The Collaboration Problem in Mechanical CAD
Traditional mechanical CAD was designed for one engineer working on one file at a time. SolidWorks, CATIA, NX — all were built on the assumption that files live on a local disk or network share and only one person edits a file at a time. PDM systems were bolted on later to manage the coordination problem, with check-in/check-out workflows that prevent simultaneous editing.
Onshape was built from scratch in 2012 as a cloud-native CAD platform, with collaboration and version control as core design principles rather than afterthoughts. The question is whether that architectural advantage translates to practical benefits that justify switching from a mature platform like SolidWorks.
Onshape Core Capabilities
Onshape uses a parametric solid modeling approach that will be familiar to SolidWorks users. Feature-based design, sketch constraints, assemblies with mates, drawings — the concepts are the same. Engineers with SolidWorks experience typically become productive in Onshape within a few weeks.
Key Onshape concepts that differ from SolidWorks:
- Document: the top-level container in Onshape. One document can contain multiple parts, assemblies, and drawings. There is no separate part file, assembly file, and drawing file — they coexist in one document.
- Part Studio: the Onshape equivalent of a SolidWorks part file. Multiple parts can be modeled in one Part Studio — closer to SolidWorks multi-body parts than assemblies.
- Version and History: built into every document. Every save creates a history entry. You can branch, merge, and restore at any point — like Git, but for CAD.
Onshape’s Built-in Version Control
This is Onshape’s strongest differentiator. Every document has a complete edit history. You can view the document at any previous state, restore to a previous version, or create a branch to explore an alternative design path without affecting the main design.
Branches can be merged — changes from a branch can be selectively integrated into the main document. This is a familiar concept for software developers but revolutionary in mechanical CAD.
Compare this to SolidWorks PDM: PDM provides revision management (version A, version B, released state) but not true branching and merging. If you want to explore a design alternative in SolidWorks, you make a copy of the file, modify it, and manually reconcile the differences — a process that does not scale.
For teams that regularly explore design alternatives and need to preserve all variants — product development teams, R&D groups — Onshape’s version control is a genuine advantage.
Collaboration Features
Multiple engineers can view the same Onshape document simultaneously. One engineer can edit a Part Studio while another works on the assembly in the same document. Changes appear to collaborators in near-real time.
Comments, follow-me mode (following another user’s viewport), and inline messaging are built into the interface — no separate communication tool required for design discussions.
This is fundamentally different from SolidWorks PDM’s check-out model, where only one engineer can have a file checked out for editing at any time.
Pricing
Onshape pricing as of 2026:
- Free plan: public documents only, limited storage
- Standard: approximately USD 1,500/year/user
- Professional: approximately USD 2,500/year/user
- Enterprise: custom pricing
SolidWorks Professional with PDM Standard: approximately USD 6,000-8,000/year/user total. On licensing cost alone, Onshape is significantly cheaper for teams that need PDM-like functionality.
Offline Limitations
Onshape is a cloud application. It requires internet connectivity. A mobile app exists for viewing documents offline, but editing requires connectivity.
This is a real operational constraint for engineers who work on factory floors with poor Wi-Fi, who travel to suppliers in areas with unreliable connectivity, or whose companies have strict internet access policies for engineering systems.
SolidWorks with a local PDM vault can operate entirely offline once files are checked out. For organizations with connectivity limitations, this is a non-trivial advantage.
Data Security Considerations
All Onshape data lives in PTC’s cloud infrastructure (AWS). For companies with intellectual property protection requirements — defense contractors, companies with export control obligations, organizations with customer confidentiality agreements — cloud storage of design data requires a legal and security review.
Onshape offers Enterprise plans with enhanced security controls, SOC 2 compliance, and options for data residency. But the fundamental architecture is cloud-hosted, and some organizations’ security policies prohibit this regardless of compliance certifications.
SolidWorks with an on-premise PDM server stores data entirely within the company’s own infrastructure. For companies where data sovereignty is non-negotiable, SolidWorks with PDM remains the only viable option of the two.
Capability Gaps
Despite strong core CAD capabilities, Onshape lags SolidWorks in some areas:
- Simulation: Onshape Simulation is limited compared to SolidWorks Simulation Professional.
- Weldments: no native Weldments workbench. Structural frame design requires workarounds.
- Drawing standards compliance: drawing tools are improving but still behind SolidWorks for complex annotation.
- Large assembly performance: similar limitations to Fusion 360 above ~500 components.
- Ecosystem: fewer third-party add-ins and custom tools compared to the mature SolidWorks ecosystem.
Who Should Consider Switching
Onshape is most compelling for:
- New companies with no existing CAD infrastructure choosing a first platform
- Teams that genuinely need collaborative real-time editing (product design agencies, rapid-iteration development teams)
- Organizations where version control and design history are critical (medical device, regulated industries where audit trails matter)
- Teams with reliable internet and no data sovereignty restrictions
Stay with SolidWorks if:
- Your team has established SolidWorks workflows and PDM
- You need on-premise data storage
- You work frequently offline or in low-connectivity environments
- You rely heavily on SolidWorks-specific add-ins (Simulation, Weldments, etc.)
Key Takeaways
- Onshape’s built-in branching/merging version control is a genuine architectural advantage over SolidWorks PDM for teams that actively explore design alternatives.
- Real-time collaborative editing in Onshape eliminates the check-out bottleneck that limits SolidWorks PDM workflows.
- Offline limitations and cloud data storage are real constraints that eliminate Onshape for some organizations.
- Onshape’s licensing cost is lower than SolidWorks Professional + PDM, but migration cost for existing SolidWorks teams is substantial.
- For a new company starting fresh with reliable connectivity and no legacy file requirements, Onshape is worth serious evaluation as a primary platform.
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