I recently cleaned my Maestro plus, something that until recently, happened once a month. After cleaning the burrs and grinder I realized that the ground coffee I was getting was at a completely different size than what I was used to on that setting.
I use the "20" setting on my Maestro because some grind charts that were published online showed that setting had the highest uniformity in particle size distribution. Knowing that my grinder is not perfect (and that I don't have access to a roller mill) I decide to keep that setting constant and play with other variables. This seems to work given I mostly brew some style of filter coffee.
However, unless my grinder is cleaned after every grind, I now know that every time I grind coffee it will have a different particle distribution even at the same setting. I feel stumped, I am wondering if the charts posted online ( on the Marco Uber site) are from grinds coming from clean or seasoned grinder? The best answer Ive gotten was that for those charts to be valid they would have had to come from clean grinders as this was the only way to keep the experimentation constant. However, no one (or at least no one I know) cleans their grinder after every grind. It seems to me then that these initial plottings should come supplemented with charts of particle distributions on grinds that have happened after certain amounts of coffee have passed through the burrs. Thoughts, comments, opinions are greatly appreciated.