We recently had the privilege of delivering and installing another fully enclosed Atlas 2.0 to a foundry in Minnesota, Alliant Castings. It’s a wonderful, family owned business that’s been around for decades and they’re looking to shake things up and by working with 3D printing to improve upon traditional foundry processes.
Alliant Castings estimates 3D printing will save half the cost and is three times faster than traditional pattern making processes.
We first met owner Tom Renk earlier this year at American Foundry Society’s 2016 Cast Expo. It was an incredible opportunity to see how large-format 3D printing could help this long standing industry of metal casting. Tom and his brother, Marty Renk, said they had been looking for new ways to lower costs and lead times and believed 3D printing was the answer.
It wasn’t long after that Titan Robotics printed out sample parts for Alliant Castings to test in the foundry. We 3D printed two parts out of ABS on our large-format 3D printer the Atlas, called the cope and drag. (Cope and drag refers to the top and bottom parts of a mold in sand casting).
The ABS prints took about 12 hours each and once complete Titan Robotics shipped the two pieces off to Alliant Castings. Within 24 hours of receiving the 3D printed sample parts they had mounted the parts, molded them and poured metal into them. Below you can see the mounted ABS pattern and the final metal product.
Alliant Castings is now using an Atlas 2.0 with a heated enclosure in their pattern shop, instead of outsourcing the work to a pattern maker that creates the pattern by hand or with a CNC router. This saves Alliant an immense amount of time and money. Tom and Marty said this job would have likely taken two weeks to get done without any delays or backups, and cost them about $3,500. Instead, with 3D printing it took 24 hours and cost a total of $1,300 (including payment to Titan, engineering and labor time).
Tom and Marty said they’ll be able to use 3D printing for low volume and one off jobs, as well as mass production jobs.
Because ABS is a strong and high temperature plastic, they’ll be able to use ABS printed parts in pressure molding or squeeze molding. This process, also called greensand casting, is fast and automated, making 120 molds an hour out of sand. It is also a high density and high pressure method, which is why ABS or other high-impact rated plastics must be used.
When it comes to smaller jobs that don’t require as many molds, Alliant will be able to print out of PLA for the no-bake (air set) method of molding. This method tends to have higher accuracy and surface finish compared to greensand casting.
But Tom and Marty see other uses for 3D printing at Alliant Castings, including printing master patterns that can be used for one-off parts or mass production. They also plan to experiment with burning out PLA when pouring molten metal, similar to lost-foam casting. If this method proves successful, it would open up a new and different market for one off parts that are unique or difficult to mold.
Like any industry, the need to become more efficient and cost effective for their customers is driving innovation in foundry. Alliant Castings is sharing their knowledge with others, and say other foundries have even approached them about 3D printing patterns for their shops. Alliant has seen such an improvement that they are already investigating purchasing another 3D printer to increase their speed and capacity to make patterns quickly.
And with Titan Robotics large-format 3D printers in a fully heated enclosure, Alliant is able to design and print full size patterns out of the materials they need, such as ABS or polycarbonate blends, as well as PLA. We look forward to seeing what Alliant is able to accomplish and the new processes they discover using the Atlas 2.0!