Mahlkonig K30 grinding problems

Grinders are one of the keys to exceptional espresso. Discuss them here.
BTD1986
Posts: 146
Joined: 12 years ago

#1: Post by BTD1986 »

Hey everyone,

So I bought a Mahlkonig K30 brand new about four years ago and have used it for maybe 2 shots a day since. It has been flawless up to this point. Now, every now and then it will randomly start grinding much coarser for no reason. By this I mean, I will go to grind a shot and it will be perfect (aka dispense the grounds in the center of the portafilter, at the right dose and grind setting). Then I will do a quick purge flush then grind another shot. Then the resulting grind will be clearly more coarse, a significant increase in the amount of coffee will be dispensed, and it will come out of the grinder at a faster speed, causing a mess all over my counter, not centered in my basket like it normally is. When this happens, I will grind dose after dose and the same coarse grinding results, so that rules out stale grinds. The dispensed coffee is unusable for pulling a shot. Then even more perplexingly, the next day when I go to grind a shot, it will work perfectly, like nothing happened. I'm sorry if my description makes no sense or is confusing, but that is the best I can describe. I have tried adding more beans to see if the amount of beans in the hopper is the problem but that hasn't solved anything, the grinder will grind much coarser in random intervals, but then grind perfectly fine for several weeks before causing problems again. So that leads me to think that it can't be the burrs either. I have used this grinder regularly enough that I know it is behaving irregularly, but I can't figure out what it is. Any help would be greatly appreciated, sorry if I dragged on too long but I know this forum appreciates details.

Cheers!

Advertisement
thepilgrimsdream
Posts: 310
Joined: 9 years ago

#2: Post by thepilgrimsdream »

I notice some more inconsistency with my K30 and Peak ever since I moved them next to the window in my kitchen. When it is warm, I need to grind fine, when it is cold, I grind coarse. I actually monitor the temperature and humidity to dictate my grind. Also, they are inconsistent with less than 2lbs of beans in the hopper.

https://www.amazon.com/AcuRite-00613-In ... 0013BKDO8/

Just some of my personal experience.

Also, there may be a misaligned or loose burr or something funky going in there. I would take a peek inside when you get a chance.

Good luck!

Beaniac
Posts: 179
Joined: 9 years ago

#3: Post by Beaniac »

Are the calibration screws still tightened well? They are two hex screws under a plastic ring on top of the grinder where the throat of the bean hopper locks in.

If these screws slip, the grind will move a step coarser under rotation, adjusting the grinder might cause them to move around as well if they are not tight.

BTD1986 (original poster)
Posts: 146
Joined: 12 years ago

#4: Post by BTD1986 (original poster) »

Thanks for the suggestions, I'll look into them. I've been using my backup grinder recently so I don't waste anymore coffee.

Yoyota
Posts: 1
Joined: 7 years ago

#5: Post by Yoyota »

I had a problem with the k30 burr ring loosening up because of the vibrations. I solved it with a small piece of plumbers teflon tape on the threads. Too much tape and it is hard to turn. Hope this helps.