01

One measurement is not a fit envelope

Measure more than one piece of each model, including the widest body, base, rim and any handle. Record which features vary together. A maximum width paired with an unrelated maximum height is useful as an envelope, but actual samples are still needed to understand the shape. Do not infer this range from product photographs.
02

Choose where load may be carried

We would start with stable base and broad body contact, while keeping a thin rim or decorative protrusion out of the load path. A support that avoids one fragile point may create another at a narrow edge. Mark permitted and restricted contact areas on photographs before asking for an insert design.
03

Compare fixed and accommodating supports

A tight rigid opening may reject a larger piece. A folded support with controlled flexibility may accept variation, but still needs enough restraint for the smallest piece. A shaped fibre or foam support offers a different contact surface and production route. Compare these using the same measured range rather than ranking materials by touch. See the insert material comparison.
04

Check removal as well as retention

Leave access for fingers without requiring a user to lever against a handle or rim. If a liner covers the support, test the final covered form because it changes friction and cavity size. Inspect contact marks after repacking. A sample that can be loaded only by one experienced person may be unsuitable for the intended packing team.
05

Use a repeatable sample record

  • Identify each test piece and its dimensions.
  • Record the insert material and revision.
  • Check rocking, rotation, removal and lid clearance.
  • Record visible marks and unsupported features.
  • Agree transport checks for the complete packed unit.
This is a development approach, not a report of a completed customer order. The sample approval guide explains how to record the result.