A friend of mine and I both have a similar project in mind, the manufacture of custom footwear with our hackerspace’s shiny new multi-material 3D printer. It seems like a match made in heaven, a machine that can seamlessly integrate components made with widely differing materials into a complex three-dimensional structure. As is so often the case though, there are limits to what can be done with the tool in hand, and here I’ve met one of them.
I can’t get a good range of footwear for my significantly oversized feet, and I want a set of extra grippy soles for a particular sporting application. For that the best material is a rubber, yet the types of rubber that are best for the job can unfortunately not be 3D printed. In understanding why that is the case I’ve followed a fascinating path which has taught me stuff about 3D printing that I certainly didn’t know
I watch a dude who makes videos on just the wildest filaments out there and there are several that are either some kind of actual rubber but with other things mixed in to make it better for 3D printing, or that mimic rubber's various properties. In one video posted recently, he used one such filament to print Crocs.
I believe it was this one: https://youtu.be/J8PZWkjt65Q