Mechanical Design First Stage: Studying Engineering Graphics.
According to university plans, you should first study mathematics. However, if you’re working in the mechanical industry, you have a significant advantage because you can combine practice with theoretical learning. Begin with a sensory understanding, then elevate it to rational comprehension, and finally return to production practice. This cycle repeats indefinitely. Studying Engineering Graphics will help you understand technical drawings, and you can leverage your work opportunities to accumulate practical experience quickly.
Engineering Graphics consists of two parts: Descriptive Geometry and Mechanical Drafting. Descriptive Geometry teaches you the basic principles of perspective. The most important aspect of technical drawings is rigor, which is different from ordinary drawing. There are strict perspective requirements, and if the perspective is wrong, the drawing will be wrong. This would make it impossible to apply in production or communicate with other designers.
Mechanical Drafting, on the other hand, deals with specific expressions. If Descriptive Geometry is the internal mastery, then Mechanical Drafting is the application. It covers how to represent different components, the differences between part drawings and assembly drawings, how to draw sectional views, etc. The so-called drawing software simply shifts these contents from hand-drawing to computer-aided drawing. Personally, I believe there is no essential difference. Engineering Graphics is fundamental in engineering. It allows you to understand others’ drawings and transform your own designs into drawings that others can comprehend. Once you learn this course, you can start accumulating practical experience.
Recommended books: I personally think that the textbooks used in major universities’ science and engineering programs are sufficient. You can casually pick up a textbook from Tsinghua, Shanghai Jiao Tong University, or Harbin Institute of Technology for self-study. You don’t need a deep mathematical foundation, but spatial imagination is essential.
Mechanical Design Second Stage: Studying Principles of Machinery and Mechanical Design.
In fact, I’ve been hesitating about what to study in the second stage. If you start with mathematics, you might not immediately see the connection between math and mechanical design (once again, let me emphasize that math is truly important…). If you start with Principles of Machinery and Mechanical Design, there will be a lot of math-related content that may be hard to understand. From the perspective of practical production, which differs from a school approach, I boldly recommend that you begin with Principles of Machinery and Mechanical Design, even though it might take longer and involve some detours. But don’t rush to drive yourself crazy.
Principles of Machinery introduces the structures and motion principles of common machines, excluding material factors. On the other hand, Mechanical Design takes material factors into account and teaches you how to transform designs into actual products (any product necessarily relies on some kind of material for support; no product can be made without material). Both courses involve a significant amount of mechanics analysis and mathematical calculations. In fact, beyond creativity, mathematical calculations form the foundation of mechanical design. To bring any product to life, extensive calculations are required, and every part must go through calculations to ensure it meets mechanical requirements; otherwise, the product will be unsafe. No one wants to see a product break down or even injure someone during use, and many accidents occur due to insufficient structural strength caused by improper load-bearing designs.
I’d like to express a point again: mechanical design is not as simple as you might think—it’s not just learning mechanical drawing or a drawing software. If you think it’s simple, it only means you don’t yet fully understand mechanical design. From something as small as why a bolt is M10 rather than M8, or why bolts are positioned at the corners instead of the middle of the sides, all of these require a lot of mechanical analysis, mathematical calculations, and practical experience. It’s definitely not as simple as “I’ll save costs by replacing five bolts with four or switching from M10 bolts to M8 bolts.” If you really do this, it might seem fine at first, but it could also lead to disastrous outcomes—machinery breakdowns, personal injuries, or even fatalities—situations we can never afford to face.
Mechanical Design Third Stage: Advanced Mathematics, Linear Algebra, and Probability and Mathematical Statistics.
If you’ve made it through the previous stages, this is where you’ll face the true internal mastery required to become a mechanical design engineer. For Advanced Mathematics, I recommend the version by Tongji University, and for Probability Theory, use the one from Zhejiang University. At first glance, these subjects seem completely unrelated to mechanical design, and they’re abstract and highly difficult. However, without mastering them, you will never become a mechanical design engineer.
Throughout my life, I’ve seen many students who performed excellently in their early years but eventually failed to get into prestigious high schools or universities due to poor math skills. Mathematics is fundamental—if you can’t master it, you might as well give up the idea of becoming a mechanical design engineer. As harsh as it sounds, this is the reality. How many people are willing to admit that they’re not as good as others?
But people are not the same. If something isn’t right for you, it just isn’t. If you’re not cut out for it, you’re not cut out for it. We can’t let Guo Jingming play in the NBA. No matter how hard Xiaosi tries, he can’t make up for the gap between him and NBA players. Those who say “hard work leads to success” are offering misguided comfort. In the pursuit of the same goal, many people are eliminated because they lack the talent, regardless of how much effort they put in.
Mechanical Design Fourth Stage: Theoretical Mechanics and Strength of Materials.
If you’ve made it through the math courses, congratulations! You’ve conquered the hardest part. But don’t be fooled—there are still plenty of challenges ahead. Theoretical Mechanics introduces force analysis and motion analysis, while Strength of Materials involves mechanics analysis when considering the microscopic deformation of materials.
Both Theoretical Mechanics and Strength of Materials are the foundations for Principles of Machinery and Mechanical Design. Math, in turn, is the foundation for understanding these two subjects. Many force analysis and calculations in Mechanical Principles and Mechanical Design can be traced back to the principles in Theoretical Mechanics and Strength of Materials. Personally, I believe that the process of mechanical design is essentially a process of force analysis.
After completing these two courses, I recommend revisiting Principles of Machinery and Mechanical Design once more, especially those parts you didn’t fully understand the first time. Now that you’ve learned so many foundational courses, you may finally understand things you struggled with before. Take the time to fill in the gaps—it will greatly benefit your knowledge!
Mechanical Learning Fifth Stage: Interchangeability and Measurement Technology, Metalworking Technology, Electrical Engineering, etc.
If you’ve made it this far, you should be at around the level of a second-year mechanical engineering student. By now, you’ve mastered around 70-80% of the core knowledge required, and you’re starting to see the light at the end of the tunnel as a potential mechanical design engineer. However, you still lack many skills, and that’s what the next step involves. This stage will cover many courses, and I can’t list them all individually. Their importance is generally similar—if you can’t use them, there’s no need to learn each one, but learning them is always beneficial. You can choose and prioritize based on your industry, as this phase is more application-oriented.
If you’ve made it through all the stages above, congratulations, you’ve finally entered the mechanical design field—you’ve just gotten your foot in the door. By now, you should realize that the mechanical industry isn’t as simple as just drawing diagrams. Every structure, every screw, needs to be backed by reasoning and analysis. If you’re learning entirely on your own while working, I estimate that mastering the above stages thoroughly will take at least two to three years, but it could take four to five years or even a lifetime.
Once you’ve entered the field, you can rely on your self-learning ability to continue learning, growing, and progressing in your actual work.
To end with a piece of advice: “Strict standards, expert skills.”