Planes and Through Hole Pins

Typical designs have through hole pins for headers and connectors.

What is often overlooked is additional clearance needed to create the specified finished hole size (FHS) for pins that pass through the planes.

Design rules can be used to increase the anti-pad (copper clearance) that surrounds each pin that passes through a plane.

Example feedback from PCB fabricator:

The 43 mil holes are drilled at 47.2 mil and 59 mil holes are drilled at 63 mil to achieve the specified finished hole size after plating. After drilling the holes are 6 mils away from copper.  
Can we increase the hole edge to copper spacing to prevent CAF issue ?

Problem:

The design is using a global minimum Plane Clearance rule (8mil).

The global minimum of 8 mils is adequate for small vias and tracks. However additional clearance is needed for through hole pins to prevent Conductive Anodic Filaments (CAF).

Solution:

Use design rules to increase the copper clearances for pins that pass through plane layers.

Through hole pins with 12 mil clearance.

That's It !