A plated hole inspected before routing is not yet the finished castellation. The board edge is created by a later operation that changes the hole’s geometry. Inspect the delivered half-hole and its surrounding material after that operation rather than relying only on earlier plating evidence.
Identify the intended final split
Show the hole center, final outline and required pads in aligned manufacturing data. State the intended remaining geometry and any agreed tolerance. A hole merely touching an outline is not a complete instruction for producing a functional castellated connection.
Eurocircuits’ castellation explanation describes plated holes cut through during routing and discusses structural support around them. Its recommendations are specific to its manufacturing route; review the selected supplier’s requirements before release.
Keep before-and-after evidence distinct
| Stage | What the evidence addresses |
|---|---|
| Plated hole | Condition of the intact hole before edge creation |
| Routed edge | Remaining wall, edge quality and final geometry |
| Finished contact | Specified surface condition for joining |
| Mounted module | Resulting connection to the host assembly |
Document which stage produced each inspection image. An intact-hole section can support plating review but does not show the physical condition created by cutting the finished edge.
Examine the functional wall
Inspect the remaining plated region and its transitions to the surface pads using the agreed acceptance criteria. Record burrs, lifted material or unusual edge conditions without assuming their cause from appearance alone.
For example, a module may pass bare-board continuity while an irregular routed edge interferes with placement on its host. Electrical continuity and mechanical seating should therefore be evaluated as separate requirements.
Retain the panel orientation and routing sequence when investigating a repeated location pattern. If the same edge position is affected across panels, this helps the fabricator connect the observation to tooling and support history.
Label repeated castellations individually in an investigation. Recording only that an edge failed discards the position information needed to compare routing entry, exit and local support around the panel.
Verify the assembled connection
Use the actual host footprint and approved soldering process for qualification. Confirm that the module can sit as intended and that the resulting joints meet the product’s requirements. Do not use extra solder as an undocumented repair for an unacceptable manufactured edge.
Consider any later finish or cleaning operation in the final inspection stage. The delivered surface, not an intermediate process sample, is the condition the assembly team receives.
Keep castellation acceptance separate from ordinary outline-burr inspection. The routed-edge guide covers general edge observations, while edge-plating sequence review addresses another construction whose route changes the exposed conductive surface.
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