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STEP viewer & review

Open 3D STEP models in the browser, invite your customer to review the part together, read PMI, and generate documentation from the model.

CUTL opens full 3D STEP models straight in the browser, so you and your customer can look at the same part together without anyone installing CAD. Rotate it, zoom in, pin a comment on the exact face that worries you, and agree on the part while you talk. When everyone is happy, the same model goes straight to quoting, with no exported screenshots and no long email threads.

The viewer also carries a built-in assistant, "Documentation from a 3D model", that turns an assembly into a finished parts document. Both features share the same 3D model you already uploaded, so nothing is drawn or entered twice.

Where to find it
The viewer opens whenever you add a STEP part in a project, a quick draft, or a shared upload page at app.cutl.online. No separate app, plugin, or CAD seat is needed.

Open a STEP model

CUTL reads STEP files (.step and .stp) as native 3D input. It detects a STEP file by its content, so a renamed file is still handled as a 3D model.

01
Upload the file
Drop a .step or .stp file into any upload area: a project, a quick calculation, or a shared upload page a customer sends you.
02
Model opens in 3D
CUTL renders the part in the browser. Rotate and zoom with the mouse or keyboard, and switch to full screen to inspect detail.
03
Check before you quote
Confirm the geometry, dimensions, and part tree look right, then move on to review or costing.
Single parts versus assemblies
For costing, CUTL analyses one part per file: a tube, profile, or bent sheet-metal part. The collaborative viewer and the documentation assistant, however, open full multi-body assemblies so you can walk the whole component tree. See Preparing files for how individual STEP parts are costed.

Review together

Reviewing a part in CUTL is a shared session, not a static image. You invite the customer, and both of you drive the same live model.

Invite the customer in one click

Share a link and the customer opens the identical 3D model in their own browser. There is no CAD to buy, nothing to install, and no account hoops to clear before they can look.

Discuss right on the model

Drop pins and comments on any face or edge. Each pin stays attached to the geometry it marks, so "this radius" or "this hole" is never ambiguous. Comments appear in real time for everyone in the session.

Open full assemblies, not just parts

Multi-body STEP assemblies open with their component tree intact. You can:

ActionWhat it does
Browse the treeWalk the assembly structure component by component.
IsolateFocus on one part and mute everything around it.
HideRemove parts from view to reach what sits behind them.
ExplodeSpread the assembly apart to see how it fits together.

Read PMI and metadata

When the STEP file carries product manufacturing information (PMI), CUTL reads it: dimensions, tolerances, surface finish, and datums. You review the maker's own callouts instead of re-measuring the model by hand. PMI travels in AP242 files, and only when the exporting CAD system was set to include 3D annotations, so enable annotation export in SOLIDWORKS, NX or Creo if you want the callouts to come through. Older AP203 and AP214 exports carry little or none.

Everyone sees the same view

As you rotate and zoom the model, the customer's screen follows. The live shared view keeps both sides pointed at the same feature, which is what turns a review into a decision rather than a description.

Why this replaces screenshots
A static image freezes one angle and loses the metadata. A live STEP session keeps the full geometry, the PMI, and the assembly tree in front of both people at once, so questions get answered on the spot.

Documentation from a 3D model

Inside the viewer sits an assistant that turns a 3D assembly into a finished document. It is one of CUTL's AI agents: it reads everything the file already knows, asks only for what is missing, and produces a parts document in your company template.

It reads the model for you

The assistant breaks the assembly into parts and pulls what the STEP file already carries:

  • Part names, materials, thickness, sizes, and quantities.
  • PMI dimensions and tolerances, which flow into each part card automatically.

You do not retype values that are already in the model.

It asks only what is missing

Whatever the file cannot answer, the assistant asks in a few short questions. It is careful about your time:

01
Group repeats
Identical parts are grouped, so a repeated part is asked about once, not once per copy.
02
Short questions only
You answer a handful of gaps, and you can skip any question you do not want to fill.
03
Build the document
The assistant assembles a parts list and a page per part in your template.

What you get

The output is a structured document, ready to send, archive, or edit:

SectionContents
CoverGeneral view of the assembly plus the full parts list.
Part pagesOne page per part, with the values and PMI pulled from the model.
FormatPDF to send as is, or an editable DOCX to open in Word.
What is editable, what is locked
Values pulled from the model (dimensions, tolerances, materials read from the STEP file) are locked so the document stays true to the part. The description text on each part page stays editable, so you can add notes or house wording.

For more on the assistant and the rest of CUTL's helpers, see AI agents & bots.

From review to quote

Because the review, the documentation assistant, and costing all run on the same uploaded model, there is no handoff gap. Once the part is agreed, send it straight to quoting with no re-drawing and no re-uploading.

01
Agree on the part
Finish the live review with pins resolved and PMI confirmed.
02
Send to quoting
The same STEP model flows into costing: material, cutting, and configured operations apply.
03
Into the quote
The part joins the project total and the quote alongside your DXF parts.

STEP parts are costed the same way as any other part: tubes and profiles per metre, flat and bent sheet-metal parts by unfolded area. The mechanics of that are covered in Preparing files and Quoting and cost.

Nesting needs a flat outline
A STEP part prices and quotes normally, but nesting works on flat cut outlines. To nest a STEP part or run it through a production shift, provide its flat-pattern DXF as well.

Do

  • Share the viewer link so the customer sees the live model, the PMI and the pins.

Avoid

  • Exporting a screenshot and emailing it for sign-off: you lose the 3D geometry, the PMI and the live pins, and the agreed part cannot flow into quoting without being re-entered.

Next, see Preparing files to learn exactly how a STEP part becomes a costed, quotable line item.

Ready to try it on your own parts?

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