“When designers think about manufacturing a product, it’s natural to revert to well-known processes like Injection Moulding, Vacuum Forming, Sheet Metal or even 3D printing. Unfortunately, few consider using extrusion design, a process that can often better satisfy their brief requirements, improve the functionality of the product and cut manufacturing costs. In layman’s terms, extrusion design is the “toothpaste tube” process – a metal billet is forced through a die, creating a length of uniform cross-sectional material. There is a perception working with extrusions can be limiting as you’re effectively working in 2D, however we have seen this to be quite the opposite with some of Blender’s recent products. We think Aluminium Extrusions are an unsung hero of modern design and it needs more attention, so in conjunction with Blender Design, here are 5 of the biggest reasons why you should consider using Aluminum Extrusions to optimise your product design.”
Murray Clark – Key Account Manager: Altus
LOW COST CUSTOM TOOLING
The biggest misconception about utilising extrusions within a design, is that the designer is limited to the standard profiles offered by the manufacturer. Custom production-ready tooling is surprisingly cheap, only costing a fraction of injection mould tools, yet still offering control over your design intent. Compared to processes like injection moulding, with large upfront investment, this can be a way to reduce your per-unit cost and overall investment when exploring new product development.
When designing the Visitor Rego Kiosk, the extrusion design was the first part to be signed off and sent for production. The first off-tool samples were used to produce a functioning prototype, while the remainder of the parts were being fabricated from sheet metal and plastic. This allowed flexibility to continue to refine the design as required without the need to modify the extrusion design. This takes careful planning and consideration, however if done properly can save a large amount of time and costs, getting your product to market faster as well as adding an element of completion and final function to the prototypes, which could be hard to achieve with other manufacturing processes.
REDUCE ASSEMBLY TIME
If you were to fabricate your product entirely from sheet metal, disadvantages arise in the cost of human error and additional fixings such as PEM inserts for assembling parts and building the product. Aluminium extrusion design can remove many pain points, by reducing the complexity in manufacturing and building it into the extrusion design. For example, features such as screw ports, slots for T-nuts, clipping features and friction-fit fixings can be included in the design from the outset, resulting in a system that can be built more like Lego.
When damage occurs, or the product nears its end of life, extrusions can be easily removed, replaced and recycled for an incentivised premium, since the material carries a high raw value. Similarly, the tooling dies used to create the extrusions can also be melted down and reused to make new tools – ensuring far less material wastage in the product’s lifecycle.
Extrusion design has a large degree of modularity – it unlocks the power to grow your product in one axis and create multiple products with the same profile. By carefully considering your product and the required features to make it adaptable, the economies of scale can extend with future products, which would continue to utilise the initial tool. With a little foresight, extra features can be added to an extrusion that may be superfluous to the initial product requirements, which may be used at a later date in a future product variation.
To optimise the product, you can also combine extrusions with parts made through other methods. For example, creating injection moulded end caps to finish off the open end of an extrusion. Modularity also assists in more comprehensive servicing of parts as required, due to faster disassembly and reassembly. A well designed extrusion can be used throughout a product range to establish a cohesive brand language, all from a single extrusion tool.
Designing for aluminium extrusion can further optimise your design by increasing its strength to weight ratio; 6061-T6 grade aluminium can be over three times stronger than 304 Grade Stainless Steel. Blender Design can utilise finite element analysis (FEA) to assess a product’s strength requirement and load bearing capabilities to more accurately engineer a design and specify material grades that are fit for purpose.
Aluminium sections can be easily machined, bent or welded to form your product – being a softer metal this will take less of a toll on tools and can prolong your machinery life. The final machining stages can also allow for continual variation and refinement on you product, perhaps re-designing or adding function via the machined elements in order to extend your product lifecycle while still utilising the same extrusion and not require re-tooling.
Once extruded and processed, the aluminium profile becomes oxidised, naturally forming a protective surface layer across the profile. This alone can provide huge cost savings on post processing and finishing. Should the design require further protection or visual enhancements, post processing methods can offer a wide range of surface finishes and colour options, the most common being anodizing and powder coating, both offering their own unique advantages and disadvantages. As a further customisation, laser engraving is a method that can be used to add design detail or visual elements to a part, this could include branding or be as simple as part numbering.