Design Optimization - Tips and Tricks

As a Mechanical Engineer, I often get asked to design complex and unique models for various applications. Regardless of what is being designed, the overall task remains the same - starting with an initial sketch and turning it into a complex part for the specific function. How we arrive at the resulting design is unique to every engineer. Some start with a complex drawing and other start with a simple drawing and add on the features separately. Most of these items are user preferences but some tasks can hinder the design effort and can cause heartache later in the design process. There also seems to be a hidden feeling by design engineers that the fewer the number of features in a model, the less complex it is. A lot of my peers strive to have the minimal amount of features in a part and ultimately make the part with a few very complex and difficult features. This sounds great in theory, but when time comes to make modifications to the part in the design process, they run into issues and errors. Here are a few tips to try to keep from setting up a trap for yourself in the future as the design of your part progresses.

Keep your initial sketch simple. Most likely this sketch will need to have it's dimensions adjusted or changed if the mating component changes. Having a complex initial drawing might cause some issues for you down the road. Be sure to use your best judgment and keep in mind that this depends heavily on your design. Based on my experience, the more complex your initial drawing is the more likely you'll run into issues if you have some size modifications you need to make down the road.

Perform cuts and extrudes as the second operation. Do not have chamfers, rounds and other small and relatively easy operations inserted between the major operations. This will help to eliminate cascading problems, especially if this cut/extrude depends on a round or chamfer.

Add holes and other small features that you need so that you can make sure your chamfers and rounds designed appropriately.

Add rounds and chamfers as the final features. Try to keep them separated if you can and label them so that if you do run into errors you can easily identify them and delete them if necessary. Knowing your model and design and properly naming the features will help increase your efficiency when designing. Keeping all of your rounds and chamfers all together can be a great way to make a single modification that will change all of them uniformly, but this can also cause you problems as well. The bottom line is to use your judgment and make sure that you use the correct tool for the correct job.

Every design is different and can be optimized in it's own way. It is important to understand that simplification and optimization of a design may result in more features but will help you to rebuild and fix the model in case you are forced to modify the initial design. Good engineering require organization, problem solving and most importantly good judgment to make sure you are using the right tool for the right job.