Going off the rails? How DfM optimises manufacturing processes

DfM, Design for Manufacture
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featured-insight-post-minIn a perfect world, problems that derail complex manufacturing projects would be identified at design stage. The main reason these problems are often identified too late is because the Design for Manufacture (DfM) process has either not been applied or applied too late.

When this happens the consequences are costly. As reported in Metal Working World Magazine, manufacturers spend 30% to 50% of their time fixing errors and almost 24% of those errors are related to manufacturability. At best, badly planned projects cause project costs to overrun into the millions, but at worse, lives are lost.

What, then, is the solution?

Stages of production in DfM

DfM is about de-risking the manufacturing process. Broadly, a typical manufacturing with DfM route involves a scoping stage, where the conceptual design and development takes place. Following the completion of designs, there follows a prototype and testing stage before the part goes to production. If a product is designed without the involvement of a DfM partner, oversights will quickly become apparent at prototype stage or hopefully, during a simulation process using CAD software - though even simulation isn’t foolproof.

However, all too often, mistakes are discovered at the build stage and when this happens it is essential that companies follow a rigorous process to get their projects back on track.

Back to the drawing board

Pushing through a poorly planned design without revisiting the scoping stage will likely cause costs to stack up. If you’ve identified one area for improvement, the chances are there are far more to fix. Every DfM partner you work with will have a different style of working but will essentially strive to fix your design by going right back to that original scope. Don’t be afraid to turn around.

While the following isn’t an exhaustive list, redesigning with a DfM partner will involve examining and refining the following areas of your design:

Education and knowledge transfer

At the Sarginsons Technology Centre, our Scoping stage may necessarily, for example, involve educating clients about the latest advances in die-casting technology, recommending alternative materials or build methods. It is essential that partners involved in this process understand the technology being used to build designs because designs are often created for a ‘perfect world’ and will not translate to the shop floor. For example, there are many guidelines that already exist for die-casting, but some parts do require specific treatment such as casting thinner walls or adjusting draft angles. This is particularly relevant when manufacturing products in fast-changing industries, like car manufacturing – specifically for electric vehicles. A DfM partner can get these details correct right from the start, but they need to be aided by your team. By later stages in the project, and certainly, if you’re experiencing problems with the project, you should have put together a group of people you trust to identify any other flaws in the design.

Geometry

As computer-assisted technology advances and machinery and tools are further developed, designs follow suit. Traditional guidelines, which exist everywhere in engineering, can be tested in order to create a new generation of parts with advanced capabilities. Wall thickness can be challenged, drafts can be altered, and potential flow problems can be identified early by a DfM process that combines the very latest knowledge of machinery and die-casting techniques with impeccable processing. Sharp intersections could be replaced by fillets, for example.

Flow and filling

Altering geometry has a knock on effect, of course, on flow, but a DfM process will accurately predict and plan for any filling problems that might arise ahead of production. This requires an incredibly in-depth knowledge of die-casting where partnering with a trusted consultant would pay dividends.

Easy-to-understand designs

Your designs need to be easily understood by anyone on the foundry floor. Different materials or internal, smaller components may not be obvious to everyone. It is, therefore, best practice to make different parts easily distinguishable. You could decide to use markings, labels, colour, or different packaging if they come individually packaged. Plans should be easily read and marked up clearly and consistently. While it might sound basic, easy-to-understand designs are crucial for reducing mistakes and keeping production costs down.

Die-casting is a highly specialist skill. And, with design determining 80% of final reduction costs, the best way to stop your project going off the rails is to implement DfM consultancy at the earliest possible stage. If you don’t do this then it’s worth cutting your losses and rolling stuttering projects right back to the start. In both these cases, the cost-savings cannot be underestimated and the Sarginsons Technology Centre, of which DfM consultancy is a significant part, was set up to deliver optimum efficiency in the manufacturing process.

If you’d like more information on how the Sarginsons Technology Centre and how we work with DfM, click here.