3D Printing: An Introduction
In the future everything will be 3D printed. Or so we are led to believe. Like most of the science fiction-esq technologies I grew up with: robots, hoverboards, traffic lights that play music to you– 3D printing is slowly becoming a reality. So we might as well make an attempt to understand it…
I’m going to kick off this series by stating the obvious; however 3D printing has a more specific definition then you might expect. It’s the process of digitally driving the creation of a physical three-dimensional model by “printing” a succession of layers on top of one and another to build depth.
It’s a definition that’s analogous with the way a 2D digital printer works; line upon line of pixels, each one after the other on a page. This analogy extends a little further; as it excludes techniques that achieve similar results like screen printing and stenciling.
Similarly 3D printing does not include CNC machines and robot assembly, which although digitally driven that effectively use tools to hune objects. This is why the common term “3D printing”” is more technically known as Additive Manufacturing; the process of manufacturing by continuously adding (not official definition)!
I have come to think of additive manufacturing as the finite element method of creating.
Its strength is that it is generic: it might not always be the best way to do something, but it’s the only way to do anything. You can design any structure using FEA; yes there might be”quicker” ways- simple beam theory and the like. And that’s the same opportunity AM offers; a “general solution” to the making problem.
I’m going to talk about the different printing methods with their advantages and disadvantages, and take a look at the current attempts to bring the fledging technology to construction in later posts. For now I just want to dwell on some of the opportunities 3D Printing offers civil engineering.
The most outlandish is the dream that well simply print our future buildings and infrastructure out in there future. Whilst that sounds a little ambitious, even to me; it outlines the possibilities on offer. The most obvious in that example is the robotised workforce; effectively making our site safer and construction much more controllable and predictable.
3D printing allows you to create advanced geometries with a high precision. This gets architects excited as it opens up previously impossible options to them. However for engineers this means no more deliveries (print components on site), much smaller tolerances less faffing on site- imagine printing rebar cages!
Finally by definition AM has little to no waste; every piece of material used must end up in the structure- or be later removed by another process (i.e. temporary works). For an industry that regularly tops the wastage charts, this is not something to be sneered at.
Of course there are some challenges, and I’ll get round to those as well…