How do you make curta calculator?

To make a curta calculator, you'll need to source the necessary mechanical components, such as gears, levers, and a cylindrical casing. Begin by designing the internal mechanism using a series of interconnected gears that can perform basic arithmetic operations. Assemble the parts meticulously, ensuring they fit together smoothly for accurate calculations. Finally, calibrate the device and test its functionality for precision in operations like addition, subtraction, multiplication, and division.