Bambu Lab tolerances, dimensional accuracy and part fit

Separate the four questions

A clean STL or measured bounding box does not establish tolerance or assembly fit. Current preflight supplies bounded geometry observations; it does not measure every wall, internal bore, mating surface or expected physical deviation.

A nominal clearance your agent can check

Our free enclosure example uses a 56.0 mm cavity and a 55.4 mm lid lip. These are example design dimensions, not a recommended allowance for every part:

Total nominal gap = 56.0 − 55.4 = 0.6 mm
Nominal gap per side, when centered = 0.6 / 2 = 0.3 mm

Minimum total gap =
  (nominal cavity − cavity undersize allowance)
  − (nominal lip + lip oversize allowance)

Without verified allowances for both features, the minimum physical gap is unknown. A negative result indicates possible interference. A positive result alone still does not establish fit when shape, corners, alignment and surface condition also matter.

A useful readback is: “The CAD has 0.3 mm nominal clearance per side. Applicable manufacturing variation and physical fit remain unverified.” The example includes a local geometry verifier but no physically tested sample.

Describe the inspection you need

Name critical features and provide a dimensioned drawing or its reference in the original request notes. Do not rely on a tolerance hidden in a CAD screenshot.

Critical feature: named hole, slot, lip or mating face
Nominal dimension / units: approved value
Allowed minimum / maximum: required limits
Mating part: dimensions and revision or supplied reference
Required fit: removable, sliding, retained or other behavior
Measurement location and condition: where and how to check
Intended use: actual load, temperature and environment
If the requirement cannot be met: ask before changing the design

These are requirements, not measurements already performed. Review may need a mating sample, clearer drawing or revised design. “Provider standard” is not agreement to an unstated tight tolerance.

Carry the requirement into the exact offer

1. Get the customer’s dimensions, units and tolerance before uploading. Preserve them in notes, which stays in the immutable intake.
2. Pin exact material, grade, finish and manufacturing settings. Use the documented specified policy when settings are specified; do not blindly copy the provider-standard example.
3. Request a free dfm_review about the named feature and intended fit. Advisory review does not certify the part.
4. Before accept_order_offer, match CAD/specification fingerprints and confirm the offer addresses the requirement. A missing commitment remains unresolved.

Changing material, grade, orientation requirements or geometry needs a corresponding review. No substitution preserves a tolerance by default. Follow the complete agent ordering workflow.