What is CAD?
Computer-Aided Design (CAD) is a technology which uses computer software to develop, modify, analyse, and optimise various products, structures, and their systems. CAD is currently being used at Twenty20 Engineering to streamline the design process and improve its accuracy and efficiency when creating 3D or 2D models for clients.
CAD allows the designers at Twenty20 Engineering to create detailed 3D models and Isometric representations of products based on our client’s requirements. The software used at Twenty20 Engineering provides a wide range of tools and features to manipulate, visualise, and showcase engineering designs to clients. Twenty20 Engineering are experienced uses of:
- AutoCAD
- SolidWorks
- Tekla Structures
When the concept has been finalised the designers at Twenty20 Engineering start to create precise geometrical shapes, lines, and curves to develop the foundations of the product being designed. As the foundation has been set designers make use of modelling options to create solid models by extruding, revolving sweeping or lofting 2D shapes, to create components and parts.
The assembly stage is used to join multiple components together to create complex sub-assemblies and assemblies. With all connections modelled accurately to build a realistic 3D version of the final product in a virtual space.
Rendering and visualisation features are used to provide our clients with a realistic visualisation of their final products or machines before manufacturing commences. Our detailed presentations at this stage have helped a lot of our clients to spot final adjustments or make further improvements to their products before their products arrive at the end user or onsite.
The Importance of Concept Refinement
Concept refinement is a critical process at Twenty20 Engineering, this can be an iterative and continuous process, to enhance accuracy and performance of a design. Refining the concept narrows the design window to ensure the final design meets the critical objectives of our customers specification. Here are a few key reasons why concept refinement is crucial:
- Increased precision: Product design often starts with vague or general ideas. Refinement allows designers to break down abstract concepts into a detailed well-defined design which improves communication and understanding among the team and the clients.
- Optimised solutions: At the design development stage, concept refinement allows for the evaluation of various possibilities. Which allows the design engineers to select and develop the most effective and efficient solutions.
- Risk Reduction: By concentrating on potential limitations and weaknesses of the concept, refinement reduces the risk of failure or unexpected issues in the design process.
- Innovation and creativity: Refining a concept encourages creative thinking and the discovery of alternative ideas. This stage provides a platform for new or better ideas and solutions to be implemented.

The Art of Sketching
Exploring Ideas on Paper
Exploring ideas on paper is a powerful and liberating process which allows the draftsman to unleash the imagination, develop new concepts, and innovative solutions. Here are some key points why exploring ideas on paper can be beneficial:
- Provides Discussion Points
- Visual Communication
- Visualisation
- Rapid Iteration
- Problem solving
- A picture paints a thousand words
During product design development at Twenty20 Engineering, sketching is used to create quick drawings to visualise concepts before starting a more detailed and time-intensive process of using CAD design to create 2D and 3D models. Sketches help to convey a visual or physical representation of concepts more effectively than words. It is a communication tool used between our draftsman and clients to facilitate discussion of ideas and objectives.
Putting ideas on a paper helps to visualise and convey conceptual thoughts. It transforms vague concepts into solid representations, making them easier to analyse and further develop the solutions that meet the design criteria. Concepts developed on a paper are flexible and allow quick iterations. It can be drawn, modified, refined, or erased, encouraging a fast and iterative process. Developing and exploring ideas on a paper can lead to breakthroughs and spot unseen issues which could have led to a failure or unsuitable design.
Twenty20 will usually carry out sketches as part of design consultation meeting with clients to help conceptualise the design and facilitate discussion with clients. This allows us to work collaboratively with customers.
The Power of Visualising Concepts
The power of visualising concepts allows the draftsman to make abstract or complex ideas more tangible, and understandable for the clients. This is a critical part of the journey as the clients see the first looks of their products. Our engineers ensure to go through each detail regularly with our valued clients to assure they will receive the highest quality product. Here are some key reasons why visualising a concept is an effective tool:
- Clarity and understating: When the designers are approached with ideas or customer requirements, it can often be confusing to convey the exact product required in words. Hence visuals can simplify complex information and present them in clear and concise ways.
