Describe the separated leaves

Give each leaf an identifier and show its copper, dielectric, and protection layers. State whether spacing is maintained by a physical feature or simply results from the installed geometry. Do not draw a uniform gap and assume it stays uniform in motion. The selective-bonding guide explains the associated bonded-region definition.

Air-gap construction review

Stack featureSpecifyEngineering question
Individual leafComplete local stack and outlineElectrical and mechanical role
SpaceInstalled and moving envelopeClearance and interference
TerminationBonded or supported end constructionLoad transfer and alignment
HandlingLeaf sequence and assembly pathRepeatable installation

Evaluate the full travel envelope

Check each leaf at installation and at the extremes of any service movement. Review slack, contact with nearby parts, twisting, leaf-to-leaf interaction, and routing order. Use the mechanical model to communicate the envelope, but include physical samples where the model cannot reliably represent contact or sliding. Keep assembly orientation visible on the drawing.

Define how the leaves reunite

Show the transition into a common bonded, supported, or connected region. Identify which features transfer loads and how the leaves are aligned during manufacture and assembly. Ask the fabricator to propose a reviewable process and inspection plan before detailed layout is frozen. Qualify the installed construction rather than assuming separated leaves automatically provide a particular motion life.

Before you release the design

  • Name and section every leaf.
  • Distinguish controlled spacing from free separation.
  • Review all motion extremes.
  • Define the end transitions.
  • Include realistic restraints in prototype tests.

Watch points

  • A nominal air-gap dimension is ambiguous unless its measurement condition and spacing mechanism are defined.

Practical questions

Can the gap change during use?

It may, depending on restraints and motion. State whether spacing is a controlled requirement or only an illustrative installed geometry.

Does an air gap guarantee easier bending?

Do not make that guarantee from the label. Review the individual leaves, their interaction, end constraints, and actual product duty.

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.