STEP Import Failing in Zoo Design Studio v1.3.5 (Desktop)

Support
1

Hi Zoo team,

I’m using Zoo Design Studio on Windows (desktop v1.3.5) and trying to import several STEP (.step/.stp) files that were exported from an external CAD system.

All of these STEP files:

  • Open correctly and show full geometry in an independent STEP viewer (BR3DViewer on Windows), so the files themselves appear valid.

  • Have reasonable sizes (including one larger assembly around 70–80 MB and several smaller subassemblies).

In Zoo Design Studio:

  • I add the STEP files to the project and see them listed under Project Files.

  • When I use Commands to insert a STEP file into main.kcl, Zoo generates an import “file.step” as aliasName line.

  • After rebuild, I see a red dot with the tooltip “import failed,” and no solids appear in the viewport—only the origin planes—even after zoom extents/fit view.

  • I’ve tried restarting, moving the STEP files from a cloud‑mapped drive to a local folder, and testing multiple STEP files; the behavior is the same.

Questions:

  1. What is the correct, recommended KCL syntax for referencing and displaying STEP files that are already in Project Files in the current desktop build?

  2. Are there known limitations or required STEP export settings (STEP AP version, solids vs. surfaces, size limits) that could cause an “import failed” message even when other viewers can open the file?

  3. If you’d like to inspect the actual STEP files, I’m happy to share them via your secure process once you send an email request, as I prefer not to post them publicly.

Thanks in advance for any guidance on getting STEP imports working in the desktop app—being able to bring these assemblies into Zoo is key to exploring design modifications.

Best,
Harley

2

Thanks a ton for the detailed write‑up and questions, Harley - this level of detail is super helpful for us and for anyone else running into similar issues.

I’m going to put together a dedicated doc that walks through STEP import in Zoo Design Studio (recommended KCL syntax, known limitations, and export best practices). Once that’s live in our docs, I’ll drop the link back here in this thread so you’ve got one place with all the answers.

Really appreciate you taking the time to lay this out so clearly.

Max

3

Please let us know if it’s helpful:

4

Appreciate the user guide on this. I did follow the process and still having issues. Per instructions here are the relevant details:

  • Zoo Design Studio version and whether you are using the desktop app or browser

    • Desktop app v1.3.5

  • operating system and version

    • Windows 11

  • the STEP file, when it can be shared

    • model is confidential prefer to share via your secure process

  • the STEP file size and source CAD system

    • 9 files ranging from 800KB to 16.7MB

    • Request sent to CAD operator for that information

  • the export settings used, if known

    • Request sent to CAD operator for that information

  • the exact KCL import line

    • @settings(kclVersion = 2.0)

    • import “FingerTendons_BallJoints_ASSY.step” as fingerTendonsBallJointsAssy

  • whether smaller STEP files import successfully in the same project

    • yes, your sample “flange.step” imported cleanly

  • screenshots or text from the error marker, if available

5

Feedback from CAD operator on CAD sources and export settings: “1. Fusion 360

2. All files were exported as a generic STEP file. No unique settings were selected.”

6

Hi. Curious if help for this is available. If not, the program is not useful to me and I will seek a refund. Was hoping to use the program to help our business but if we cannot upload STEP files not seeing much value here. Please communicate with me. thanks…

7

Hey Harley,

Thanks again for all the detail you’ve shared so far - it’s been really helpful on our side.

Our team is actively working on improving STEP import in Zoo Design Studio, especially for assemblies like the ones you’re trying to bring in.

That said, if Zoo Design Studio isn’t meeting your needs right now, you’re absolutely free to request a refund by reaching out to our support team at [email protected].

Max