Stop Emailing CAD Files: Why Pixel-Based Sharing is Better

Illustration of file sharing problems: size limits, version mismatch, IP risk

"I have a 280MB STEP file and need to get it under 20MB to email it." Sound familiar?

Engineers post this complaint constantly. The reality: CAD files are too large for email, too risky for Dropbox, and too hard for most recipients to actually open.

The Problem with Emailing CAD Files

Problem 1: File Size Limits

Gmail caps attachments at 25MB. Outlook at 20MB. Your assembly is 300MB. Now you're zipping, splitting, using WeTransfer, and hoping it arrives intact.

Problem 2: Software Compatibility

You're on SolidWorks 2024. Your supplier runs SolidWorks 2019. They can't open native files. You export to STEP, lose assembly structure, and half the mates break.

Problem 3: Recipient Can't Open Anything

Your CEO, investor, or sales lead doesn't have CAD software. They see a mysterious file icon. They ask you to "just show them" on a call.

Problem 4: IP Risk

Once the file is downloaded, you've lost control. They can forward it. They can modify it. They can reverse-engineer it. Forever.

Common Workarounds (And Why They Fail)

Workaround	Issues
ZIP and split files	Recipient can't reassemble; corrupt archives common
Dropbox/Google Drive link	No expiration by default; files can be downloaded and forwarded
WeTransfer	Links expire, but no access control; anyone with link can download
Export as OBJ/STL	Loses NURBS precision; still a downloadable 3D file
Render + email screenshots	Works, but static—can't rotate, zoom, or interact

The Solution: Pixels, Not Files

Instead of sending geometry, send a view:

Upload your CAD to a cloud viewer
Generate a shareable link
Recipient views in their browser—fully interactive 3D
They see rendered pixels, not vertex data
Nothing to download. Nothing to extract. Nothing to forward.

What the Recipient Experiences

Click link → browser opens
3D model loads in seconds
Orbit, zoom, pan with mouse
Looks photorealistic (studio lighting, materials)
Can leave comments by clicking on features

What the Recipient Can't Do

Download any 3D format (STEP, OBJ, STL)
Extract dimensions from the viewport
Forward the geometry to a competitor
Import into their own CAD system

When to Use Pixel Sharing vs. File Sharing

Scenario	Recommendation
RFQ to potential supplier (pre-NDA)	Pixel link only
DFM review with CM (under NDA)	Pixel link for review; STEP after approval
Investor demo	Pixel link (interactive)
Internal design review	Pixel link or direct CAD if same platform
Tooling shop needs to machine	STEP file required (they need geometry)
Customer sneak peek	Pixel link with expiration

Security Features to Look For

Not all 3D viewers are equally secure. Check for:

No download button: Obvious, but some viewers have "Export OBJ" hidden in menus
Link expiration: Set a 7-30 day limit; revoke access when project ends
View tracking: See who opened the link, when, and for how long
Password protection: Extra layer for sensitive projects
Watermarking: If they screenshot, you can trace the leak source

Key Takeaways

• CAD files are too large, too complex, and too risky to email
• Cloud viewers deliver fully interactive 3D via browser link
• Recipients see pixels, not geometry—nothing to extract
• Use pixel links for review; reserve file transfer for contracted vendors

FAQ

What if someone screen-records the viewer?

They get video pixels, not 3D data. Reconstructing a precise NURBS model from video is impractical for anything beyond trivial shapes.

Can I share assemblies with moving parts?

Yes—exploded views and animations work. The recipient sees the motion as rendered frames, not kinematic data.

Is this better than a 3D PDF?

3D PDFs embed mesh data that can be extracted. Pixel-based viewers are strictly view-only.

Stop compressing. Start sharing.

Share Securely