An apparently logical combination of production technologies made a high-profile debut at IMTS recently: GF AgieCharmilles and its partner EOS demonstrated what they called “a nearly automatic process chain” for producing injection and blow mold tooling with conformal cooling channels.
Their “breakthrough” process chain could be set up to run as a virtually sequence, from design to finished product. The machines used in the process — GFAC’s electric-discharge machining systems and EOS’ direct metal laser sintering system — are networked to operate from the same 3D CAD model data, from start-to-finish. The union of machines reportedly increases data accuracy and reduces set-up times.
“Our technologies are a perfect fit for moldmaking,” stated GF AgieCharmilles U.S. business development manager Gisbert Ledvon, “and the transfer between our systems is unique.”
GF AgieCharmilles develops and supplies laser ablation centers, wire EDM, CNC and manual diesinking systems and high speed/performance, and 5-axis CNC milling machines.
EOS manufactures laser-sintering systems, which have emerged as a primary technology in “e-manufacturing” of consumer and industrial products, patterns, and tools.
During the demonstration at IMTS, an EOSINT M 270 direct metal laser-sintering (DMLS) system was shown creating a steel mold for a plastic, blow-molded golf ball, complete with conformal cooling channels and the fixturing needed for all successive stages of machining.
Then, the mold moved through a secondary process chain that included a GF AgieCharmilles HSM 400U LP high-speed milling machine; an FO 350MS die-sinking EDM; and a Cut20P wire EDM. The wire EDM cut off the fixturing, and the HSM 400ULP cut the parting lines for a flash-free (no leakage) surface, leaving the mold ready for production use.
A significant advantage of DMLS is that it produces a near-net part, in one operation, that is ready for secondary finishing. Then, single-fixturing is used for all secondary operations to reduce manual benchworking and generate surface finishes accurate to within three to five microns. The process minimizes scrap by eliminating many of the progressive operations involved in subtractive toolmaking processes that start with a block of raw material.
“By joining with EOS, we have established a complete process chain, available globally, that provides the same high accuracy GF AgieCharmilles is known for, and creates tools with a minimum of oversight and greatly reduced material waste, manufacturing time, and manual labor,” Ledvon said. “It’s better for the environment, and it’s excellent for the bottom line. The conformal-cooled molds we can manufacture offer enormous advantages.”
Conformal-cooled molds have already been used in commercial production, and allow some high-end manufacturers to reduce part-production cycle times by 17-20% — in some cases as much as 45%. DMLS-manufactured molds improve product quality and promote longer tool life, and the optimized cooling increases the efficiency of the whole molding process as well.
For large-volume production, the time and cost savings that result are considerable, as might be the reduction in an operation’s carbon footprint.
“We’ve documented years of success stories from customers who benefited by using DMLS to create molds that employ conformal cooling channels,” stated EOS North America’s regional sales director Andy Snow.