WinSun, the Chinese firm that managed to one-up the competition in mega-scale 3D Printing have recently released a new set of pictures that highlight their latest large-scale structures. These humungous one-story to six-story buildings were printed using specially-formulated extruded cement, which were each made in separate pieces and lifted into place. None of the pieces, from what we can gather in the imagery, are actually acting as the primary load-bearing structure pieces, as rebar and more concrete have been added within the prints. Technicalities to the side – these are 3D Printed buildings! However, there are a whole lot of ‘so-whats’ to be accounted for.
WinSun didn’t appear out of nowhere. In fact, they’ve been in business for 12 years and have been pursuing printing methods for as long as Contour Crafting has been around. Their building material is made from a combination of ‘recycled construction waste, glass fiber, steel, cement and special additives.’
They have picked up deals with Tomson Group, a well-known Taiwanese-owned real estate company and are selling 20,000 units of their smaller houses to the Egyptian government.
Dude, Where’s my Freedom of Design?
As big and tall as these buildings are, none of them exude anything appealing or beautiful. They are straight, flat and completely plain. Once finished, the only indication that they were 3D Printed would be the finger-thick layer lines. Perhaps it’s just to appeal to the masses or simply taking the approach in baby-steps.
But really, it’s simpler than that: overhangs and complex forms are nearly impossible and represent a serious limitation of WinSun’s technology.
FDM with cement presents several problems: cement takes a while to cure, and using a faster curing cement is problematic because the nozzle becomes jammed. Thus extruding layers outside a fraction of the width of the previous layer means that the material will begin to droop and creep before it solidifies. One option is to go with thinner layers, but of course, that means a smaller diameter nozzle, and more layers means more time spent printing the equivalent volume.
These are the sorts of catch-22s that nobody in the 3D Printing Industry is talking about unfortunately; because it gets in the way of a great story. For what it’s worth, at least this guy made something interesting.
Productivity? Productivity compared to what?
One of the most misleading figures I noticed in 3Ders’ exclusive report on WinSun’s work was how ‘Productive’ their method was:
WinSun estimates that 3D printing technology can save between 30 and 60 percent of building materials and shortens production times by 50 to even 70 percent, while decreasing labor costs by 50 up to even 80 percent.
See, there is no explanation of what is really produced, and what this is compared to. If we were assuming that every part made with this 3D Printer represents 100% of the final house, then these figures would make sense. Buildings are the sum of a whole different set of machines, people and materials. If there was a machine that could do all of this with one material, one operation and one method, then these numbers would make sense. But as you can see in all of the pictures, rebar, aggregates and other cements are added to create the final building. Without being able to compare apples to apples, WinSun’s figures can’t be taken seriously.
Cement is still incredibly Carbon-intensive
For all their proclamations that WinSun’s 3D Printing methods and materials are environmentally sensitive, there’s a pretty simple explanation as to why they are not. Cement, pound for pound, still needs to be made via heating, mining and transportation, which altogether generates massive amounts of CO2. Even if recycled materials are utilized in the final product, that isn’t too terribly different from other methods that are already standard in the construction industry. So the question I would ask is: what exactly is so unique about their materials?
The very fundamental element of disruptive technologies is that they do more for less. 3D printing can, in many circumstances, do much more for less. However, if creating simple structures in a limited fashion and what could be a higher cost than existing methods is considered disruptive or innovative, then it probably is not.
While it’s impressive that WinSun has managed to raise 3D Printing to new heights (literally), you cannot see very much from the top with this particular extrusion method, at least, nothing that one could do with existing methods at equal cost. In addition, the total lack of actual evidence to back up some of these numbers may indicate that there is something missing, that perhaps if it’s too good to be true, it must not be true.