- Communication and Persuasion: Concept visualisation Is a universal language which is used across different industries specifically engineering, as it transcends linguistic barriers. Visualizing concepts helps communicate ideas more effectively and persuasively.
- Problem-solving: Visualizing the concepts developed can help with problem solving by enabling our design engineers to analyse and identify clashes between components, and other future problems which could arise and propose potential solutions.
- Facilitating Collaboration: Visuals serve as a reference point for our teams and clients to work effectively and efficiently together on a project.
The Evolution of CAD Design
Advancements in CAD Technology
Cloud-based CAD allows for easier understanding of the design process and allows our design team to collaborate more effectively and present real-time updates across multiple devices and locations. This allows closer collaboration with clients as visualised concepts through to finalised designs can be viewed and discussed in 3D once they have been created by our engineers. As cloud CAD computing can be accessed and used directly through web browsers, this reduces the need for our customers to have specialised software applications and high-end computing equipment. Making the design process easier to access, and facilitating deeper design discussions with our clients to ensure we meet their specifications.
Generative design algorithms are computational techniques that us mathematical models, optimisation methods and in some cases Artificial Intelligence (AI) to create and refine design solutions. This helps design engineers to explore a vast range of possible design variations, usually driven by specific design goals and constraints, to generate innovative solutions which might not be easily determined by a human alone. These tools have begun to be integrated into CAD tools, which allows designers to achieve desired design goals and constraints more efficiently. CAD software is continuously upgraded to optimise design efficiencies and latest best practise allowing better development of complex assemblies and components for end users.
When developing a product at Twenty20 Engineering it is crucial to complete, performance analysis such as FEA. This will provide valuable data of how the product will operate once manufactured. CAD software have integrated powerful simulation and analysis tools such as stress analysis, fluid dynamics simulations and thermal analysis. This provides the opportunity for the design engineers and our clients to optimise specific aspects of the design to ensure a closer alignment with the design specification and allow for cost saving decisions where appropriate.
Embracing Digital Design Solutions
Embracing Digital Design Solutions offers numerous benefits and advantages to the designing team, here are 2 key reasons to embrace digital design solutions:
Efficiency and Productivity: Digital design tools streamline and automate repetitive tasks, which increases efficiency and productivity. Designers can create macros within the design software to enable more efficient draughting and modelling. 3D CAD modelling reduces the need for physical prototypes and materials during the conceptualisation phase. It is however desirable to have working prototype of the final design concept. Creating a 3D CAD model reduces the number of prototypes required which saves a lot of time and expense for our clients. As they can view the product virtually and analyse its data and make decisions accordingly.
Realistic Visualisation: Digital design offers advanced rendering and visualization options, allowing designers to present a photorealistic or motion study view of the product. This enhances communication between clients and stakeholders, allowing them to see the design in its environment. This can be taken one step further with the aid of Virtual Reality (VR) headsets, to enable walkthrough and fly throughs of complex designs. In the future this could be used for training purposes to enable the prebuilding and assembly of complex designs, to ensure smooth assemblage of products.

Transitioning from Sketch to CAD
Introducing CAD Software
CAD software is a category of computer software used by design engineers, to develop, modify, analyse, and view products in 2D and 3D models and drawings. The primary purpose of CAD software is to replace manual drafting which was time consuming and not as accurate. CAD software offers a wide range of options based on design requirements. Here are some key features and benefits of CAD software:
- 2D and 3D Modelling: CAD software allows designers to create precise 2D drawings and detailed 3D models of mechanical or electrical products.
- Parametric Modelling: CAD software such as SolidWorks use parametric modelling, which means changes made to one part of the model will be automatically updated in related drawings.
- Visualisation and Rendering: CAD software provides the opportunity to produce a photorealistic view of the final product before it has been physically manufactured.
- Simulation and Analysis: CAD Software comes with integrated tools for simulation and analysis, to check the designed product will perform as expected, and optimise where appropriate. Design engineers can test the performance and endurance of the product under real-life conditions.
