The SolidWorks Geek

You don’t need a CAD Manager to do the right thing.

Miss Me? Things have been quite here lately and I have a very good reason for it. A little over a month ago I started a new job as the CAD Manager for a growing Solar Power company in Southern California. I was brought into this company for my CAD management experience and my first task was to create a working design control system for the company’s engineers and designers. Coming into a company without a CAD manager can sometimes be a scary feeling. Not only was I not familiar with the technology and products developed in the company but I have to spend my first few weeks trying to get a handle on the CAD systems. This is not a task for the faint of heart and it often requires many late nights and large bottles of Excedrin.

This past few months have reminded me of what happens in a company when there is no one person to guide the engineers, designers, drafters and other SolidWorks users on good documentation and modeling practices. In this tough economy many small companies cannot hire a CAD manager to come in and create a system. This is often left up to the most experienced designer or engineer. Unfortunately, even if you are among the elite when it comes to creating complex models and assembly, you will not necessarily be ready for the task of creating a viable design control system. There are many things to consider when creating a new system or when trying to streamline an existing document control system. I have decided to share with you a few things that I have come up with over the past few years. This is not a complete list but these are the most common problems I encounter when entering a new company.

Just a disclaimer. My solutions or ideas may not be what some other “industry experts” believe and I know that. Everything that I will cover here is based on my own personal experience and things may work differently for you. Also, I have spent the past 10 years working in medical with FDA requirements and tight controls may not be what you organization needs. The only way to know for sure to sit with your users, managers and other departments to design a system that works best for your organization.

With that being said, here are the first five of my 20 tips to organizations that do not have a CAD Manager:

Use a PDM system

PDM (Project Data Management) systems are extremely useful to tracing design changes and controlling released documents. SolidWorks does offer two levels of PDM. SolidWorks Workgroup PDM is a nice little application that is available for free when you have a SolidWorks Professional or above. Workgroup PDM is designed for smaller groups of no more than 15 or so, although I have had Workgroup PDM work with 150 concurrent users with over 200K documents. For larger organizations, you will want to go with Enterprise PDM. Enterprise PDM was designed for controlling every document in a larger organization and even allows for multiple work flows.

If your organization has more than a handful of drawings, you will benefit greatly from the implementation of a PDM system. For a small investment of time, you can have a system that will help eliminate costly design design errors cause by improper revision control, part referencing, design controls and group management.

Store all SolidWorks Models and Drawings in one location preferable on a shared network drive if PDM system is not used.

Even if you chose not to use a PDM system to control your drawings, use a good product structure tracking system. Build a folder structure in a shared location that replicates the design tree. Using a tree of folders rather than grouping documents by type or part numbers will make it easier to tract the product relation and will help when making changes to existing designs or creating new products.

Instead of making changes directly to the models in the shared locations, copy the file locally to make design changes. This will ensure that released documents are not prematurely updated without going through the document control process. When changes to models and drawings have been approved, move them to the shared location and update any references that should point to released data. Good design control will save you hours of extra work in the long run when trying to adhere to a good document control system.

Work closely with Document Control to ensure that proper file naming and revision control standards are followed.

I have noticed that for some reason Document Control is considered incompatible with design engineering. In my professional career, I have had to work close with a variety of document control departments and I have learned that they are only concerned with making a system that works not impeding the creative process required for product development. Maintaining an open communication between engineering and document control will only help to decrease the time it takes for drawing changes to be correctly released in document control.

Although some Document Control manager can sometimes be a bit scary, even the hardest can be softened with fresh donuts and a really good cup of joe. Have a chat and learn not only how documents progress through the system but also gain an understanding as to why certain things are important. A certain rule may seen useless and stupid to follow but once you see how it can affect other areas of your organization, you may be may find it easier to take a couple of extra minutes to do the right thing.

Fully define design intent

Not every issue that may come up at work is caused by bad file references, or poor revision management. Sometimes design issues may not be as obvious as a referenced part not being found or revision mismatches in drawings. Sometimes a design just doesn’t work like it was supposed to and it can be extremely difficult to track down the trouble area. It would be a lot easier to troubleshoot a design flaw when you can be confident that the design intent is properly defined in the creation of the manufacturing documentation.

You can ask a hundred engineers and designers what is design intent and you will more than likely get at least a hundred different answers. In my opinion, design intent refers to how a part, assembly and drawing is modeled, defined and dimensioned and how dimensional changes to geometry can affect how the whole thing works. For example, you can specify a hole location on a plate and how it interrelates to another part or assembly. If during the design process the diameter of a hole is changed, how are other areas of the part affected? Does the center point of the hole need to be moved to maintain a specific distance from another feature? Does the diameter need to be matched on a different feature? Does the change affect additional dimensions on the drawing that need to be noted?

Here are some steps that I use to control and specify design intent:

1. Fully define sketches
2. As much as possible, dimension part sketches as you would on the actual drawings.
3. If the distance to the edge of a hole is more important than the center of the hole, dimension it that way. As the diameter grows, the distance will always be maintained.
4. Mate assemblies in such a way that the way the parts are assembled when manufactured is closely replicated. This will allow you to identify design issues as the design progresses.
5. If possible, import annotations from parts into drawings. It may seen like extra work but it will help you to ensure that the design intent is understood when creating sketches.
6. Consider how relationships between features are affected when the size, form or location is defined by a dimension and a tolerance zone.

Do not overwrite drawing dimensions.

This really should go without saying but you may be surprised how often I see the extremely poor practice in many companies. Luckily it is not something that has been able to be fixed with a slap upside the head. But seriously, Some may think that the 5 minutes they saved by overwriting dimensions on the drawing rather than making the model changed saved a couple of bucks but it can be extremely costly in the long run. Unfortunately, the person making the change is rarely affected by his own ignorance, instead the issue may not manifest itself until weeks, months or even years later when parts being manufactured do not match the parts being designed. This can be a costly mistake that could have been avoided if the extra five minutes were used doing the right thing when incorporating a change. If your boss is breathing down your next to expedite a drawing, calmly describe the reason why a couple minutes is needed to make the design change. He will thank you in the long run…hopefully.