Understanding the CAD Viewer

Understanding the CAD Viewer

What is the CAD Viewer?

• View 3D CAD models without native CAD software

• Navigate assemblies and inspect components

• Measure dimensions and angles

• Compare different versions visually (CAD diffing)

• Annotate and markup designs

• Share views with team members

Supported File Formats

Native CAD Formats

• .sldprt (parts)

• .sldasm (assemblies)

• .slddrw (drawings)

• .ipt (parts)

• .iam (assemblies)

• .idw (drawings)

• .f3d (Fusion files)

• .CATPart (parts)

• .CATProduct (assemblies)

• .prt (parts)

• .asm (assemblies)

• .prt (parts)

• .par (parts)

• .asm (assemblies)

Neutral Formats

• Industry-standard exchange format

• Preserves 3D geometry

• Most widely supported

• Older exchange format

• Widely compatible

• 3D printing format

• Surface mesh representation

• 3D mesh format

• Textures and materials

• High-quality geometry kernel format

2D Formats

• Engineering drawings

• Documentation

• AutoCAD drawings

• 2D exchange format

Other Formats

• JT (.jt) - Lightweight visualization

• 3DXML - Dassault Systèmes format

• glTF (.gltf, .glb) - Web 3D format

• And many more...

Viewer Capabilities

1. 3D Navigation

• Rotate: Click and drag to rotate the model

• Pan: Right-click and drag (or Shift + drag) to pan

• Zoom: Scroll wheel to zoom in/out

• Fit to View: Double-click to fit entire model in view

• Located in top-right corner

• Click faces for standard views (Front, Top, Right, etc.)

• Click edges for isometric views

• Click corners for trimetric views

• Home button returns to default view

• Perspective: Realistic view with depth perception

• Orthographic: No perspective distortion (engineering view)

• Wireframe: Show only edges

• Shaded: Solid surfaces with lighting

• Shaded with Edges: Combination view (most common)

2. Assembly Navigation

• Hierarchical view of all components

• Expand/collapse subassemblies

• Click components to highlight in 3D view

• Show/hide individual components

• Click components in 3D view to select

• Selected components highlight in tree

• Multi-select with Ctrl/Cmd + click

• Show/hide components individually

• Isolate specific components

• Show only selected components

• Restore all visibility

• View assembly in exploded state

• Understand component relationships

• See internal parts

3. Measurement Tools

• Measure between two points

• Measure between faces, edges, or vertices

• Results shown in model units

• Measurements persist in view

• Measure angles between faces or edges

• Results in degrees

• Useful for verifying design intent

• Measure circular features

• Identify hole sizes

• Verify fillet radii

• Measure surface areas

• Calculate material requirements

• Show X, Y, Z coordinates

• Reference to model origin

4. Section Views

• Cut through model to see internal features

• Position section plane anywhere

• Rotate section plane to any angle

• Multiple section planes possible

• Define a box to show only interior

• Useful for complex assemblies

• Adjust box size and position

• Inspect internal features

• Verify wall thicknesses

• Check clearances

• Understand internal assembly

5. CAD Diffing (Version Comparison)

• Compare two versions of the same file

• See what geometry changed

• Identify added, removed, or modified features

• View both versions simultaneously

• Synchronized navigation

• Easy to spot differences

• Superimpose versions with transparency

• Color-coded differences

• See exact geometric changes

• Green: Added geometry

• Red: Removed geometry

• Yellow/Orange: Modified geometry

• Gray: Unchanged geometry

• Design reviews

• ECO verification

• Change identification

• Troubleshooting issues

6. Annotations

• Comment Panel: Open the annotations panel from the left toolbar to view or manage discussion threads.

• Pinned Notes: Comments are attached to specific parts of the model for precise context.

• Threaded Discussions: Each annotation supports replies for focused collaboration.
• @Mentions: Tag teammates to notify them directly in the thread.
• Attachments: Add supporting PDFs or images to provide additional context.

• Version-Scoped: All annotations remain linked to the version they were created on.

• All annotations stay linked to the model version where they were created.