- Automation and Customisation: As complex machinery is designed to perform specific tasks; automation is a crucial tool used by our designers to enable efficient modelling and draughting work. Customising the tools in CAD packages used, allows Twenty20 Engineering to ensure repetitive tasks are automated. Helping to reduce design timescales.
Translating Ideas into 2D Sketches to 3D Designs
The conceptualisation process starts with sketching out ideas on paper, sketching concepts allows our designers to freely explore different concepts as at this stage technical details are ignored. As each product is developed to serve different purposes, it is essential to determine key elements to be included in the design as per the client’s specification.
Selecting the appropriate design software is made at early stage depending on the desired outcomes of the project. CAD Software is divided into many different categories, such as 2D and 3D, all perform a similar purpose of developing a concept into a detailed design. It is essential to be able to determine which software suits the project at the start. Broadly speaking Twenty20 Engineering using the following software for these types of projects
AutoCAD: This is a 2D draughting tool, mainly used for construction and architecture to create floor plans, elevations, and section details. We also use it for PID drawings for Mechanical Electrical and Plumbing (MEP) drawings.
SolidWorks: This our 3D design package used for modelling and draughting complex machinery with moving parts, as well as detailing all our CNC machining and Sheet Metal Fabrication Projects
Tekla Structures: This a 3D design package used for structural steel detailing, which we use on projects such as gantries, mezzanine floors, staircases and balustrading and other secondary steel items.
Converting Concepts to 3D Models
- Conceptualisation: This process can be started by defining the key elements which need to be represented in 3D CAD models. Sketches which have been generated can be used to visualise the models.
- Choose 3D Modelling Software: in the Engineering Sector, different software is available for developing design ideas such as SolidWorks, Creo, SketchUp, Revit, Fusion 360, CATIA and Tekla.
- Block Out Basic Shapes: Simple geometric shapes which represent the overall form of the concept developed can now be created, this is a similar step when creating a rough draft of the model.
- Establish Proportions and Scale: Ensuring the design has parts and components that are of the right proportions and scale to meet the design criteria. These sizes can then be tweaked as analysis of the model is undertaken.
- Refine the Model: implementing the analysis of the model, to optimise the design ensuring better performance and reduced costs.
Enhancing Concept Development with CAD
The Role of Precision in CAD Design
The key reason why industries opted to use CAD when designing products is the accuracy level which can never be achieved with manual drafting, the importance of precision can be seen in various aspects of CAD design.
Dimensional Accuracy
Design engineering precision is vital to ensure all components fit together precisely, to function as they are expected to. When modelling and manufacturing complex systems dimensions are crucial for their assemblies to be successful. This also allows the design engineer to apply appropriate tolerances to parts and components for manufacture.
Design for manufacturing
Precise CAD models help manufacturing engineers to produce the components with clear instruction on dimensions, tolerances, material, and manufacturing process to be used. minimizing chances of error and improving overall product quality.
Cost Efficiency
As the CAD software provides precision it automatically minimizes the likelihood of errors, which saves rework, and reduces manufacturing defects.
Tolerance Analysis
By analysing how each components interacts it is possible to set specific tolerances, to ensure the final product functions and can be assembled as expected.
Incorporating Real-World Constraints
Incorporating real world constraints is an essential aspect of engineering design, as this provides realistic 3D CAD models which reflect limitations present in the real-world environment. Here are some common real-world constraints and how they can be incorporated when developing a CAD model:
- Physical limitations: When designing a CAD model, it is essential to consider the physical limitations of the material, technologies available and manufacturing processes.
- Size and Space Constraints: Mostly the products designed are required to fit into a specific place with size limitations or allocated spaces. Designers at Twenty20 Engineering ensure that the model adheres to these conditions. By selecting appropriate tolerances to ensure ease of manufacture and assembly.
- Mechanical constraints: The product designed will be experiencing stresses, loads and forces, this is why our designers perform simulations and analysis to ensure the product can withstand real world forces.
