If you have any doubt that we’re living in the future, consider this. Defense contractors are building a 42-foot-tall printer that can print a tank hull. And a Christiansburg company has a major role.
The printing of tanks is something that Johannes Gutenberg did not foresee when he invented his printing press around 1450. And indeed, “printing” is something of a misnomer for this industrial process. Whereas the product of traditional printing is a piece of black-and-white or colored paper, industrial 3D printing sequentially deposits hundreds or thousands of layers of metal or plastic, building up a three-dimensional object of theoretically unlimited size. In the engineering world the process is called additive manufacturing.
The project was revealed on the official Army website, army.mil, on June 1, 2021. The Ground Vehicle Systems Center, based in Michigan, part of the U.S. DEVCOM (Combat Capabilities Development Command), announced plans to build the world’s largest 3D metal printer.
The monster printer, able to produce objects 30 feet long, 20 feet wide and 12 feet high, is expected to take 14 months to complete. It will be installed at the Army’s Rock Island Arsenal–Joint Manufacturing and Technology Center in Illinois. RIA-JMTC will be in charge of the project.
“Called the Jointless Hull project, the effort is being coordinated and led by prime contractor ASTRO America which will work together with subcontractors Ingersoll Machine Tool, Siemens, and MELD Manufacturing to manufacture the hull-scale machine, which uses metal additive manufacturing technology,” the announcement stated. The hull is the main, lower body of a tank.
MELD Manufacturing is a wholly owned subsidiary of Aeroprobe Corp., which in turn is privately held, MELD CEO Nanci Hardwick said. Aeroprobe was acquired by Schultz-Creehan Holdings in 2011. Aeroprobe and MELD are housed in the same building on Christiansburg’s Technology Drive. The MELD technology was developed by Aeroprobe and spun off into a separate company in 2018.
MELD is both the name of the company, and the specific 3D printing process. In a U.S. patent application found online, the inventors of the process are listed as Nanci Hardwick, Chase Cox, Jeffrey Patrick Schultz, and Kumar Kandasamy.
“The beginnings of 3D printing or additive manufacturing for metal began with very small components,” Hardwick said in an interview at the MELD facility. “And also those components could only be made out of special metals. Not just any metal could go into those machines or those processes. Often an existing metal had to be re-engineered to be successful in those machines and processes.”
Other processes typically use a heat source, such as a laser, to bond the layers together.
“The main difference between those and MELD is the ability to use any metal as it is, off the shelf, and to make very large components,” Hardwick said. “With MELD, we’ve figured out how to put just enough energy into the metal to make it printable without melting. By staying in a low temperature, the MELD process is able to do metals and parts that other processes are not.”
MELD printers rely on friction and pressure. The MELD friction tool and the source metal are rotated while applying downward pressure, creating heat which softens the metal and allows a layer to be deposited.
“Example would be, if you had a coathanger and start to bend it, it gets hot,” said MELD director of technology Chase D. Cox. “That’s what’s enabling the deposition. All the heat comes from deforming that metal. The friction starts the heat.
“The strength of MELD over laser is simply the material options and the size at which you can make a part. We’re at the cutting edge of what’s possible with MELD printing.”
MELD offers “the ability to print parts on demand, which means you can very quickly have a metal part, in any metal, replacing the normal existing supply chain,” Hardwick said. “Everyone reads about troubles with the supply chain. Additive manufacturing and the MELD technology alleviate those supply chain pressures by delivering the capability to print a part on site by the person who needs it.
“In the U.S. we’ve seen so much offshoring of large metal component manufacturing capabilities. For example, our region might remember that we used to have a foundry in Radford and we no longer do. There are many facilities that no longer exist in the U.S., and this has increased our dependence on foreign countries and foreign-to-domestic transportation routes for critical components.”
MELD specializes in large simple geometry parts, such as cylinders for fuel tanks, rockets, missiles, fuselages and submarines, rocket nozzles, parts for the oil, gas, and nuclear industries, and certain valves for shipbuilding which “are not a complex technology but currently only able to be sourced from foreign countries,” Hardwick said. “Those are fabricated with titanium which makes those very challenging to find elsewhere outside of MELD.”
MELD makes parts to order and also sells and leases machines to customers who want to make their own parts. It has contract to supply a machine to the Norfolk Naval Shipyard at end of 2022.
The Army contract started “started with a request from the Army that could be suitable for printing things like a tank,” Cox said. “Our pitch, Nanci and I delivered as part of a team with a few other businesses, and ultimately it was a unanimous decision by the Army for those large printers, at the heart to be the MELD technology, primarily for its ability to print any metal that they may in the future want to make a tank out of, including materials that don’t yet exist, and the ability for our technology to scale,” that is, make progressively larger parts.
So, what will this thing make? “That’s really at the discretion of those tasked with designing the next generation of tank vehicles,” Cox said. “The genesis of the program was the hull. Their focus was to improve ballistic performance,” meaning better armor. “When the vehicles roll over anti-tank [weapons] the vehicle survives and we don’t lose…those inside of it. That’s the genesis for this program, to make vehicles that are not susceptible to anti-tank type devices.”
“Monolithic hulls for combat vehicles have well-established advantages—especially in survivability and weight savings—but traditional manufacturing processes are not cost-effective or adaptable to full production, especially when multiple vehicle platforms are considered,” according to Army’s June 1 announcement. “While the ability to produce monolithic hulls is important, the new machine also will have the capacity to produce much larger additive manufacturing parts than currently possible.”
Under construction in Rockford, Ill., it will be installed at the Rock Island Arsenal, where foundation work is complete, according to Debralee Lutgen, a public affairs specialist at RIA-JMTC. Cox said he expected it to be operational by the beginning of 2023.
It’s clearly a new world for weapons designers, and also for MELD.
“We have a lot of opportunity in front of us, and we’re evaluating the best way to grow and serve the market,” Hardwick said. Options include soliciting investors, or going public.