Swapping Models in SolidWorks

Design Automation is very powerful when creating unique “same as, but” models for new jobs. But in many cases, people are doing configure-to-order (CTO) just as much as they are doing engineer-to-order (ETO). Configure-to-order means utilizing standard components and using the automation to determine the logic for which component, or which size of a component, to put in an assembly. Configuring an automated design sounds simpler, and in many ways it is, but there are a few things to note and some design automation best practices to follow when planning to swap models in SolidWorks. And these tips apply whether you’re using DriveWorks, TactonWorks, or virtually any other design automation tool for SolidWorks.

Mechanical Design Automation tools for SolidWorks utilize the standard Replace Component functionality to allow users to swap out a component in the master model for the component of their choice. But the tricky bit with Replace Component is getting SolidWorks to reconstruct the mates on the newly inserted part. We are frequently posed with the question, ”how can we make sure that the mates resolve properly?”

The key is consistency. All mates, or assembly constraints, have references within the components that are being mated. Whether those are planes, faces, axes, or some other form of hard or reference geometry, SolidWorks records a pointer to them in the definition of the mate. If SolidWorks sees the same reference in the new part, the mate will resolve every time. So the answer is simple. If a user mates to a plane named “Mate Plane” in the master component, and they have a plane named “Mate Plane” in the replacement, the mates will resolve, right?

Not so fast!! This is the most common faulty assumption. The name of the reference is a “pretty” name for users. As far as SolidWorks is concerned, that name only exists in the user interface. SolidWorks has its own internal identifier for the geometry reference. If there are two planes in different models that were created differently, at different times, they are almost certain not to have the same internal identifier, regardless of they are named. And they will not resolve when replaced.

So the design automation best practice is to always use the same references in every model. Front/Top/Right are always good bets as they are in every model and they always have the same internal identifier. What if models don’t have the Front/Top/Right planes in the same place for each of the models to be swapped? Well, change them. Yes, it could potentially be a lot of work. But consider it a tax for not being able to anticipate the unique CAD modeling needs of design automation.

So if you’re designing models now, take the replacement requirements into account. Design everything around your default planes. If that is not possible, for example if you need to mate to an axis, create the reference geometry first. Create a starter part with the reference geometry that you need, then do a File -> Save As to create all of the derivative models. We have yet to meet a component that we could not model with these methods. And the result is 100% bulletproof component replacements. Think your CAD models can’t be made swappable? Drop us a line. We love a challenge.

Tags: assembly constraints, CAD, CAD model, configure-to-order, Design Automation, design automation best practice, DriveWorks, engineer-to-order, Mechnical Design Automation, reference geometry, SolidWorks, TactonWorks