What companies like Markforged, Desktop Metal and Admatec reintroduced to the world of manufacturing was the idea that 3D printing is already capable of producing metal parts through indirect methods. Whereas these companies are capable of producing metal-infused polymers that are then sintered to create final parts, investment casting, particularly in the jewelry and dental industries, has relied heavily on 3D printing.

3D Hubs has just added its own version of metal 3D printing via investment casting to its broad network of 3D printing services. Unlike companies like Shapeways, Sculpteo and Materialise, which use stereolithography and digital light processing to produce objects for casting, 3D Hubs is using fused deposition modeling (FDM). This makes 3D Hubs the first company to offer castable plastic 3D printed via FDM.

A metal part alongside the 3D-printed patterns required to created it via investment casting. (Image courtesy of 3D Hubs.)

Though 3D Hubs also offers direct metal 3D printing processes, service providers in the 3D Hubs network will make it possible to cast metal parts five times cheaper than other methods by producing FDM parts using PolyCast, a castable filament designed by Polymaker to have a very low burnout (necessary to reduce deformations in the metal part).

Metal parts made by this method begin as a pattern 3D printed in PolyCast on an FDM machine by a hub. The pattern is then polished using Polymaker’s unique Polysher system, which smooths objects using isopropanol and prevents air bubbles from being trapped on the surface of the ceramic mold that will be used to cast the parts. Once polished, the pattern is sent to a foundry for casting. Parts with critical tolerances are further machined to specification and sent to the customer.

A price comparison of stainless-steel parts with varying geometries 150mm x 130mm x 55mm in size. (Image courtesy of 3D Hubs.)

In addition to the price, FDM can also produce large complex patterns that would be difficult to make with traditional manufacturing. 3D Hubs points out that “if a design is approaching the size of a basketball, FDM-printed patterns become the most cost-effective method for producing custom metal parts with complex geometries.”

The service will be available starting on three continents. Users can upload a file here to get a free quote.