Start from the active bend zone
Overlay the defined bend geometry on every conductor layer. Identify traces that enter, leave, or turn inside the moving span, including return paths that may not be obvious in a signal-only view. Use the actual mechanism positions rather than one centerline marker if the bend migrates during operation.
Routing features to inspect
| Review item | Design question | Evidence or action |
|---|---|---|
| Turns | Does direction change where curvature is greatest? | Mark the feature on the motion overlay |
| Width changes | Is a narrow section carrying local load or current? | Review electrical and mechanical needs together |
| Interconnects | Can a via or pad move into support? | Document any remaining loaded feature |
| Reference copper | Will a routing revision interrupt the return path? | Review the complete layer set |
Review transitions as individual features
Examine neckdowns, pad entries, branches, and layer transitions in the loaded region. Ask whether each can move into a supported area without creating another packaging problem. Coordinate pad transitions and vias with the mechanical review. Smooth routing is a useful design objective, but a decorative teardrop or curved trace does not by itself qualify the assembly.
Protect electrical requirements while simplifying the path
Maintain the signal’s required reference and spacing when changing conductor geometry. If removing copper helps a mechanical concept, evaluate the electrical consequence with the owner of that net. Compare candidate routes in a representative build using a controlled change record. Retain failed samples and their layer locations; this is more informative than repeatedly redrawing a bend without a hypothesis.
Before you release the design
- Overlay the entire motion envelope before final routing.
- Inspect all copper layers, including fills and unused pads.
- Name critical conductors for electrical monitoring during tests.
- Recheck fabrication outputs after route and coverlay changes.
Watch points
- Do not mistake one preferred routing pattern for a universal fatigue rule.
Practical questions
Should traces always be straight through a bend?
A simple path can make the mechanical intent easier to control, but the appropriate geometry depends on the motion and electrical constraints. Review the actual route and test the complete construction.
Can routing changes fix every cracked trace?
No. Investigate support edges, material, processing, handling, and the motion path. Routing may be one contributor, and changing it without examining the failure can conceal the cause.
Technical references
References support the material or design context. Check the exact grade, part number, document revision and project conditions before release.Updated 27 September 2026 · Technical content policy · Engineering guidance supports project review; the agreed drawing defines the build.