Alan Zerobnick is interesting not only in that he is 70 and teaching 3D printing to young shoecrafters, but also in his persistence to see that the shoes he produces are done so to absolute perfection--and that means embracing complete customization in each pair. In the '90s, Zerobnick created a software program to help with customization. A lover of technology, as 3D printing came around he wanted to use his files in fabrication. They were not compatible though, and after some struggling, he found CAD Exchanger--a software able to convert his IGES files using NURBS. Today, he is still teaching, but has added lessons in digital design and 3D printing to the roster. Read more at 3DPrint.com: http://3dprint.com/111713/70-yr-old-shoemaker-3d-print/