Modified laser cutter creates 3D objects from multiple materials

A team of researchers from Rice University have created a 3D printer that uses lasers in order to create more complex objects than traditional devices from a range of different materials.

The printer uses a modified, commercial-grade CO2 laser cutter to create OpenSLS, an open-source, selective laser sintering platform that can print intricate 3D objects from powdered plastics and biomaterials.

Ian Kinstlinger, study co-author, said: "Designing our own laser-sintering machine means there's no company-mandated limit to the types of biomaterials we can experiment with for regenerative medicine research."

The researchers say that the system costs around 40 times less than its commercial counterparts and allows them to work with their own specialised powdered materials.

One of the limitations with traditional extrusion 3D printing methods is that it cannot create structures with overhangs because it needs to layer the plastic onto an underlying structure. The OpenSLS system is claimed to work differently, the laser shines down onto a flat bed of plastic powder and wherever the laser touches the powder, it melts it to form a small volume of solid material. By tracing the laser in two dimensions, the printer can fabricate a single layer of the final part.

Where commercial SLS machines generally don't allow users to fabricate objects with their own powdered materials, the Rice team’s machine is capable of this which helps researchers who want to experiment with biomaterials for regenerative medicine and other biomedical applications.

Jordan Miller, study co-author, said: "SLS technology has been around for more than 20 years and it's one of the only technologies for 3D printing that has the ability to form objects with dramatic overhangs and bifurcations."

The team showed that the machine could print a series of intricate objects from both nylon powder, which is a commonly used material for high-resolution 3D sintering, and from polycaprolactone, which is used to make templates for studies on engineered bone.

Miller added, "SLS technology is perfect for creating some of the complex shapes we use in our work, like the vascular networks of the liver and other organs."