> ## Documentation Index
> Fetch the complete documentation index at: https://docs.3dpreppro.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Frequently asked questions

> Quick answers to common questions about 3D Prep Pro

## Uploading

<AccordionGroup>
  <Accordion title="What file formats can I upload?">
    3D Prep Pro supports OBJ, STL, 3MF, FBX, PLY, GLTF/GLB, VRM, WRL, DICOM (.dcm/.dicom), and LAS/LAZ. You can also upload ZIP, RAR, and TAR (.tar, .tar.gz, .tgz) archives — we automatically extract the 3D files inside. See [Supported formats](/models/supported-formats) for full details.
  </Accordion>

  <Accordion title="What's the maximum file size?">
    Models can have up to 8 million polygons. There's no strict file size limit, but very large files may take longer to upload and process.
  </Accordion>

  <Accordion title="Can I upload multiple files at once?">
    Yes. Drag multiple files onto the upload area, or select multiple files when browsing. Each file is processed independently.
  </Accordion>

  <Accordion title="What happens to my uploaded files?">
    Your files are stored securely on our servers. You can download your originals at any time from the model detail page. Deleting a model permanently removes all associated files.
  </Accordion>

  <Accordion title="Do I need to include texture files?">
    For OBJ files, include the .mtl file and all texture images (PNG, JPG) in a ZIP archive. For GLB and 3MF, textures are embedded in the file. For STL and PLY, no textures are needed.
  </Accordion>
</AccordionGroup>

## Repairing

<AccordionGroup>
  <Accordion title="How long does a repair take?">
    Typically 30 seconds to 5 minutes, depending on model complexity. Repair quality is automatic (always maximum detail), so there's nothing to configure. DICOM scans take longer the more segments you select.
  </Accordion>

  <Accordion title="What does repair actually fix?">
    The repair process fills holes, thickens thin walls, seals the model surface, removes floating debris, and optimizes geometry — all while preserving colors and textures. See [How repair works](/repair/overview) for details.
  </Accordion>

  <Accordion title="Can I repair the same model multiple times?">
    Yes. Each repair creates a new result without modifying your original. You can repair with different settings as many times as you want.
  </Accordion>

  <Accordion title="What if the repair fails?">
    Try a different model type preset, adjust the Custom Settings and re-run with **Re-Repair**, or check if your original file is corrupted. See [Troubleshooting](/help/troubleshooting) for more help.
  </Accordion>

  <Accordion title="Does repair change my model's appearance?">
    The repair process preserves colors, textures, and visual appearance as much as possible. Minor geometry changes may occur where fixes were applied. Use the before/after comparison to see exactly what changed.
  </Accordion>
</AccordionGroup>

## Editor and tools

<AccordionGroup>
  <Accordion title="Do I need to repair before using editor tools?">
    Some interactive tools (like Cut and Lattice) work best on repaired models. Inspection tools (like Validate and Object Info) work on any model. Tools that require repair appear dimmed until your model is repaired.
  </Accordion>

  <Accordion title="Can I undo a tool operation?">
    Tool operations create new results — your previous model version is always preserved. You can go back to the model detail page and start from any previous version.
  </Accordion>
</AccordionGroup>

## Billing

<AccordionGroup>
  <Accordion title="How many free repairs do I get?">
    Every account gets 2 free repairs with no credit card required.
  </Accordion>

  <Accordion title="Can I cancel my subscription?">
    Yes, at any time from Account Settings. You keep access until the end of your current billing period.
  </Accordion>

  <Accordion title="What happens to my models if I cancel?">
    Your models and repair history are preserved. You can still view and download them. You just can't run new repairs beyond the free tier limit.
  </Accordion>

  <Accordion title="What's the difference between the Standard and Mimaki plans?">
    Both plans cost \$60/month with the same features. The Mimaki Owner plan is for verified Mimaki 3D printer owners — verify your printer serial under Account Settings › Mimaki printer ownership (pending Mimaki admin approval). See [Mimaki printer owners](/account/mimaki-owners).
  </Accordion>

  <Accordion title="Where can I find my invoices?">
    Open **Billing History** in Account Settings and use the **Receipt** link next to any charge to download it.
  </Accordion>
</AccordionGroup>