Engineers in the US have created a prototype 3D printing platform with adjustable metal pins that negate the need to print excess support structures.

Many additive methods rely on printing additional support material in order to maintain part integrity during the manufacturing process, particularly for complex components. These excess structures must then be removed and the part finished by hand, something that can result in shape inaccuracies or surface roughness. Furthermore, the additional material can often not be reused, leading to increased waste.

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The new platform, developed by scientists at the USC Viterbi School of Engineering, features programmable, dynamically controlled metal pins to replace the printed supports. According to the researchers, testing of the prototype demonstrated around a 35 per cent saving in the materials required to print certain parts.

"I work with biomedical doctors who 3D print using biomaterials to build tissue or organs," said Yong Chen, professor of industrial and systems engineering at USC. "A lot of the materials they use are very expensive­-we're talking small bottles that cost between $500 to $1000 each."

"For standard FDM (Fused Deposition Modelling) printers, the materials cost is something like $50 per kilogram, but for bioprinting, it's more like $50 per gram. So if we can save 30 per cent on material that would have gone into printing these supports, that is a huge cost saving for 3D printing for biomedical purposes."

Similar concepts have been trialled in the past but have relied on individual motors to raise each of the mechanical supports, resulting in energy-intensive products unsuited to large scale manufacturing. The new device works by running each of its individual supports from a single motor that moves a platform. As well as savings on materials, the new platform promises significant savings on time.

An example of how dynamic pins can reduce the need for 3-D printed supports (Credit: Yong Chen)

"When you're 3D printing complex shapes, half of the time you are building the parts that you need, the other half of the time you're building the supports,” said Chen.

“So with this system, we're not building the supports. Therefore, in terms of printing time, we have a savings of about 40 per cent.”

According to the team, the system could be easily adapted for large scale manufacturing in the automotive, aerospace or maritime industries.

"People are already building FDM printers for large size car and ship bodies, as well as for consumer products such as furniture,” Chen said.

“As you can imagine, their building times are really long--we're talking about a whole day. If you can save half of that, your manufacturing time could be reduced to half a day. Using our approach could bring a lot of benefits for this type of 3D printing."

The research is published in the journal Additive Manufacturing.