“Extra Large” CAD Models – What It Means for SolidWorks, CATIA, and Siemens NX

Dealing with crashes, delays, and lag from a massive CAD model can really derail your progress. The good news is that there are some ways to help reduce model sizes, deal with the slowdowns, and avoid them altogether.

Our CAD experts at CAD/CAM Services have been using CAD programs for decades, and we know how to work with “extra large” CAD models without missing deadlines. In this guide, we’ll give you a few helpful tips and definitions, and we’ll show you how CAD/CAM Services can handle your biggest and most complicated CAD files without any problems.

When Does a CAD Model Become “Extra Large”?

A CAD model becomes “extra large” at different points, based on the CAD program and what type of models you’re dealing with. No, we’re not talking about the actual dimension of your model or assembly, we’re talking about how much space and resources your computer has to use to open and manipulate the files.

Whenever you save or open a CAD model, you’ll be able to see how big the file is. It’s normal for 3D CAD files to be a few MB (megabytes, or 1 million bytes) large, but they can become multiple GB (gigabytes, or 1 billion bytes) as components get more complicated and assemblies gain more parts.

For assemblies, the model can become extra-large if you have too many components, the components have too much detail, or you’re adding a lot of additional conditional constraints and visual details.

For components, the size of the file has to do with how many features are used in the feature tree, visual details, and any parametric features like functions or formulas that determine dimensions.

CAD programs don’t have a specific cut-off when a model becomes too large, it depends on a number of factors which we’ll discuss later.

The Common Symptoms of “Too Large”

What’s the big deal with having big models? The short answer is “lag and latency”. Your computer will struggle to open and manipulate CAD files that are too large, and you’ll routinely encounter lag, slow-downs, and crashes.

Something as simple as rotating a model that’s too large could lock up your computer for multiple minutes.

A model that’s too large will also slow down other functions within your CAD program, such as running finite element analysis (FEA) simulations, adding constraints, moving components, renaming and saving files, and creating manufacturing drawings. Almost every aspect of your CAD program will slow down as your files get larger.

Hardware and Network Considerations

A big factor when it comes to the “extra large” cutoff for files is how powerful your computer and network are. Your computer’s RAM, CPU, GPU, and hard-drive write/read speed will directly impact how big of a file you can handle. A more powerful setup can handle larger files with less slowdown.

Of course, even the most powerful rig will run into issues if your assembly file is too massive.

If your company uses server-based licenses for CAD programs, you will also be limited by your network speed. Opening, saving, and doing certain commands in your CAD program will need to communicate with your company’s server before you can do the operation. Remote workers or people working in an office with slow network speed will notice lag during these operations, and it only gets worse as your files get bigger.

If you outsource SolidWorks CAD work, then you’re relying on your chosen company’s hardware power. At CAD/CAM Services, we went a little overboard and built incredibly powerful computers that have the specs to handle your biggest files.

SolidWorks: Handling Large Assemblies with Lightweight Modes

Since CAD programs have been around for decades, some of the major players have come up with clever ways to deal with massive assemblies and components.

In SolidWorks specifically, they offer “Large Assembly” and “Lightweight Component” modes which both help shrink down file size. These assemblies will simplify parts and simplify how parts are visually represented. You have less functionality in this setting, but it allows you to do a lot of common commands like moving around models and manipulating them.

With Lightweight Component mode, your parts get partially loaded into assemblies. You can still see everything, but you can’t adjust part features, run simulations, or change dimensions.

These settings are set up as a way for you to be able to open and move around parts without excessive lag, but they won’t permanently shrink file sizes.

CATIA: Optimized for Complex Product Structures

CATIA doesn’t have a lot of commands to simplify the size of parts like SolidWorks has, but it does have features that run in the background to free up space. Things like cache management and data streaming are designed to shrink file sizes as much as possible while giving you full access to each model and assembly.

This is why so many major companies use CATIA for their large and complicated assemblies. It does a great job of shrinking file size without getting in the way.

Siemens NX: Advanced Techniques for Enterprise-Scale Assemblies

Siemens NX has features that work like a combination of the offerings of CATIA and SolidWorks: there are lightweight options, as well as background data-shrinking processes. NX also connects with PLM environments like Teamcenter to offload a lot of the processing power required to open, store, adjust, and share files. Through Teamcenter, you’ll be able to open larger files much quicker.

Comparing Capabilities: Which CAD System Scales Best?

In our experience, any of the major CAD programs do a good job of scaling up. SolidWorks, NX, CATIA, Creo, Inventor, and Solid Edge are all acceptable options. At a certain part, files can get so large that there’s no CAD program that can keep up without lagging: it boils down to your computing power and ability to simplify models.

We have access to every major CAD program, so you can ask us for first-hand experience or have us handle your CAD projects.

Best Practices for Managing Extra Large Models

One way to handle really large models is to employ some form of PDM or PLM system, like Teamcenter, Windchill, or SolidWorks PDM. These solutions take a lot of the processing tasks away from your local computer so you can open larger files with fewer issues.

Another option is to utilize sub-assemblies. If your assembly has a lot of individual parts that are constrained together without subassemblies, you’ll be asking your PC to do a lot more processing.

Finally, consider simplifying each model. Opting for fewer features in the Feature Tree can shrink every file size, and the size savings will add up. Instead of using four cut commands to make a part, can you get creative with a single sketch and single cut command?

Conclusion

Dealing with massive files can lead to a lot of slowdowns, crashes, errors, and headaches. You can use some of our tips to reduce the size of your files, or you can outsource the work to our pros at CAD/CAM Services. We have incredibly strong computers that can open bigger files and streamline your operation. With access to every major CAD program, you can trust our experts for any of your 2D or 3D CAD needs. Get a free quote today.

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