad 8.0. Here’s what I’ve observed:
- Default Design-Rule Clearance:
- In Setup → Design Rules → Net Classes, I’ve set the Default clearance to 0.12 mm (with 0.12 mm track width, 0.3 mm via size, 0.15 mm via drill).
- Copper Zone Behavior:
- I pour a GND copper zone on F.Cu, and it seems to maintain only 0.06 mm clearance from nearby F.Cu tracks (see screenshot below).
- Manually measuring with the ruler widget confirms a 0.06 mm gap.
- Custom Footprint-Specific Rule:
- I created a push-rule to enforce 0.07 mm clearance for certain BGA-fan-out footprints, hoping to isolate that requirement.
- Instead, it appears to apply globally to all copper-zone versus trace clearances.
- DRC Results:
- Standard DRC reports any track-to-track or via-to-track clearance violations under 0.12 mm as expected.
- However, no DRC error is flagged for GND-zone-to-track clearance violations (even when the gap is only 0.06 mm).
- Questions:
- Is there a zone-specific clearance setting (e.g. in the zone properties) that overrides the net-class clearance?
- Could my custom footprint rule be unintentionally overriding the default for all zones?
- Why doesn’t the DRC complain about ground-plane gaps, even though the inspection ruler shows 0.06 mm?
- Is this a known bug in KiCad 8.0, or should I consider upgrading to a newer version?
Any insight, tips on where to look in the settings, or confirmation if this is a bug would be hugely appreciated!
