Maybe you are under the impression that affordable 3D printers can only be used to produce cheap little plastic parts. Maybe you should think again. 3D printers can easily create shapes for investment castings. The plastic is coated with a ceramic material. After multiple layers are applied, the plastic is burned out in an oven leaving a void that can be filled with metal. The ceramic makes a good finish and the technique can be used with steel, aluminum, stainless steel and many more materials.
Investment casting at PPCP
There is even a special filament called PolyCast. It’s easy to print with the same settings as PLA. What makes it special is the limited ash left behind when it is burned out of the ceramic shell. YouTube Video: https://www.youtube.com/watch?v=4–fiBGMIpc
In my own experience: Several years ago, I reversed engineered a brass impeller that provided lube oil to a large generator-turbine unit in a power plant. The pump was printed and sent to Pennsylvania Precision Cast Parts. They added the venting and gating to the part, and the cast the part in stainless steel. It was a complicated shaped that can be done lost wax, but 3D printing made the job easier and much cheaper. After casting, the outside diameter and boring were machined ,and a keyway was added. The impeller was balanced and there were a few other trade secrets added.
The process saved time and money and the impeller has been running without issues for over a decade.
Remember this then next time someone asks, so what can you make with your 3D printer.
Polycast is available at Amazon
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