A Behind The Scenes Look At Our CAD Process

In the ever changing realm of engineering, innovation and problem solving is key to progress. In the past 30 years one of the of the pivotal technologies that has significantly transformed the landscape of engineering is Computer-Aided Design (CAD). This technology has revolutionised the way engineers conceptualise, design and analyse their projects. In this blog, we will delve into the intricacies of CAD Design, understanding its importance, fundamental aspects and indispensable role it plays in engineering projects. 

The Importance of CAD Design in Engineering

in the contemporary world, where precision and efficiency are paramount, CAD Design stands tall as a cornerstone of modern engineering. CAD, or Computer Aided Design, refers to the use of computer software to create detailed 2D technical drawings and 3D models of physical objects. The models serve as a visual guide for engineers, architects and designers throughout the product development process. Gone are the days of solely relying on paper sketches and manual drafting to communicate ideas; CAD has ushered in a new era of accuracy, speed and design flexibility. At Twenty20 Engineering all of our projects use some form of CAD at some stage of the project, it is a fundamental aspect to deliver a high quality project or product to our clients.

Why Understanding CAD Design Matters

Understanding CAD design is not just a matter of technological prowess; it is a fundamental necessity for anyone involved in the field of engineering. All of Twenty20 Engineers are formally trained to use multiple types of CAD software, ensuring we have a broad range of skills to deliver a project.

With the digitalisation of the design processes, engineers need to be well versed in CAD tools to remain competitive and efficient. Additionally proficiency in CAD fosters seamless communication between teams members, clients and stakeholders. CAD bridges the gap between abstract sketches and ideas and tangible prototypes, enhancing the overall efficiency of an engineering project.

The Fundamentals of CAD Design

What is CAD (Computer-Aided Design)?

At its core, CAD is a technology that uses computer hardware and software to aid in the creation, modification, analysis or optimisation of a design or engineering project. CAD enhances the productivity of the designer, improves the quality of the design, creates a database for manufacturing and can even assist with simulations and analyses. CAD software applications vary widely and used in various industries including:

  • Automotive
  • Aerospace
  • Architecture and Construction
  • Electronics
  • Mechanical Design Applications

The Evolution of CAD: From Paper to Pixels

Before the development of CAD into the sophisticated tool that it is today, design engineers and architects relied heavily on manual drafting techniques. As we discussed in our previous blog From Sketch to Perfection: How CAD and Design Refines Your Concepts, manual sketches and drafting techniques are still useful tools in a designers toolbox for the idealisation and conceptualisation phases of a project. Many projects start life as a basic sketch on a piece of paper. 

Once a concept has been agreed upon CAD can be used to accelerate the project to an accurate 3D model which can be used as a virtual prototype. By reducing the reliance on the sketching and manual drafting and replacing it with CAD this has reduced the amount of labour, time and errors made in the design process. The evolution of CAD has dramatically streamlined the design process, the introduction of computer based drafting tools has allowed engineers to create intricate and complex products with a few clicks of a mouse. The time and effort reduction is reflected in the reduced time to market for all products, most notably Fast-Moving Consumer Products (FMCP) such as the Apple iPhone.   

The Role of CAD Design in Engineering

Integrating CAD into the Engineering Workflow

CAD seamlessly integrates into the engineering workflow for all projects and is an integral part of the design process. From the initial concept to the final product, CAD plays a pivotal role at each stage. Once the CAD model and 2D technical drawings have been developed for a project other manufacturing data can be produced, such as a Bill of Materials (BOM), Part schedules, assembly and buildability instructions. Other outputs could include specific file types for 3D printing, laser cutting and sheet metal bending.

Benefits of CAD Design in Engineering Projects

The benefits of CAD Design in engineering projects are multi-pronged. Firstly, CAD enhances productivity by expediting the design process. What once took several weeks to sketch and draft manually can now be accomplished in a matter of days or even hours with CAD software, depending on the nature of the product. Secondly CAD facilitates precision and accuracy. Engineers can accurately design to exacting measurements, ensuring components fit together perfectly. This level of accuracy minimises errors, clashes and tolerance problems, reducing costly design revisions and rework. 

