The S-Max, the largest and fastest 3D sand printer currently available on the market, was introduced by ExOne in 2010. The S-Max works by selectively dispensing foundry-grade resin into thin layers of specially engineered sand. This additive process creates complex sand casting cores and molds directly from CAD data, eliminating the need for a physical pattern to create a core or mold. The ExOne S-Max printer is capable of producing prints up to the size of a phone box (maximum build volume 1800 x 1000 x 700 mm). And the process produces accurate, uniform cores and molds rapidly, significantly reducing lead time.
3Dealise uses the sand printing process to reproduce a damaged cylinder on a 1912 Brush car for a UK customer. The flexibility to modify and customize mold designs improves casting performance, reduces weight, and adds complexity to cast components. With this new S-Max 3D printer, they were able to finish the task in just two weeks.
The full-service concept offered by 3Dealise comprises scanning, engineering and printing. Without blueprints, they first started with 3D scanning the original cylinder. Using special software, they were able to correct the damage parts, add repairs and create partitions in moulds and cores. Next, they printed out the sand mould in multiple orders. When the printing process complete, the mould was cleaned, coated and then placed in a mould box. Casting was done the same way as the conventional process.
"This new technology is important for two reasons," explained Roland Stapper, CEO of 3Dealise.
"First, the success of UK manufacturing depends on the ability to quickly innovate and turn ideas into prototypes and then products. By enabling clients to go directly from a computer design to a high quality and high precision prototype, we can speed up the prototype cycle, which can give UK manufacturers a real edge.
"Second, there is a major trend away from mass production and towards customized products designed to meet specific needs. 3D printing is particularly well suited to produce customized products because every print can be different. Local UK production is crucial to this concept, because shipping time must be minimized."
3D printing of casting moulds is particularly well suited to create metal prototypes and small production series. The image below is sand prints for a Ø1200 mm pump created on the ExOne S-Max.
Sand prints for a Ø1200 mm pump
Watch a 3Dealise video below showing this capability being used to reproduce and repair the damaged cylinder on a 1912 Brush car.