Traditional manufacturing techniques, although perfect for many application, often have prohibitive factors to small scale use. Injection mouldings require expensive tools, castings don’t provide a great deal of accuracy and are labour intensive and CNC machining creates waste material which increases the cost.
All of these techniques also have restrictions for the designer. You have to think about how to get the finished product out of a mould or die when it is cool or how the machine tool is going to get to the area you want machining out, all of which restrict freedom in the design process.
Additive manufacturing provides the tools to get around all of these issues. 3D printing or rapid prototyping are a colloquial terms that cover a host of different processes. Essentially they describe the process of making one off objects by means of additive manufacturing. The most common forms of 3D printing are FDM, SLA and SLS.
The FDM or Fused Deposition modeling, involves small precise nozzles laying down tiny beads of heated material which fuses together as it cools. Imagine a tiny tube of toothpaste squeezing out in layers to form a shape.
SLA or Stereolithography uses a pool of liquid material which reacts to UV light. Effectively an image is projected onto the liquid which hardens a fine layer. The bed holding the liquid moves a tiny amount and another layer is created, which fuses to the first. The object is built up layer by layer until it is complete.
Finally SLS or Selective laser Sintering uses a bed of powdered material. A laser traces out a shape and melts the powder into a solid. Once one layer is complete the bed moves down slightly and another layer is traced out, which fuses to the first. Once complete the part is removed and any excess powder brushed off. SLS is the process that we use mostly as it produces a fine surface finish, accurate detailing and enables the creation of metal one off parts.
By using this technique we are able to think of an idea for a frame component, model it on the computer and send that data directly to a SLS machine to produce the part. No tooling is required and because of the way it is made forms that could not be manufactured by other means are possible, such as integral moving parts, objects captured within other objects or as simple as ready mitred and personalized fame bridges.
Where will this technology lead? There is a lot of buzz around the processes involved, which is leading to generous investment into research and domestic FDM printers are becoming affordable. The reality of it is that small scale artisans will have the ability to produce items that previously would have cost too much or taken too long to produce. For us that means being able to offer truly customized finishing touches to our frames and components. We are currently using SLS to produce frame components and are also looking at a line of customizable components.
The true breakthrough here is the liberation of designs. An idea that may have sat in a file due to lack of investment, could now be offered up to the wider public as 3D solid model data, to be downloaded. They can then have it manufactured at anyone of the online 3D printing services to receive the finished product.