• Tagged users receive in-app notifications.

• Annotations can be resolved or unresolved for review cycles.

7. Properties and Metadata

• File name and format

• File size

• Upload date and contributor

• Current revision

• Material

• Mass

• Center of gravity

• Surface area

• Volume

• Part number

• Description

• Designer

• Approval status

• Any custom fields from CAD system

When to Use the CAD Viewer

✅ Use the Viewer For:

• Review designs without opening CAD software

• Stakeholders can participate without CAD licenses

• Measure and verify dimensions

• Check for obvious issues

• Show designs to clients in browser

• No software installation required

• Clients can explore models themselves

• Professional presentation

• Manufacturing partners can inspect designs

• Verify producibility

• Measure critical dimensions

• Identify potential issues

• Use CAD diff to see what changed

• Verify ECO implementation

• Confirm changes match description

• Identify unintended changes

• Check file before downloading

• Verify correct file was uploaded

• Spot-check dimensions

• Confirm assembly structure

• Discuss designs in meetings

• Point out specific features

• Get feedback from non-CAD users

• Share views with team

❌ Don't Use the Viewer For:

• Viewer is read-only

• Cannot modify geometry

• Cannot change parameters

• Cannot save changes

• No FEA or simulation

• No interference checking

• No mass properties calculation (beyond what's embedded)

• No drawing creation

• No GD&T analysis

• No tolerance stack-up

• No surface analysis

• Limited measurement types

Viewer Interface

Main Viewing Area

• Central area showing the model

• Interactive 3D manipulation

• Context-sensitive cursor

• Selection highlighting

• Gradient or solid background

• Adjustable for contrast

• Professional appearance

Navigation Cube

• Standard view selection (Front, Top, Right, Back, Bottom, Left)

• Isometric views (click edges)

• Trimetric views (click corners)

• Home button (reset to default view)

Toolbar

• Select: Pick components or features

• Measure: Distance, angle, radius tools

• Section: Create section views

• Explode: Show exploded assembly view (if available)

• Wireframe/Shaded: Toggle display modes

• Fit: Fit model to view

• Home: Reset view

Assembly Tree Panel

• Hierarchical component list

• Part names

• Visibility toggles (eye icons)

• Selection indicators

• Navigate complex assemblies

• Show/hide components

• Select components

• Understand structure

Properties Panel

• File metadata

• Model properties

• Measurement results

• Selected component info

• View file information

• Check properties

• See measurement values

• Inspect component details

CAD Diffing in Detail

What is CAD Diffing?

Why CAD Diffing is Valuable

• Quickly see what changed between revisions

• Verify ECO implementation

• Catch unintended changes

• Confirm changes match ECO description

• Identify scope creep

• Validate modifications

• Find when a problem was introduced

• Compare working vs. broken versions

• Identify root cause of issues

• Show stakeholders exactly what changed

• Visual proof of modifications

• Clear documentation

How to Use CAD Diff

• Open a file in the viewer

• Choose "Compare Versions" or similar option

• Select two versions to compare (by commit hash or revision)

