Injection Molding & 3D Printing Combine to Make ‘Impossible’ Parts
Stereolithography cavity inserts can be injected with thermoplastic, then removed from the mold and dissolved away to leave a complex-shaped part.
3D printed cavity inserts (left); inserts injected with thermoplastic (center); and thermoplastic parts after the cavity insert is dissolved away.
Share
Could this be the ultimate crossover between injection molding and 3D printing? At next month’s Rapid + TCT show and conference in Detroit, AddiFab of Denmark (addifab.com), Mitsubishi Chemical America, and Alba Enterprises will collaborate to provide an answer. AddiFab (U.S. office in Palo Alto, Calif.) supplies 3D printing machines and materials that use a stereolithography technique to light-cure liquid resins. Its Freeform Injection Molding (FIM) process (freeforminjectionmolding.com) involves building a cavity insert in the form of a short cylinder with a hollow cavity inside and a sprue hole at one end. This insert is subsequently rinsed to remove all uncured resin from the cavity inside, and then is post-cured to develop full properties, including high heat resistance (high enough to permit molding PEEK). At the Mitsubishi booth (2105) at the show, the insert will be placed in a mold base in a Babyplast tabletop injection machine (sold in the U.S. by Alba) and injected with Mitsubishi’s high-performance TPE. Then the insert will be removed from the mold and dissolved in an alkaline water solution, leaving a thermoplastic part whose complex shape would be “impossible” to injection mold by conventional methods.
RELATED CONTENT
-
Tooling Know-How: Five Tips on Profile Die Design
A poorly designed profile die—one that does not permit the part to be extruded with the same dimensions from run to run—coupled with a lack of understanding of the extrusion process, is a recipe for scrap generation.
-
Know Your Mold Coatings
Nowadays, there's a lot more to mold wear and corrosion protection than just hard chrome and electroless nickel. Some tools need more protection or more lubricity than they can offer. Here's one expert's guide to the newer options.
-
INJECTION MOLDING: Setting Mold Protection Takes Time But Saves More
Mold protection is often neglected, but it more than pays for the time and attention required.
