1Zpresso K-Plus Calibration Drift?

[mbbrew]

I've had my K-Plus for almost a year and up until the past few weeks it has been my go to grinder, even beyond my flat burr options for filter some days. I was typically grinding in the mid 6 range for filter coffee after seasoning, where I was in the low 7 range. Suddenly I was getting crazy long brews at this range, and even at 7-7.5 I'm getting much longer brews than I was at 6.5, with a visibly muddy cup. I pulled the burrs to visually inspect them and I can't see any damage. My burr locking point is still at 0. If I back it off to around 0.5-0.7 and spin the burrs, I get touching that isn't perfectly even, but doesn't seem crazy out of alignment. Has anyone else had something similar happen? I transport my grinder back and forth to work every day but it is usually in its case, but it has been knocked around a few times. When I was still using an Encore I had something similar happen, but the plastic burr carrier had broken, while in this there is really nothing to break. Could I have slightly bent the shaft and caused misalignment?

[Coffiend]

I have the K-Max which should be mechanically identical. With my burrs locked at 0.0, they will continue to contact one another until 0.5, where they will move completely freely (albeit with some visible burr wobble). So it doesn't sound like there's anything unusual about yours.

My first thoughts would be; did this change coincide with a change in coffee? High grown/high density beans can produce more fines, causing a longer brew time. My other thought is kettle temp/calibration? If using a temp controlled kettle, it may be faulty/registering a higher temp, and therefore a lower brew temp will brew slower with more visible fines. Lastly, technique can play a part too. Excessive agitation causing fines-migration throughout the brew.

Oh and I suppose a change in municipal water chemistry can play a factor! (Unless you make your own brew water).

[mbbrew (original poster)]

I make my own water, have multiple kettles, along with having tried these coffees on other grinders where I am not experiencing this, and have six different coffees open right now, along with some frozen ones to compare. I've even validated temperatures with a thermometer. That is why I am at a loss. I've also got a Tricolate, and a Hario Drip Assist, the latter of which I would typically get very clean looking beds of coffee after using, which is no longer the case. The only thing I haven't done is sieving tests, although it would be nice to have the original data points to look back on.

[_Ryan_]

Contact 1zpresso, they're pretty responsive. info@1zpresso.com