I feel there is very little calculation going on in the design. To be useful like pascaline you'd need at least some convenient way to input numbers.

Maybe have a look at the Curta for inspiration of a mechanical calculator. There's a 3D printable version of it.

https://www.youtube.com/watch?v=j9uRckJLqLk https://wudev.digitaltorque.com/articles/curta-1/

Reminds me of the purely mechanical computer Z1 with 16-word floating point memory, Keyboard and punch card reader: https://en.wikipedia.org/wiki/Z1_(computer)

Would be interesting to reconstruct that using a 3D printer... if anyone has too mich time to spare.

There are probably designs that are more print-friendly than gears (rod logic?). I wonder how far you could go with just a 3D printer if you really optimize for the efficiency.