- Manufacturability: Design engineers at Twenty20 Engineering optimize the design for ease of assembly during the manufacturing process (DfMA). 3D CAD enables us to visualise the assembly process.
- Cost Constraints: To maximize our client’s and stakeholder’s profit at Twenty20 Engineering our designers ensure to produce a design within budgetary constraints. Balancing the quality of the product and cost considerations.
- Assembly and Maintenance: When producing complex assemblies our designers prioritise ease of assembly, disassembly, and maintenance of the product.

Streamlining the Design Process
Reducing Design Iterations
Reducing design iterations is a crucial objective for product design engineering. At Twenty20 Engineering our design engineers have the goal to minimise the number of repetitive cycles needed to achieve a satisfactory and final design. To assure this some strategies are used to achieve this such as:
- Clear Requirements Definition: The design team always assures that product requirements and specifications are well defined and understood by the design team and clients from the start of the project.
- Effective Communication: Regular meetings, feedback sessions and updates always between our designers and client help to identify potential design issues early to avoid unnecessary iterations throughout the project. Having an accurate CAD model to present facilitates this process.
- User Testing and Feedback: When developing a product an end user is identified, to assure the product functions according to its purpose regular surveys and feedback are collected from the end users’ points of view. Which helps our design team to refine the design based on real world experiences.
- Clear Design Review Process: Each design phase consists of a detailed review to assess the product from the client’s and technical perspectives to ensure design requirements are met. This process of design review and evaluation helps to catch discrepancies and issues early, before proceeding to prototyping, manufacture and assembly.
Harnessing CAD Automation
CAD Automation has significantly increased the efficiency of our service, by reducing errors and increasing performance. CAD Automation involves using software techniques to modernize and accelerate the design process. Some of the techniques which we currently use include:
Parametric Design: Using parametric modelling technique to develop 3D models which are driven by constraints and parameters. This helps to easily modify and update the design by changing these. For example, when one part is changed all the documentation which references this part is updated automatically.
CAD Libraries: At Twenty20 Engineering all CAD models are stored and maintained regularly. Our library consists of design templates, components, and parts. This helps our designers quickly access the models and keep a record of all parts created. Where possible and suitable this library can be used to cross pollinate projects, ensuring a faster design process.
Data Management and Revision Control: CAD data management and revision control of a project is a system which tracks changes, efficiently and most importantly ensures all colleagues are working on the latest design iteration of a project.
Integrating CAD with Other Tools
CAD design software can be integrated with other areas of a project such as performance analysis, manufacture, logistics and production planning and tracking. Some common areas where twenty20 engineering has made use of this integration include:
- Computer-Aided Engineering (CAE) tools: Recent CAD packages include multiple CAE tools such as finite element analysis (FEA), computational fluid dynamics (CFD) and other simulation tools. Having access to these tools helps our designers to analyse and validate structural integrity, thermal performance, fluid flow, airflow and more.
- Product Lifecycle Management (PLM) Systems: PLM software helps our project team to track the entire product lifecycle, from designing stage to manufacturing and maintenance. This also helps with design updates and changes and feeds through into the revision control system.
- Virtual Reality and Augmented Reality Tools: VR/AR application tools to visualise and interact with design models in an immersive environment. This helps with design reviews, end-user assessment and collaborative design sessions.
- Material Selection and Library Tools: Having access to an up-to-date material library containing material information, makes it easy to select materials by reviewing each materials property against the design requirements and increase product quality. For example, optimising the material choices in a design can extend product life times in harsh environments. This is also an essential step when carrying out performance analysis of complex parts and assemblies.
Analysing and Simulating Concepts
Virtual Prototyping with CAD
Various design concepts are developed using virtual prototyping which makes it easy to quickly explore concepts. Concept exploration helps to select and iterate different ideas and solutions proposed. 3D CAD models enable the designers to visualize the product from specific views, zoom in on specific areas and determine how each component will interact with one another. This makes it very easy to spot clashes and part interferences.
To verify the developed design against the specification and requirements, virtual prototyping allows testing of the design under different circumstances. Whether by undertaking performance analysis or motion studies of moving parts. This helps to narrow down the field of potential ideas and produce a single finalised design.
