What business wouldn’t want to increase quality while streamlining processes and reducing final costs? This is what Bastech achieved in a remarkable benchmark test it conducted to compare conventional baffle cooling to conformal cooling mould making methods using 3D Systems’ end-to-end digital manufacturing workflow. As a 3D Systems partner, the Ohio-based additive manufacturing services and equipment provider has over two decades of experience using additive manufacturing to solve a wide range of applications, from functional prototypes for the automotive industry to complex investment casting patterns for end-use aerospace components. Already aware of the potential benefits 3D Systems’ workflow stood to offer, Bastech was nevertheless blown away by the actual results they achieved.
Bastech found that using 3D Systems Cimatron mould-making software, the ProX DMP 200 3D printer, and Geomagic Control inspection software led to a quantifiably more productive, affordable and streamlined manufacturing process over conventional methods. The company reduced design time by a staggering 70%, shrank cycle time by 14% and cut overall costs by 16%. In the manufacturing industry where success is a delicate balance of efficiency, cost and quality, Bastech had landed on a clear competitive advantage.
Since the inception of industrial injection moulding, maintaining an even temperature on the surface of the mould has been a constant challenge. Over the last decade or so, conformal cooling, or cooling channels designed to naturally follow the contours of the final production part, has been identified as a viable solution for controlling injection-moulding temperatures. Apart from design complexity, the greatest hurdle to implementing conformal cooling has been the challenge of transforming the moulds from a concept into a viable part. These difficulties have put the conformal cooling beyond the means of most shops, but Bastech’s success may introduce a shift in manufacturing approach and capability.
Bastech conducted two benchmark tests to compare conventional manufacturing techniques with 3D Systems’ end-to-end workflow. The first benchmark was of a tapered helix on the inside of a spacing cone for industrial assemblies; the second was a complete core, cavity and slide-mould set. For each test, Bastech created its conformal cooling design with Cimatron, an expert CAD/CAM software by 3D Systems that covers the entire mould-making cycle, from quoting and design to applying engineering changes and NC and EDM programing. Cimatron also includes design and analysis tools for both traditionally manufactured and 3D printed cooling channels. Cimatron even offers automated mould-filling analysis to optimise cooling channel layout.
“Designing for 3D printing requires an understanding of structural support design to accomplish true requirement-based design as well as reducing material cost and build time,” says Scott Young, Bastech’s Engineering Manager. “This type of expertise is built within Cimatron software to allow our designers to think about design without having to worry about navigating through the CAD package to define complex internal channels.” This integrated expertise was crucial in accelerating design time and moving from file to print without exhaustive delays and tedious reworking.
For the first benchmark test, Bastech used Cimatron to create conformal cooling channels in a rotating teardrop configuration that ran at a consistent parallel to the outer surface of the core. The final file was 3D printed in a single run in maraging steel on the ProX DMP 200 and compared to a traditionally manufactured baffled core.
“The ProX DMP 200 enhances our moulding capabilities and gives us higher turnaround tooling and solves bottleneck problems in the shop,” says Ben Staub, President and Owner, Bastech. “We can save 30-40 hours per mould by eliminating EDM and drilling, and drastically reducing CNC and polishing work.”
Complex conformal cooling channels created with the comprehensive mould design toolsets of Cimatron led to a 14% reduction in cycle time and 16% reduction in overall costs.
In this first benchmark test, Cimatron and the ProX DMP 200 saved more than 40 hours of programming and shop time, and yielded a net savings of 18% over conventional methods according to Bastech’s engineering manager. Bastech then used Geomagic Control for digital part inspection to ensure that the final part quality met its expectations. The benefits of the 3D Systems workflow were proven to be even greater once the mould was put to work, where it reduced cycle time by 22%.
"Cycle time is nearly everything in injection moulding,” says Staub, “with the ability to consistently control temperature a close second."
It follows that for Bastech’s second benchmark test, the goal was to maintain the same temperature between the conventional and conformal designs to see how the two techniques would affect cooling and cycle time results. Once again, automation within Cimatron software reduced design time from 30 hours to just seven, with a total cost savings of 16% for the 3D printed conformal cooling mould. More importantly, cycle time shrank again, down 14% as compared to traditional methods. Again, use of Geomagic Control inspection software guaranteed final part quality.
“Even though the temperature remained the same for both the conventional and the conformal cooling designs, the conformal design forced more liquid through a greater surface area, making it more efficient in cooling the mould,” says Young.
"With traditional cooling for injection moulding there is no perfect situation," says Staub. "You can only drill holes in certain places and you can't curve holes around channels like you can with conformal cooling designed for 3D printing. Now we no longer have to accept compromises in conformal cooling designs."
After rigorous testing, Bastech proved the value of 3D Systems’ robust digital manufacturing solutions to help its mould-makers make better decisions faster and bring them into reality with direct metal 3D printing.
"3D Systems' end-to-end solutions take our business to the next level by saving our designers and engineers time and energy in developing and executing complex designs,” said Staub. "The bottom line is that by working with Cimatron, Direct Metal Printing and Geomagic Control, we are designing faster and making more efficient moulds more economically.”
