With product development costs taking such a large lump of assigned budget, every design team will be keen on making sure that products are designed right the first time and encompass the original ideals and intent. However, too many products go through the design phase without proper thought as to how it is actually going to be made, and it is very common for finished assemblies to go through at least some level of redesign to enable ease of manufacture, which just piles cost on a product that may already have swallowed a large proportion of allocated resources.
Design For Manufacture (DFM)
Designing with manufacture in mind – otherwise known as Design For Manufacture, or DFM – is an extra skill that evades many engineers, but is essential to ensuring that a new device can be made efficiently and in the most cost-effective manner. Prior to DFM being almost universally adopted, the ethos in the design office was one of “we design something and production builds it,” and almost invariably production or industrial engineering would have the headache of figuring out the best or most cost-effective way of manufacturing the device once fully designed.
DFM turns that thinking on its head and puts production engineers in the design meetings, from concept upwards, with the view to creating a production-ready design from the very beginning. DFM brings certain skills and a down-to-earth attitude that may sometimes be lacking in a design team, and highlights the issues that can be forgotten. Production engineers can advise on many aspects of a new design, including:
The use of formal production processes
The designer may have grandiose ideas of carving parts of their design from solid blocks of steel with a focused laser beam, which sounds exciting but is completely impractical and no doubt hugely expensive. Manufacturing engineers bring things back to a practical level, and point the design team toward common and affordable processes that will be both easy to tool up for and can be grasped by production staff. By using standard production processes such as turning, milling, and drilling, rather than complex and expensive alternatives, manufacturing engineers help determine what is appropriate in regards to actually making a design.
Avoiding slightly asymmetrical parts
There is little more annoying – or costly – than making two slightly different parts instead of one part twice. Avoiding subtle changes in parts will remove the possibility of a product being assembled incorrectly because a production fitter has not noticed the small difference between parts and mis-assembles the device. Only make things different if you have to, and if you do, make sure that they are noticeably different to prevent misunderstandings.
Poka-Yoke
Allied to asymmetry, Poka-Yoke is a concept first fully realised in Japanese industry where a part can only fit in a particular way, preventing mis-assembly. Poka-Yoke relies on some design constraint which will only allow assembly in one way. Household power sockets are designed so that the electrical connectors cannot be reversed, and HDMI computer connectors are shaped so that they can only fit into the corresponding socket one way round. Poka-Yoke is a simple device that ensures parts are assembled in the correct orientation and order, and while it is an immensely powerful tool, it must be planned in at the very start of the design phase to make it completely effective.
Design production tools and fixtures as you go
Rather than creating a new design and producing tools to enable its manufacture, DFM aims to build up specialist tooling as it becomes apparent so there are a full suite of jigs and fixtures by the time the design is complete. This means that prototype production can start almost immediately and the road to full manufacture is foreshortened considerably.
DFM is not only desirable, but essential to making a product that is easy and cost-effective to manufacture. Involving manufacturing engineers right from the outset of a new design will not only reduce costs, but will also shorten time to full production and eliminate almost all of those costly mistakes that eat into profits and credibility.
Pivot International is a product design, development, and manufacturing firm with extensive experience in the medtech industry. If you are interested in engineering a new product or updating an existing product, contact us at 1-877-206-5001 or request your free consultation today.