Moreover, CAD design enhances collaboration and communication between the design team and external stakeholders. The design files can be easily shared and modified in multiple formats, allowing stakeholder input and feedback. This collaborative environment fostered by Twenty20 Engineering leads to creativity and innovation, facilitating the creation of cutting edge products.

The CAD Design Process Unveiled

Step 1: Defining the Project Scope and Requirements

The CAD design process kicks off with defining the project scope and specification. This phase involves gathering client and stakeholder input. Engineers need to understand the objectives of the project, functional requirements , budget constraints and intended deadline. By establishing clear design constraints and parameters, engineers can set the foundation for the rest of the design journey. 

Step 2: Conceptual Design

Once the project scope has been defined, engineers move on to the conceptualisation phase as discussed in our other blog Sketch to Perfection: How CAD and Design Refines Your Concepts. A key part of this is manual sketching and drafting as well as brainstorming and ideation workshops. Engineers explore various possibilities, with different thoughts providing various different design solutions to achieve the project objectives. Which are then narrowed down to a final concept

Step 3: 3D Modelling

With the conceptual design and sketches in place the next step involves 3D CAD modelling. This is to take the idea from a piece of paper to a virtual prototype transforming the 2D sketch into a detailed 3D model. Using CAD software the engineers create 3 dimensional representations of the product or structure. This part of the project requires a deep understanding of engineering, geometry and spatial relationships. Engineers meticulously design every component, ensuring precision and accuracy. 3D modelling avoids design errors such as clashes and tolerance issues, allowing the necessary adjustments to be made before moving forward.

Step 4: Analysis and Simulation

Once the 3D model has been created, engineers can construct thorough simulations to test and analyse the performance and feasibility of a part or assembly. Advanced CAD software allows for such simulations as stress analysis, fluid dynamics, thermal analysis and cyclic/dynamic loading. Engineers can then evaluate the data provided and identify potential weakness or areas that require improvement. 

Step 5: Iteration and Refinement

The CAD and design process is iterative by nature, based on the evaluation of the simulation data, engineers can refine the design. They make the necessary iterations revising the model to mitigate against any shortcomings within the design. Continuous improvement is a key phrase. Engineers of all types collaborate closely, discussing potential solutions and enhancements. This will continue until the design reaches an optimal state, ready for the 2D technical drawings and manufacturing data to be created. 

Step 6: 2D Drafting & Manufacturing Data

Once the design has been analysed and the 3D models checked and approved, the engineers will create detailed 2D technical drawings, manufacturing data and schedules for production. Key dimensions, tolerances and annotations will be shown on the technical drawings to effectively communicate the design intent to the manufacturing and production teams. Detailed clearly set out 2D technical drawings, schedules & BOM’s and assembly instructions will provide the basis for the successful manufacturing of the product.


In conclusion, CAD design stands as a testament to human ingenuity and technological advancement. The tool has transcended the boundaries of traditional design methodologies, ushering in an era of unparalleled precision and accuracy in engineering, vastly improving the quality of all products. From its humble beginnings software advancement has enabled sophisticated design solutions to be developed and accurately manufactured. 

This blog has explored the importance of CAD to engineering, emphasising its pivotal role in modern engineering. Understanding CAD software is not merely a skill, is necessary for engineers to develop the innovative designs of tomorrow for their field. By becoming a seamless part of the engineering workflow CAD has revolutionised the way projects are conceptualised, designed and analysed. 

For Twenty20 Engineering’s team no two projects are the same, each has unique requirements. Using CAD as part of the engineering workflow with highly skilled engineers ensures that each project is accurately and precisely detailed. Ensuring a smoother route to fabrication and assembly, and a faster route to market for our customers.   

More Posts

Contact Us