Recent articles [1-3] emphasized the interest of 3d printing for scientists. In addition to pedagogical activities, during which students experience 3d models, scientific research can benefit a lot from such a technique. Scientists may build complex structures and may dream about new possibilities for testing their ideas.

A 3d printer (Mojo, STRATASYS) is now used in our lab. Examples of 3d applications are :

• Granular matter : to design grains (see pictures above) with specific non-convex shapes for interlocking, providing unusual granular properties. The morphology of grains can also be determined by measurements of real particle systems.
• Self-assembly : to produce synthetic floating bodies for testing capillary attraction between small objects suspended to a liquid interface. The shape of objects will induce capillary multipoles for specific interactions.
• Microfluidics : to build complex microfluidic devices for creating encapsulated droplets or producing monodisperse bubbles.
• Foam : to create 3d complex rigid frames for trapping improbable (stable or metastable) soap film structures.
• Statistical Physics : to design specific lattices for playing with the granular counterpart of the Maxwell’s demon.
• Percolation : to print 3d fractal structures for testing fluid invasion and other physical processes such as diffusion.
• Complex fiber networks : to create frames for connecting complex digital microfluidics fiber-based networks.

Many more ideas are currently tested.

[1] J.N.A.Matthews, 3D printing breaks out of its mold, Physics Today 64, 25 (2011)
[2] M.D.Symes et al, Integrated 3D-printed reactionware for chemical synthesis and analysis, Nature Chemistry 4, 349 (2012)
[3] N.Jones, Three-dimensional printers are opening up new worlds to research, Nature 487, 22 (2012)