Virtual prototyping has significantly reduced the need for products to be manufactured to be tested, which leads to shorter development cycles. Providing time and cost savings associated with this type of development.
Simulating Real-World Scenarios
Create Accurate 3D Models: 3D models are developed which represent accurate physical systems, including geometry, material properties, motion, and boundary conditions. As each product is designed and developed to perform specific tasks, realistic loads and constraints are defined, to undertake performance simulations. To do this simulation parameters include mesh density, time steps, joint motion must be defined and setup.
The simulation will display the behaviours of the design under different conditions.
By running the different types of simulation different sets of data can be collected and analysed. This is to check that the design performs to the requirements of the specifications of the customer, and then be optimised appropriately should the design over or under perform.
Ensuring Feasibility and Functionality
An initial project start up meeting with clients helps to establish clear and comprehensive design requirements and specification. This stage includes understanding the purpose of the product, performance criteria and constraints of the design. Regular project meetings and communication with the customer ensure the design’s development is in the direction clients expect. Allowing any unforeseen problems to discussed with potential solutions explored.
It is crucial to assess and identify potential risks associated with the design, such as safety concerns, technical challenges, and the manufacturability of the components, to enable a successful outcome for the design project. When considering the product, it also necessary to explore and assess the product’s long-term viability, factors such as repair, maintenance, and end-of-life disposal. Great products and the best designs have had a holistic approach to engineering applied to them, to ensure as many potential pitfalls have been designed out from the start.

Visualising the End Product
Photorealistic Rendering in CAD
A good quality 3D model is required for a brilliant photorealistic render and final image. To ensure the 3D model is of good quality it must be accurate, structured properly, has correct dimensions and includes all the complex details.
Realistic materials and textures are required to be applied to the 3D models before rendering can take place. Other factors must be considered to ensure a high-quality outcome such as the virtual environment, light source, light transmission, and diffusion, as well as the reflectivity, roughness, transparency of surfaces. More basic properties such as colour of components, will also be determined.
To improve the visual presentation of the product, the render settings will be adjusted to best showcase the 3D model being displayed. The final settings to be considered are the resolutions, and definition of the image to be created. It is important to balance the desired quality of the image with the computing power and time taken to generate the rendered image. This is a balancing act, although longer rendering times generally improve image quality this is not linear and valuable time can be lost for not much reward.
Showcasing Concepts to Stakeholders
Visual presentation is a crucial part of the project, it is important to showcase the design with visually realistic images and animations, high quality CAD models and technical drawings used to illustrate key features. Motion analysis is used to demonstrate the concept’s functionality, at this stage a presentation to the clients is beneficial as this motion study shows how the design overcomes solves specific challenges. This is a key moment in a products journey to becoming a reality and allows the designers to unveil the product in its full glory to the client. Although they will have been regularly involved and consulted, they may not have seen the design in its entirety.
The Impact of Realistic Visualisations
Realistic visualisations enhances and provides a clear and understandable representation of design concepts, which makes it easy to communicate complex ideas to clients. Realistic visualization of the products portrays a clear image of how the product will look once it is manufactured. This helps our clients to make a firm decision and be confident the design developed will solve their problem.
Around this time working prototypes can be produced and tested to provide a better understanding of the form, fit, feel and function of the design, where appropriate. Some design may be to big or bespoke to do this, as such scale models or sections of the design will be prototyped. Working prototypes can also be tested, to gain real world data to corroborate existing simulation data, this helps to build confidence and trust into the design.
Refining and Revising
Regular checkpoints are conducted to provide complete client satisfaction, from the beginning of a project till its completion. To ensure this the team at Twenty20 Engineering conduct weekly meetings to gather client feedback and demonstrate it has been implemented.
All Feedback is documented as the design process is a continuous improvement to the product. As feedback is received it is documented along with our designing team’s response and action plan. This helps to keep a record of changes and decisions taken over time, to ensure the decision-making process has been transparent.