• Side-by-side for overview

• Overlay for precise comparison

• Color-coded for detailed analysis

• Rotate and zoom to examine changes

• Use section views to see internal changes

• Measure changed features

Interpreting Diff Colors

• New geometry not in old version

• Added features

• New components in assembly

• Geometry present in old version but not new

• Deleted features

• Removed components

• Geometry that changed shape or position

• Resized features

• Moved components

• Identical geometry in both versions

• No modifications

• Reference for context

Diff Limitations

• Very small changes may be hard to see

• Use measurement tools to verify

• Zoom in for detail

• Changes inside solid bodies may not be visible

• Use section views to inspect

• Check properties for mass changes

• Viewer shows geometric result, not parametric changes

• Can't see which features were edited

• Can't see parameter value changes

Viewer Best Practices

For Reviewers

• Start with overall view

• Zoom into areas of interest

• Use section views for internal features

• Measure critical dimensions

• Navigate complex assemblies systematically

• Hide components to reduce clutter

• Isolate areas of interest

• Add annotations to specific features

• Write clear comments

• Reference measurements in feedback

For Designers

• Ensure files are contributed and up-to-date

• Add descriptive contribution messages

• Link to related documentation

• Address annotated issues

• Reference specific comments in contributions

• Use diff to show changes made

For Project Managers

• Check recent contributions visually

• Verify work is progressing

• Spot-check quality

• Share viewer links in meetings

• Use viewer for presentations

• Enable stakeholder participation

Viewer vs. Native CAD Software

When Viewer is Sufficient

When Native CAD is Required

Viewer Advantages

• Works in any modern browser

• No software to install or maintain

• No license costs for reviewers

• Anyone with project access can view

• Works on any device (desktop, tablet)

• Platform-independent (Windows, Mac, Linux)

• View latest version immediately

• No need to download and open files

• Automatic format support updates

• Easy to share views

• Annotations and comments integrated

• Version comparison built-in

Technical Requirements

Browser Compatibility

• Chrome (recommended)

• Firefox

• Safari

• Edge

• Modern browser (last 2 versions)

• JavaScript enabled

• WebGL support (for 3D rendering)

Performance Considerations

• Small files (< 10 MB): Instant loading

• Medium files (10-50 MB): Few seconds

• Large files (50-200 MB): May take 10-30 seconds

• Very large files (> 200 MB): May be slow or require optimization

• Simple parts: Excellent performance

• Assemblies (< 100 parts): Good performance

• Large assemblies (100-1000 parts): Acceptable performance

• Huge assemblies (> 1000 parts): May be slow, consider simplification

• Use STEP or JT for large assemblies (lighter than native formats)

• Simplify assemblies if possible

• Hide unnecessary components

• Use lightweight representations if available

Common Use Cases

Use Case 1: Client Design Review

1. Invite clients as Workspace Members and assign with Viewer roles for the relevant projects.

2. Client opens file in browser (no CAD software needed)

3. Client navigates model, measures features

4. Client adds comments and attachments under ECOs.

5. Designer addresses feedback

6. Client approves or requests changes

Use Case 2: Manufacturing Feasibility Review

1. Share project with manufacturing partner (Project Viewer)

2. Partner inspects geometry in viewer

3. Partner measures critical dimensions

4. Partner uses section views to check wall thicknesses

5. Partner comments on potential issues

6. Designer modifies based on feedback

Use Case 3: ECO Verification

1. ECO describes required changes

2. Designer implements changes and contributes

3. Reviewer opens CAD diff comparing before/after

4. Reviewer verifies changes match ECO

5. Reviewer approves or requests corrections

6. ECO closed with diff documentation

Use Case 4: Team Design Review Meeting

1. Open viewer in meeting (screen share)

2. Navigate through design together

3. Team members point out concerns

4. Measure dimensions collaboratively

5. Assign action items based on findings

Troubleshooting

Problem: File Won't Load

• File format not supported

• File corrupted

• File too large

• Browser compatibility issue

• Check file format against supported list

• Try different browser

• Re-upload file

• Simplify assembly or convert to STEP

Problem: Slow Performance

• Large file size

• Complex assembly

• Many components

• Slow internet connection

• Hide unnecessary components

• Use lighter file format (STEP, JT)

• Simplify assembly

• Upgrade internet connection

Problem: Measurements Don't Match CAD

• Unit conversion issue

• Measurement tool limitation

• File conversion accuracy

• Viewer precision limits

• Check units in viewer

• Verify measurements in native CAD

• Use neutral format (STEP) for better accuracy

• For critical dimensions, verify in CAD software

Problem: Can't See Internal Features

• Solid body blocking view

• Section view not enabled

• Component hidden

• Use section view tools

• Hide external components

• Use transparency (if available)

• Check assembly tree for hidden components

Quick Reference

Viewer Capabilities

Related Articles

• Multi-CAD Compatibility

• How to Compare File Versions (CAD Diffing)

• Understanding Version Control in CAD ROOMS

• How to Upload and Manage Files

• How to View Version History