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The Legendary Nylon Warriors of Lund

Reminiscent of the terracotta warriors of Xi'an, a veritable army of 3D printed busts is now poised, ready to protect Lund University.

During Kulturnatten 2015, an annual event in Lund that celebrates arts, culture, and science in Lund, Sweden, the School of Engineering's division of Product Development put on display an impressive array of 3D printed objects to demonstrate what the technologies are capable of. During the event, over 120 children and visitors had their heads 3D scanned in order to create mini-me figurines of themselves. Some of these were printed during the course of the day, but the bulk of them were printed a few days later on the university's new selective laser sintering system, that allows parts to be printed in nylon material.

Here's a brief explanation of how it all went down:

The visitors were scanned using the 3D Systems iSense 3D scanner, which is a little gadget that clips onto an iPad and transforms it into an easy-to-use 3D scanner. Each scan took about a minute to perform and produced files ready to print. Here's a picture of scanning expert Per Kristav performing the 3D scanning operation on the lovely Cilla Perlhagen, course administrator to the Stars:

In software, each bust was scaled to be approximately 6cm tall, and the files were then all nested together so as to print as many as possible on our 3D printer at once. Each bust was also embossed with the persons name on the underside so we could keep track of all the heads. We were able to print approximately 40 heads in each build (though we were also printing other student parts at the same time).

The SLS 3D printer works by spreading a thin layer of nylon powder, and a laser is used to "draw" each slice of the model onto the powder. Wherever the laser hits the powder, it is melted into solid plastic. The print platform is then lowered by 0.1mm and another layer of powder is spread on top of the first, and the process is repeated until all the slices of the model have been done. The machine used for these prints was an EOS Formiga P110 Selective Laser Sintering System. Here's a picture of one of the slices being melted by the laser. Each contour that you see is a slice of a particular bust being printed:

Once the build is complete, the block of powder is removed from the machine, and the real fun begins. You get to play archaeologist and dig through the powder to find the parts you are looking for:

And, once you have your part, a quick sand-blasting operation to clean off any lose powder stuck to the part and, voila! you have yourself a mini-me:

And here's a little view of our army from the back:



copyright 2011, olaf diegel