The 10 Commandments of Mechanical Design

Whether you’re a seasoned engineer or a wet-behind-the-ears novice, there are some immutable laws that must be followed to produce a good mechanical design. If you don’t follow them, you’ll be sentenced to eternal hellfire and damnation. Either that, or you’ll find yourself having to do lots of redesigning and pulling out of hair.

So, get your tablets of stone at the ready, lift your eyes to the heavens and get ready for some sage advice from the engineering gods.

1. Thou shalt start simple

Ever heard of the acronym KISS? It stands for Keep It Simple, Stupid. Not bad advice for the early stages of a mechanical design. In fact, just grab yourself a pencil, ruler and some scrap paper and start making rough sketches. This is your chance to get all your ideas out there, in 2D projection format or isometric, it doesn’t matter. This is just a basic starting point for your design, so let loose!

2. Thou shalt not value form over function (not to begin with anyway)

The key thing for a good mechanical design is… wait for it… to make sure the darn thing actually works. Yes, it sounds obvious, but if you start thinking about aesthetics in the early stages, it’s all too easy to come up with a design that has little chance of working practically.

3. Know your CAD

After getting some hand-drawn ideas down, it’s time to boot up the computer and get digital. Whether you’re using SolidWorks or AutoCAD, you need to be able to use the software at an intermediate level at the very least. If your knowledge isn’t up to scratch, it’s probably worth investing in a course. There are plenty of relatively cheap e-learning courses on sites like Udemy that will quickly get you up to speed if you’re a bit rusty.

4. Be aware of relationships between parts

As you design the piece, make sure that you’re paying close attention to the possible interactions or relationships between the parts. For instance, make sure that screw assemblies aren’t going to interfere with moving parts. Getting these right early on in the design will save you massive headaches later on as you try to re-engineer things.

5. Think green

Designing environmentally-friendly mechanical parts is so important in this day and age. Be responsible with material choice, efficiency and durability. All of these things will increase the sustainability of your design.

6. Make it aesthetically pleasing

Ok, so earlier we said ignore form for function. But there comes a stage in the design when you can divert your attention to the prettiness of the design. There’s no reason why mechanical designs can’t be attractive. Just think like the engineers of the Victorian era who created mechanical systems that were beautiful, as well as functional. It’s quite an achievement to transform hulking great chunks of metal into a graceful, flowing system of moving parts.

7. Log your thoughts

Write down every major consideration and justify each change you make. There will come a point where you’ll have to present your design to one or more people and having a logical account of your design choices and revisions will help to justify elements of the design.

8. Present your design correctly

Make sure you use all of the correct design standards and presentation requirements. It may not seem like a big deal to have your dimensions displayed incorrectly, but it makes you appear less professional to anyone who sees it. If the design brief asks for specific presentation features, then make sure to include them.

9. Don’t be afraid to innovate

Although we are initially looking to keep things simple, as the design progresses you can add more complex features or innovative touches. The technical revolution has meant that there is a rapid pace of change, and new ideas are being introduced continually. Stay abreast of changes in your industry and be inspired to come up with innovative design solutions where possible.

10. Check, check and check some more

Checking your design can seem like the most boring and laborious part of the process. If that’s how you feel, you really need to change your outlook, as it’s probably the most important part of it. Get into the habit of checking as you go, use common sense, repeat your calculations and check for dimensional accuracy. When you’ve got to an appropriate point with the design, go away and do something else for at least a couple of hours, then return with fresh eyes to check the design. This will help you to be more objective and accurate with your checks. Also, make sure that someone else checks your work. Don’t be tempted to skip over this part.