Thinking savvy about CNC cutting
I happened across the TED ELEVATE warming huts project by Design Build Research institute. The arches play such a large role in defining not just the structure but the aesthetic of the structure. For someone who looks at projects like this from the fabrication perspective, components like these arches also constitute the largest amount of challenges, especially when trying to control for cost.
With the CNC process, the largest amount of cost comes from is time on machine. Put simply, the more a machine has to cut the more expensive things are. These arches are wonderfully thick so that presents two issues, one is time it takes the CNC machine to profile through the individual thickness of the workpiece. This is exasperated by the notion that there’s a few layers of individual work pieces needed to complete each arch. I’d also think that the overall shape and scale of the arches would have impact on the number of components needed to be cut.
That introduces a third area where costs originate – unloading and resetting the machine. While the machine isn’t generating income there, the people needed to do the switching of work pieces start generating costs. That cost doubles with successive arch layers. The shape of the arch also plays a part here by deciding the ability to extract as many pieces per workpiece as possible. If the job can only fit one component per work piece then there’ll be more costs associated with resetting the machine.
Obviously, all this really doesn’t have that much effect on smaller projects but when there’s large components and larger quantities like the ones needed for these shells, these sorts of things tend to start adding up rather quickly.
It’s interesting to talk about these aspects as it relates to the design of the structure. In the manufacturing world they call this engineering for manufacturing. In that world, the big shift is to engage manufacturing engineers who work to efficiently produce products well before the process of designing the product is complete. Perhaps this sort of thinking could also be useful for the more complex structures that can be now available with the preponderance of CNC machining available to architects and designers.
Knowing where costs come from in this relatively nascent market might go a long way to making more exciting things that much more achievable.
