200-300g fluctuation is not a nominal performance, but not catastrophic enough to be explained by a big issue.
Batteries health doesn't explain the fluctuation.
What is the most likely is a small friction somewhere in the mechanical system. Of course by triggering 3 times the measurement and keep the median would work, but it's clearly sub-optimal, and will reduce significantly battery life.
I'll discuss with Juan what we can do, but I think about two things :
- A video to explain where to look after mechanical friction, some tips, and how to evaluate by hand the sensitivity.
- A software procedure to run x times the balance search, and quantify the dispersion. With that we would have a factual value, and give some reference value.
To make it short, you may have a small burr on the tips of the knives (which are laser cut inox, so blurr is unavoidable, but you can remove it during assembly), and you may have some misalignment during assembly, that make two parts touching while it shouldn't. Difficult to explain without a sketch.