Fast 3D Printing Technologies for Composites and Metal Gain Traction

          By Brian Orlotti

A team of aerospace engineers, armed with advanced 3D printing technologies they claim could increase print speeds by a factor of 100, took another step towards commercialization with a five minute pitch to a panel of venture capitalists and entrepreneurs at the Mecklermedia Inside 3D Printing Conference in New York City earlier this month.

Screen shot from the Orbital Composites video presentation at the Startup Competition, part of the Inside 3D Printing Conference, which was held from April 15th - 17th in New York, NY. In 2014, the event raised more than $6Mln USD for a variety of 3D printing start-ups including 3D Hubs and Wiivv Wearables. Graphic c/o Orbital Composites. 

Orbital Composites’ three new patent-pending technologies are meant to be used in the nozzle (known in 3D printing jargon as the 'hotend') of a 3D printer. These new technologies include:

Coaxial Extrusion - In coaxial extrusion, an extruder coats strands of carbon fibre (or other materials like copper wire or solder epoxy) in plastic before being extruded. As plastic filament enters the hotend, it melts and is funneled into a tube where another extruder adds a fibre directly into the centre of the extruded filament. The plastic and fibre bond while exiting the nozzle and then cool.  

This type of hotend can extrude pure plastic, pure carbon fibre or any combination of the two. 

Coaxial extrusion promises to greatly reduce print times by reducing the number of layers needed for an object. The massive strength of carbon fibre would enable an object to be printed in 1-2 layers instead of 5-10 layers using regular plastics. In addition, coaxial extrusion would enable electrical wiring and circuitry to be incorporated directly into the interiors of objects. In the aerospace industry, this could dramatically cut the cost of aircraft and spacecraft through huge weight savings and decreased complexity.

Capillary Injection Molding - Capillary injection molding combines traditional injection molding with 3D printing. In capillary injection molding, a carbon fibre-filled epoxy is injected into the voids of a printed honeycomb structure. This technique promises to increase build speeds by a factor of 10 or more. 

Active Molding Roller - In FDM-based 3D printers, plastic is heated in a controlled manner, but a printed object's layers aren't cooled in a consistent way. This inconsistent cooling can lead to layer warping (called "delamination"), which creates internal voids and adhesion issues in 3D printed objects. The active molding roller, described by Orbital Composites as a “heavy, steam-rolling radiator” compresses the extruded plastic, to remove the voids.  

The active molding roller allows for realtime error detection and correction, enabling a void-free internal structure and improved surface finish for 3d printed objects. The active molding roller could close the quality gap between 3D printed objects and traditional injection-molded plastic parts.

Rather than building their own 3D printer, Orbital Composites intends to sell their innovative hotends as 3D printer/CNC machine upgrades via original equipment manufacturer (OEM) channels.

Potential clients include groups currently investigating orbital manufacturing such as Tethers Unlimited (the developers of the SpiderFab orbital 3D printing system), Made in Space (the creators of a zero-g 3D printer now on board the ISS), and the Defence Advanced Research Projects Agency (DARPA).

This type of strategy has proven effective for firms like Taiwanese computer powerhouse ASUSTeK Computer Inc. (aka Asus). Asus began as a components supplier to desktop/laptop computer builders like IBM, Compaq, and Dell. Over time, Asus became an industry-leader and now produces many different products in its own right.

Brian Orlotti.

Should Orbital Composites succeed in obtaining funding, its products may further revolutionize the space industry, already undergoing its greatest changes in decades. 

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Brian Orlotti is a network operations centre analyst at Shomi, a Canadian provider of on-demand internet streaming media and a regular contributor to the Commercial Space blog.