mike01 wrote:The only way I can get a fine enough grind is to have the grinder calibrated with the zero point (burrs touching) at a higher setting and then grind below this point to get a fine enough grind.
It sounds like you have one of those "faulty" K30s.
Around 2014, there was a batch of K30s that had a problematic grinding chamber. I know it because I was "lucky" enough to get one of those grinders.
No matter what I did, I could not grind fine enough. Since I was a "rookie" back then, my solution was to only pull 23g of coffee. That was the only amount for which I could get a decent flow rate, when grinding at near 0 (0 - touching burrs).
By the time I realized something was wrong with my grinder, it was no longer covered by warranty.
Luckily enough, the guy @ Mahlkonig USA gave me a discount on a new grinding chamber. I do not remember exactly, but it was ~$150.
After installing the new grinding chamber - all problems were gone. I rarely use my K30 these days, but when dosing 18g, the settings are at around 3 - and I get the right flow.
I may be selling mine, but I haven't decided yet