A Receiving Checklist for Supplier STEP Files That Produces a Clear Decision

A useful STEP inspection ends with a decision another person can understand: proceed with the stated task, request a corrected package, or hold because a requirement is unresolved. A screenshot of a model and the words “looks fine” leave too much uncertainty for the next engineer.

This checklist is for receiving teams reviewing nominal geometry before quotation, manufacturing preparation or design review. It does not establish that a manufactured part meets its specification.

Disclosure: This guide was prepared for CADProps, a provider of CAD inspection tools. The workflow can be used with any suitable viewer and the recipient’s own CAD or CAM system.

Start with the decision you are being asked to make

Write one sentence describing the permitted next step. For example: “Check that the supplied Rev C bracket geometry is suitable for preparing a machining quotation.” That is narrower than approving the design, approving a manufacturing process or accepting delivered hardware.

Next, identify what controls the task. The package may include a STEP model, a drawing, a specification and a parts list. Ask the sender to resolve conflicting revisions or requirements. Do not choose the newest-looking filename yourself.

Keep an intake record with six fields:

  • Part or assembly identifier and revision
  • Configuration or variant
  • Exact delivered filenames and receipt date
  • Intended task and controlling documents
  • Expected included and excluded geometry
  • Reviewer and unresolved questions

A file checksum can help show that two people inspected the same bytes. It does not prove that those bytes represent the approved release.

Reopen the delivered file and record its scope

Inspect the actual export received, rather than a screenshot from the authoring system. Record warnings before dismissing them. Check whether the receiver has a part, several bodies, an assembly or only surface geometry.

Compare what loaded with an independent scope reference. If a drawing shows two inserts, ask whether they belong in the STEP or are intentionally omitted. For an assembly, keep three quantities separate: unique part definitions, placed instances and solid bodies. Different software may count them differently, so an unexplained numerical mismatch deserves investigation rather than an automatic rejection.

Use an explicit scope statement such as “housing and cover loaded; fasteners intentionally excluded by the release manifest.” Avoid “complete assembly” unless completeness has been checked against a controlled source.

STEP supports parts, assemblies and product information, but the presence of that information must be checked in the individual file. NIST’s STEP File Analyzer and Viewer provides analysis of entities, PMI and validation properties when deeper exchange-file investigation is needed.

Choose measurements that answer a question

Select a small set of anchors from the controlled definition before measuring. Useful choices include an overall part dimension, a distinctive bore and the relationship between two mounting interfaces. Explain the purpose of each check: scale, revision identification or placement.

Record the selected geometry, displayed units, result and reference value. A bounding box measures an envelope in its coordinate frame; it does not automatically represent the drawing’s dimension between particular faces. Likewise, two arbitrary points on a displayed surface may not reproduce a diameter or center distance.

If a measurement disagrees, first check the measurement definition, units, active component and configuration. Do not scale the model simply to make one number match. A scale correction can conceal the wrong source file or a translation problem.

Agree acceptance criteria appropriate to the receiving workflow. A purchasing checklist should not invent a universal geometric tolerance for every importer, component and downstream use.

Separate visual inspection from geometric checks

A shaded display answers whether the object appears plausible. It does not, by itself, establish closed-solid validity, successful translation of every feature or the presence of manufacturing requirements.

Where supported, check solid status and investigate unexpected open surfaces. Compare volume or other validation properties only when both results use the same geometry scope and units. Treat agreement as supporting evidence: two different shapes can have the same volume.

Do not silently repair the received file. Preserve the original, document the repair and ask the responsible engineer to approve any change that affects the released geometry. When an import problem appears application-specific, keep the original export available for the supplier and receiving-system support team.

Record what geometry cannot settle

Create an “outside this check” section. Depending on the task, it might include material grade, heat treatment, surface finish, thread requirements, tolerances or inspection obligations.

Some STEP workflows carry PMI, so it is inaccurate to say STEP never contains tolerances. It is equally unsafe to assume a viewer’s absence of annotations means there were none in the file. If a required manufacturing instruction is missing or unreadable, ask for the controlled drawing or a validated PMI workflow.

For a quick supported-geometry review, the CADProps STEP viewer is one option. CADProps processes uploads on servers; use an approved transfer route and check file-handling requirements before uploading confidential supplier data. Viewing geometry is not a certification or manufacturing release.

End with a specific disposition

Use one of three outcomes, qualified by the intended task:

  1. Proceed: identity, scope and agreed nominal checks are satisfied; required supporting documents are available
  2. Correct and resubmit: a defined problem prevents use, such as the wrong revision or an unexplained missing component
  3. Hold for clarification: the evidence is insufficient to decide, such as conflicting source documents or an unresolved requirement

For every exception, record the observation, its consequence, the person responsible for resolving it and the evidence needed to close it. “Bore differs from drawing; confirm controlling revision” is actionable. “File seems wrong” is not.

The receiving record should travel with the package. It lets the next team see exactly what was checked, what remains uncertain and why proceeding is justified.

 

评论

发表评论

此博客中的热门博文

When Native CAD and STEP Disagree at Supplier Handoff

The supplier can open the model, but a component is missing, the expected feature tree has disappeared or the assembly cannot be edited as intended. These problems call for different remedies. Re-exporting the same model repeatedly is unlikely to help until both sides identify what information the handoff needs to preserve. Disclosure: This guide was prepared for CADProps, which provides CAD inspection tools. It describes a practical diagnostic sequence rather than a claim that one format or viewer is always best. First separate the editable source from the exchange deliverable Ask the receiver what they need to do: quote nominal geometry, prepare CAM, modify the design or consume manufacturing annotations. Then assign a role to each delivered file. For example, a native package may be the editable collaboration source, while a STEP export is the geometry snapshot for another system. A controlled drawing may carry manufacturing requirements outside either workflow. Identify the sam...
阅读全文

Open a supplier model on a phone without installing CAD

图片
By CADProps A model question can arrive when the recipient is away from a CAD workstation. A screenshot may identify the component, but it fixes the camera at the sender's chosen angle. A browser view lets the recipient turn the model and find the feature being discussed before returning to the design conversation. This walkthrough is supplied by CADProps, the independent project behind the viewer used here. It demonstrates an initial visual review of an authorised file. It does not claim a timed phone benchmark or require a particular handset. Start with a recognisable part For practice, use bearing-housing.step from the public CAD model collection . It is a CADProps CC0 demonstration with a cylindrical bore, flange holes and mounting features. These landmarks make it easier to ask a useful question than an anonymous shape would. Figure 1. The original bearing-housing.step demonstration in an exterior view. Model and screenshot: CADProps; model licence: CC0. This saved deskt...
阅读全文