Sometimes I think that espresso is akin to the slogan for the game Reversi(?): A minute to learn; a lifetime to master.

Some follow-up and observations from my experience so far.

To summarize:
Used K30ES DC13802 / SC 5024. (older grind chamber)
Using Metropolis Redline 21 g triple with a bottomless PF using Duetto2
5.3s grind time. Grinding on setting of 1.0
Mild clump balls, that break rather easily.
No WDT. Stockfelths and a Bumper convex tamper. No nutating, just straight down.
Good drinkable but not great shots.

Burrs replaced with a new Mahlkonig burr set ($135).
Grind time shortens to 4.0s. Grinding now on a lower setting of 0.5 when burrs are zeroed on setting of zero.
A bit more clumping (still not as terrible as others have described) , but definitely more counter mess.
Inconsistent shots. Drinkable, but relatively thinner.

My thoughts:
1) Seasoning of new burrs? I ground 3 pounds of stale beans and a couple of rounds of Grindz. Not much change.
2) Trueness of the burrs. This is the only conclusion I could come to. This makes the most sense to me. I rechecked the burr orientation and seating. I made sure the upper burr carrier had clean threads that traveled smoothly. No change.

I had thought about getting the new grind chamber upgrade for Christmas since I had already surpassed my grinder budget with the new burr set. The people who posted about the grind chamber upgrade seem to be really happy with the results. There are a few videos out there in internet land demonstrating this.


Decreased grind time, decreased setting, inconsistent shots still seemed like a burr trueness issue to me. When I zeroed the burrs, I felt there was a slight high spot, kind of like when you fine tune a road bicycle wheel. I talked to Brian @ Mahlkonig USA. He said the most common cause for this in his experience is improperly cleaning the burrs and carriers of coffee residue prior to seating the burr set. I knew this was not the cause in my case, because I was watching out for this. I asked if the new chamber upgrade included a new upper burr carrier and threading. He said yes, so I decided to pull the trigger a little earlier.

The new grind chamber upgrade ($125) arrived Friday. Nice machining. Easy fit. Just need to use your burrs and the lower burr carrier.

All problems are now fixed.

Now grind time is still 4.0s, but at a setting of 2.5 when burrs are zeroed at setting zero. Super fluffy grinds directly into my PF basket. Virtually no clumps, and absolutely no counter mess! Amazingly even extraction visible with the bottomless PF like I have never experienced before. Incredible improvement in depth and taste of my coffee. Consistent too!

Now i am only curious what the three unused threaded holes in the brass ring are for?

Great to read yours is working for you now!

This is an interesting topic as i have just purchased a new K30 vario and have noticed on all pictures and videos the grind settings for espresso were sort of between zero and two whereas mine came set and no doubt tested at 4.5 and even at that setting i am thinking that the grind is a bit too fine i am slowly messing about with the settings timings etc but i think i will need to adjust the grind probably up to 5.5 or even 6
I would agree that this machine is very clean no grinds whatsoever going on to the counter and nothing more than a couple of specks on the bottom tray

As for grind retention i am not bothering to purge any at the moment as i am still trying to dial it in, but i would say that the grind retention is very low as we cannot yet notice any taste difference between the first second or even third or fourth shot even after a 24 hour break between use
I cant wait until we find the correct settings and timings for this machine

Since the burr and chamber upgrade, I have just been so happy with this grinder. It is so nice, quiet, quick, easy, and no fuss. I have sampled many different blends since I have owned it. Since the upgrade, I find I am using settings between 2.5-4.0 for espresso (3.5 for RedBird). Again, the settings are all relative based on the zero setting, but I think there was a problem with my burr carrier trueness on my used machine when I bought it that was resolved with my chamber upgrade.

There is no reason not to go with the Vario version IMO, but mine was an ES (stepped) and I did not have the option. I feel the steps are plenty small for my needs, and feel no need to upgrade this (or mod).

I hope you enjoy using your grinder as much as I am enjoying mine. Cheers.