The Importance of Revisions for CAD Data

Changes are inevitable, but how do you keep track of the history of these changes? For many things, proper revisioning practices can make your projects run much more smoothly.  By not implementing a revision system in your processes, you’re opening yourself up to pain points such as quality issues, miscommunications, and more. With a multitude of solutions available, there’s no excuse to not get started today.

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 Topics covered in this post:

1. What is a Revision?

2. How are Revisions Communicated?

3. The Importance of Revisions

   1. Avoiding Miscommunications

   2. Avoiding Time Loss

   3. Providing a Fallback

4. How to Manage Revisions for your Engineering Data

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What is a Revision?

When you make a change to something, you are revising it and the changes you make are the revisions. Therefore, a revision for CAD data is a changed version of a product. This can be further broken down into major and minor revisions. Major revisions are generally reserved for larger changes like actual modification to geometry, while smaller changes such as documentation updates or fixing the spelling on a drawing would generally be classified as a minor revision. Many organizations use major revisions alone. The two main types of schemes are alphabetical or numerical. Minor revisions are generally numerical. This leads to the following possible revision schemes.

• Major Revision Scheme

  • Alphabetical: A, B, C, …

  • Numerical: 1, 2, 3, …

• Major and Minor Revision Schemes

  • Alphabetical: A.1, A.2, B.1, …

  • Numerical: 1.1, 1.2, 2.1, …

 Some organizations will implement a dash “­­ - “ as the initial revision prior to initial release. This aligns with the ASME Y14.35 standards for tracking changes with engineering drawings. Also stated in these standards, all letters in the alphabet can be used for revisions, except I, O, Q, S, X, and Z, as these can be mistaken for numbers. The letters are to be used in an uppercase format. Upon reaching the end of the alphabet, an additional letter is added. For example, if following the ASME Y.14.35 standards, AA comes after Y, BA comes after AY, so on and so forth, and does not exceed YY.

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How are Revisions Communicated?

Sure, revisions are great for signifying a change has been made, but how can you communicate that change? At a bare minimum, including the revision letter/number in the title block of your engineering drawing or metadata/properties of your 3D model will at least let a viewer know there has been a change. They can then compare the revision they had prior and look for any differences. When it comes to engineering drawings, a couple additional options that can be implemented are revision clouds, revision tables, and revision symbols.

Revision clouds draw a shape with rounded bumped edges around an area that has changed to quickly draw attention. Revision tables often keep a history of revisions, a basic description of the change, the date, and who approved the change. Revision symbols, generally used in conjunction with revision tables, place a marker with the revision encompassed by a shape, often a triangle. These markers can be placed near the change or attached with leaders. To best communicate your changes, a combination of these tools can be used.

Revision Cloud

Revision Symbol

Revision Table

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The Importance of Revisions

Making sure your products are up to date is an important factor in success, however, without implementing a revision process, you’re potentially missing out on several benefits. You’re busy, so busy that you don’t even want to think about trying to implement a new process. Luckily, taking the time to learn how to properly revision your data is a onetime cost whereas the benefits are forever.

Avoiding Miscommunications

Whether it be internal or external, having your revisions properly documented can greatly cut down on miscommunication. For example, consider the case of sending out product drawings to a manufacturer. They now have at least two versions of this drawing. If someone was not informed there was a change, they may continue to produce the original version. This can be costly and set your project timelines back.

Avoiding Time Loss

Aside from losing time due to miscommunications, proper documentation of your revisions can help prevent time loss in the development process. One example of this is having someone working on a past revision without knowing. According to a study carried out by Tech-Clarity, approximately 20% of an engineer’s time is spent on out-of-date information! Not only was their time wasted, but depending on your system, you may not be able to get back to the correct state. Past revisions can also be studied to observe what has already been tried and prevent unnecessary duplicate work.

Providing a Fallback

Ideally, you’d never need this functionality, but worst-case scenario, by having a proper revision system in place, you’ll always have your past revisions to fall back to. If a change is made that ends up not working out, you can analyze the previous revision to see exactly how to revert it back to its previous state.

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How to Manage Revisions for your Engineering Data

At the very least, you can implement a revision system of sorts by saving different revisions of your files with a suffix of the current revision letter/number (i.e. SWYFT-15848_REV A). This provides you with the ability to fall back to previous versions and keeps that history intact. As for communicating the updates, the availability of the tools discussed depends on the solution you are using. The examples shown in this blog were taken from SOLIDWORKS. Otherwise, manual notes can be added to your engineering drawings with most software. While that’s a good place to get started, there are many better solutions.

To truly take advantage of the revision process, you’ll likely want to implement some sort of data and lifecycle management solution. This will store all your past revisions and often lock previous revisions, preventing users from editing anything by mistake. With some options, you can even add your external partners with controlled access, always giving them direct access to the latest revision. This can greatly cut down on miscommunications and project setbacks.

There are both on premise and cloud solutions for data and lifecycle management. There are advantages to both, however, when it comes to someone that is just getting started, the cloud solutions really start to shine. With the ability to get up and running without the need for expensive hardware and lengthy implementation times, cloud data and lifecycle management is a great solution that provides many additional benefits that quickly justify the cost.

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Conclusion

You wouldn’t walk past money on the ground, so why pass up the opportunity for savings with a proper revision system. 3DEXPERIENCE provides you with cloud data and lifecycle management tools that work seamlessly with your CAD software and can get you up and running in no time! With cloud storage, lifecycle management, issue management, and more, you’ll be able to start implementing industry best practices and take your organization to the next level while staying flexible. Plus, being a cloud solution, it’s easier than ever to get started. Without the need to purchase the costly server hardware and pay for maintenance, data management isn’t just for large organizations anymore.

Interested in further evaluating how the benefits of revision and data management with 3DEXPERIENCE can benefit your organization? Contact us today to start the conversation.