Design for Manufacture
Design for manufacture (DFM) is incredibly important, even in additive manufacturing! But don't worry, this is where Plunkett Associates' knowledge and expertise can help.
It’s all about taking full advantage of the selected manufacturing process whilst at the same time engineering the part(s) to suit the process and minimise cost.
Issues can range from a simple chamfer around a hole that requires an extra setup when CNC Machining, to the way in which a hole is created during injection moulding that may require an additional side action. We are able to help with all these issues and more.
As the manufacturing method is frequently undecided when a client initially approaches us, support to make the necessary changes becomes an important part of the design service we supply.
Additive manufacture is bound by a set of design rules in the same way that ‘conventional’ manufacture is, they are just different rules.
Designing for manufacture helps to prevent a substandard end product
Understanding these rules, or designing for manufacture is as important today as it has always been. Ignore the rules and you will get a substandard product, or at best you will pay over the odds for something that could be produced for less. We should know – we have been involved in additive manufacturing processes for 30 years so our knowledge and experience is second to none.
So design for manufacture is just that. It’s designing with a manufacturing methodology in mind, such that features are created in ways the process can replicate without difficulty. (As difficulty usually means additional cost!) This can range from simple issues like the selection of a radius used in a fillet, to more complicated issues such as how to anchor a boss to a thin wall without compromising the tooling or creating sink marks on an aesthetic surface.
Process choice will depend on quantity, material, geometry and aesthetics
How to select a process then? There are several important factors; probably one of the most significant is the quantity of parts required. Then there is material, size and complexity of part, and what kind of aesthetic finish is required. All of these we can help you with.
The problem that frequently occurs with quantity is that marketing do not divulge (that is short for ‘do not know’) quantities, especially in the launch phase. So whilst the expectation might be 5 – 10,000 per year, the first batch might be 50 off. The natural desire is then to try and postpone any capital expenditure on tooling until quantities begin to rise. This can lead to different technologies being used initially that are not optimal for the design.
Adapting designs to suit the required process
There are ways of doing this, but frequently they will require small modifications to the design to improve the economics or sometimes make it a feasible proposition at all. This is where we can help as not only do we distort the conventional quantity/process relationships, but we also specialise in adapting designs to suit the required process.
If the process is injection moulding, then we have developed four categories of tooling, to suit different phases in the development programme. Please take a look at our tooling section – you may be suprised at some of the options!
We run Moldflow, the industry leading software package for simulating moulding, so that we are able to identify many potential issues before leaving the computer screen. These are issues that don’t just affect the ability to mould your part, but also the quality of the resulting part, both physically and aesthetically.
Early communication makes good economic sense
Using such a variety of processes gives us incredible latitude to find the optimum solution for a project and ensure the design is suitable. However, appreciating that manufacturing may require some modifications emphasises the point that early communication makes good sense. Perfecting a design before opening discussions can quickly unravel days of work – so talk to us now!
Bottom line; whether the production method is additive or subtractive, prototype or volume, talk with us to understand your options. Then we can work with you to create a design that meets your requirements, yet is straightforward to manufacture. After all, that is what Design for Manufacture is all about.