Comparison of three-dimensional geometry and technical drawing requirements
The schema describes reading with geometry the conditions of production together. STEP files may also contain properly prepared PMI information; the transferred content must also be verified.

Read the model and drawing together

The STEP model makes it easier to study the three-dimensional geometry of the part and evaluate the tool access to the cutter. technical drawing collects measurements, references, surface conditions and special notes in a common document. Sending files together reduces questions that are missing in the bidding interview.

However, it is not true to say that "STEP only carries the shape". The appropriately prepared STEP AP242 files may contain product and manufacturing information (PMI). The important thing is not the file extension but the fact that the information is actually present and can be read correctly on the opposite system.

Identify the set of information based on production

Tolerances, material, surface and acceptance requirements in a drawing-based job should be clearly included in the current technical drawing. If the model-based identification is used, it must be decided by the parties which model and which PMI information will be based. Being able to open the model does not prove that all manufacturing information is transferred.

Critical measure and references Review. A piece that appears visually understandable may still be described as incomplete in terms of control.

Match part code, revision and unit

Check that the PDF and STEP file belong to the same revision. Use the part code, revision, and unit of measurement consistent. Reopen the model you export to review that there is no missing surface or unexpected scale change.

If you are sending a change, make it clear that the previous file has been replaced. If there are more than one alternative, name them separately; type which one is for bidding and which one is for production.

Don't close the conflict by guess

If dimensions or geometry differ between the model and drawing, ask the design owner to clarify rather than silently choosing one. Do not assume that the PDF always takes precedence unless a document hierarchy has been agreed. Issue an updated document set after clarification.

Add the quantity, material status and delivery expectation next to the files. Proposal preparation guide You can complete your request with your documents You can forward to FactorAB.

Technical source

NIST STEP and product/production information (PMI)

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