In this month's issue of Mold Making Monthly, we asked whether 3D printed core and cavity inserts are ready for prime time. Well, it seems that Diversified Plastics Inc. believes they are. The employee-owned custom injection molding company that provides a range of services including moldmaking, just purchased its first 3D printer, a Stratasys Objet260 Connex 3D printer.
Annette Lund, VP of Diversified, told PlasticsToday that the company purchased the Objet260 primarily for creating cores and cavities for prototype molds. However, the company will also use the new printer to produce prototype parts that simulate diverse mechanical and physical properties.
Prior to purchasing the 3D printer, Diversified sub-contracted its' additive manufacturing prototype projects to local service bureaus. The SLA and FDM parts were primarily prototypes for customers who needed them for product development purposes.
"We're taking rapid prototyping to the next level with the addition of the Objet260," Lund said. "This machine offers us a lot of versatility with respect to materials. So far, in the month we've had the machine, we've done parts in a TPE (Santoprene), ABS, 30% GF Nylon, and polycarbonate in four trials, and all the materials worked really well."
Building cores and cavities that can actually be inserted into a mold base requires some additional work such as flattening out the top surface to the halves fit together tightly under molding conditions. The materials for the cores and cavities can typically produce up to 20 parts in the trials that Diversified has conducted so far, depending on the materials and the complexity of the part, Lund said.
Diversified also adds water lines to improve the molding conditions, even though Stratasys said it wasn't necessary. "We found the mold works better and the parts come out better if we put water lines in," Lund said, adding that so far, the cores and cavities they've built using the Objet260 have taken about 12 hours to build, and another day or so in the mold shop.
"I think three days total is the fastest we can get a prototype mold and molded parts for customers," she said. "And when we've asked our customers to compare the parts we've had built at a service bureau using the FDM process with the parts we've molded in 3D printed cores and cavities, the customers actually liked the molded parts better. The surface finish on the molded parts was much better than the FDM parts."
Lund believes that 3D printed core and cavity inserts will offer Diversified's customers more options with respect to product development. "We have been showing this technology to our customers and they're really excited about it. It's the wave of the future."
Diversified currently operated 18 presses ranging from 50-610 tons clamping force, and serves customers in the medical device, filtration, aerospace as well as a variety of other industrial markets. The company is ISO 9001:2008 and 13485:2003 certified, ITAR certified and UL registered.