Mould cavities and channels

Design for manufacturing guide and tips

Product design of hardware is hard, but it can be profitable with proper design for manufacturing DFM optimisation.
Jane Lai
Jane Lai Photo

Since product designers work on product designs for various niches, from electronics to medical supplies, it is not an exaggeration to say that they play a major role in shaping the world we live in. However, the competitive global market can be less focused on optimisation for manufacturing (DFM).

Functionality above all

It may seem obvious, but functionality is something many product designers overlook. In order to make their product designs stand out on the local or global markets, many product designers fall into the trap of over-engineering everything.

This means they make a design that is aesthetically pleasing with all the bells and whistles but does not function the way it was intended compared to a simpler version. A simpler design that suits its purpose perfectly is much better than a complex design that does not do its job any day. Luckily enough, over-engineering can become apparent in the prototype phase and fixed before it is too late.

Being specific

Pleasing everyone is an impossible task – it would be unwise to even try. This may sound negative, but trust me, a product that is tailored to suit one niche will sell better than a product that tries to be the Jack of all trades. Figure out what market you are aiming for, agree on a specific design and stick to it!

Build on existing products

This does not mean one should plagiarise other people’s work. However, one should just look at the existing market and learn from the products that have sold well – they have sold well for a reason, right? As a product owner, you do not always have to make something completely new. In fact, most of the design projects and prototypes are based on upgrading existing products rather than coming up with entirely new ideas! A wise man (Isaac Newton) once said, "If I have seen further than others, it is by standing on the shoulders of giants."

Design for manufacturing, sometimes are also referred as design for manufacturing and assembly (DFM/DFMA), describes the practical method which optimises the design for the collection of mechanical parts within a product, so that they can be easily produced in the factory. Some general considerations are concerning this process can be:

✔ To find an innovative design which improves production effectiveness
✔ To choose feasible material which meets customers’ requirements
✔ To choose a proper type of manufacturing process

Let’s make a guess. How much influence will this design process have over product cost, quality and cycle time: 30%, 50%, or 70%? The answer can probably go to 70%. Around 70-80% of the cost, resource overhead and product development issues happened because of a poor design process, while the actual manufacturing process attributes only the rest 20%-30%.

Maximising profitability of mass production encourages larger companies to integrate the design for manufacturing process into their early-stage product development. For greater success, some of these companies would outsource an experienced third party for better overall optimisation. There are some steps which eligible design team should provide for the DFM plan.

Prioritise design optimisation

Is the biggest goal of the optimisation process to reduce as much labour cost as possible? Are the companies aiming at achieving functionalities of products regardless of cost?

Generally, companies would have a list of tasks that they want to achieve in mind. While a good design team would help adjust and translate these tasks into several objectives and prioritise them. A simple example is a design for high-end use would address more of the functionalities and than cost. Setting up with clearly defined purposes at the beginning of the project will help identify the scope of the project. It also helps better manage feasible resources.

Utilise effective communication

The biggest challenge in DFM is usually communication. Communications take place throughout each process. The small agile team can fast respond to changes and minimise the chance of misunderstanding. In addition, clear written communication would be vital. To successfully generate the optimal design, an experienced team would address them all. They would be able to demonstrate objectives orally as well as in written documentations such as DFM reports.

This detailed documentation would then help companies develop instructions and specifications which are understandable by workers in production lines.

Identify main elements

Good DFM requires designers to effectively decompose a complicated product. This indicates that they need to identify the number of components that will need to achieve the functionalities and the relevant assembly process.

Designers with expert-level of knowledge would facilitate this process. Especially when nowadays entrepreneurs may own factories and business located around the globe. Teams that are familiar with the industry and global market will not only optimise suspect/questioned components and processes, but also give suggestions about vendors selections.

Select proper materials

Proper materials can have a greater impact on cost and efficiency than thought. In this stage, the design team would choose materials based on the functional requirements, as well as optimal manufacturing purpose.

One question for considerations can be: whether it is necessary to use different materials in different parts of the products? A more advanced service can be choosing material suppliers by performing cost and quality analysis for customers.

Consider environmental factors

Environmental factors such as pressure and yields, temperatures are also taken into considerations during design. To build a robust design for supply chain, shipping time may also be crucial when customers own a long supply chain. Insertion and interconnection parts may be minimised since smaller parts may fall apart during shipping. Apart from that, designers would perform several testing methodologies on prototypes to avoid risks as well.

Use existing technologies

The word “design” in DFM means more than creating products with fancy technologies. This is because the design team always take the whole manufacturing chain into considerations. Most of the time, as mentioned above, companies will choose various supply chains around the world.

In these cases, the technological gaps between these countries’ factories matter. In other word, designers should have a comprehensive investigation of existing technologies. As a result, an outstanding design should be those who successfully cooperate with the existing feasible resources. It should be applicable to most of the manufacturing lines that customers would involve.

Save money

In a general mass manufacturing process, companies usually put loads of effort to reduce the production cost. As stated above, a proper DFM process highlights the importance of creating products from feasible materials. To achieve this goal, strengths and weaknesses of different materials will be listed for further analysis. This process will often help manufacturers find the materials with a lower production cost than expected.

Sometimes, products with delicate mechanical parts will require manual assembly. In this case, more parts mean there will be a higher gross labour cost. DFM’s principle of minimising the number of mechanical parts addressing design with simplicity. Designers can easily achieve cost-effective design when conceptualising designs with some DFM principles. Experts suggest that good design sometimes can dramatically reduce the total product cost at up to 50%.

Save time and energy

One methodology in DFM points out that the necessity of designing in a way that small parts of the product can easily be attached to each other. Another methodology is to design products with maximum tolerance.

A lot of product parts may require operations such as inserting with alignment. A design with tolerance will ease the precision prerequisite for your manufacturing line, therefore save more time and energy. Apart from that, DFM also indicates that designers should understand how to deploy proper modules for various manufacturing purposes.

These methodologies all aim at providing a solution with minimal back-and-forth designs compared with the past. It will be worth it by spending 80% of your effort on the designing process.

Ensure higher product quality

A successful DFM process not only ensures product manufacturability, but also guarantee product quality. Before and along with the entire design and testing procedures, we will need to perform a large amount of research, including investigation of previous quality issues. The quality products will build a solid foundation for a company’s growth and attract more customers.

To sum up, DFM/DFMA usually aims at shortening manufacturing time, reducing cost on labour and material by utilising a set of design standardisation. When entrepreneurs turn their eyes to mass production, it is no longer feasible to isolate the manufacturing process and the product design process.