1Zpresso K-Max grind setting and burr seasoning

Grinders are one of the keys to exceptional espresso. Discuss them here.

#1: Post by wormraper »

I haven't had a new grinder set for a long time, but I picked up the 1Zpresso K-max series the other day. been dialing it in all weekend. The first few cups were definitely over extracted as I figured out where the default grind setting should be at.... however, after the first 8 or so 20 gram grinds I noticed that it felt weaker. Like I wasn't extracting as much even though I was grinding at the same setting that I had the day before as the pre-determined "sweet spot"... end result, I had to grind 4 clicks finer on the grinder to get the flavor that I had 4 clicks coarser....

my question is.. is this just expected as the burrs season for the first pound or so as they "settle" or is this not normal ??

(I have about 10-12 twenty gram "cups" through the grinder. I haven't had to use a brand new grinder for 7 years so I can't remember if I did this with my encore or not. Just found it slightly weird to have the perfect cup on click 9.2...only over the course of today find it too weak and have to dial it down cup by cup to settle on 8.8 for my french press....I'm now a little over caffeinated at 4 cups today "testing" to get back to that perfect taste)

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#2: Post by redbone »

Also have a J-Max which I use only for espresso. Although 1zpresso claims the J-Max to be an all around grinder it's divinely geared towards espresso considering the small incremental settings and burr set. Took me a while to find the sweet spot for my current setup LP Europiccola but once dialed in I have not needed to change the setting. Different flavour profile than my Major E (conical vs flat) but it's been very consistent even with varying coffees. Fun addition giving me neuromusculoskeletal feedback that one doesn't get from an electrical grinder.

Between order and chaos there is espresso.
Semper discens.

LMWDP #549

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#3: Post by Pressino »

It could be your coffee is just aging (involves loss of aromatic compounds and chemical change in the bean--i.e. getting stale). This can change the grind setting you have to use and can happen over a short period of time (a day or two might be enough) to require a change in grind setting...usually a bit finer. Or it could be, since your grinder is new, that the burrs are slowly wearing in or it just needs careful cleaning and reassembly (easy enough on the 1-Zpresso grinders). If you use dark oily beans that would require for frequent cleaning. The built up gunk can change the grind quality over time.


#4: Post by mikelipino »

Hi Mike, I went through the same dance around April with the JX-Pro. Looking through my notes, it took about 1.5 kg beans, or about a month, before the grind settings weren't all over the place. Luckily the coffee is definitely drinkable as you season (and increasingly, it'll be pretty dang good). And drip will be much more forgiving than espresso during the seasoning process. But one day the grinder will seem to "click" and settings will seem to lock. Keep at it, and let us know when you start getting some good cups!
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wormraper (original poster)

#5: Post by wormraper (original poster) replying to mikelipino »

sounds good. I just wanted to make sure what I was experiencing was normal being that this was my first NICE hand grinder. It's not like it was stupid crazy, just 4 clicks finer than what I did the other day, but I also haven't put even a half lb through it yet.

I've been using super super light Guatemalan beans from S&W too, so it's not too gunky on the blades... figured it was just the blades wearing in a bit, but wanted to be sure

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#6: Post by JB90068 »

Not sure how much different seasoning a hand grinder is vs. an electric grinder, but I've found with all my electric grinders that I needed to go through several pounds of beans to consistently pull the flavors I was looking for. With my newest grinder, I ran 10 lbs through it in two days before I got shots I was looking for. Doing that much by hand and you won't have to go to the gym for a while. :D
Old baristas never die. They just become over extracted.


#7: Post by mbbrew »

My K-Plus definitely needed seasoning. My first week or two of grinding I was getting a lot of fines and then it started to improve. After a few months of use I was using a significantly finer grind size setting as the prior settings as the draw down speed started to increase and I was getting weaker cups. I put about 50g through it daily and have had it since March and it seems to have leveled off a few months ago.

wormraper (original poster)

#8: Post by wormraper (original poster) »

Sounds good. After about a dozen more brines it started to settle.

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#9: Post by r-gordon-7 »

I just received a J-Max earlier this week and I haven't ("yet"?) noticed any shift in the grind setting so far. Though, it would probably be to soon to notice anyhow, as after only four or five 16gm pucks/32gm shots (all of which were quite drinkable, BTW), I'm still at the early stages of "fine tuning" the dialing-in of the grind, given how many clicks there are within espresso range on the J-Max!.

However, I did immediately, right out of the box, notice something that had me a bit concerned with mine. When initially turning the Adjustment Dial Ring to "zero-it in" to the "starting point" - that is, to have the Adjustment Dial Ring's engraved "zero click" point exactly match up to the Scale Mark on the side of the J-Max, there was only the very slightest hint of any "catch" in the burr mechanism with the Adjustment Dial Ring's engraved "zero click" point set to exactly match the Scale Mark. And this hint of a catch only occurred at one brief point in the first rotation of the crank at that click point, and then instantly disappeared as the crank continued to turn without any further hint of catching at all. I actually had to continue on moving the Adjustment Dial Ring down ("finer") to about 6 or 7 more clicks below that Zero "starting point" click before I got to a "click" that could be considered the first click where the burrs could really be said to begin to "catch".

I do see the following in the J-Max User Manual's section that desccribes "Assembly and Calibration" (for use after "Disassembly" for cleaning), "Note the starting point might be different within +/- 10 clicks due to the strength you tighten the nut and dial." So, would it be correct to assume that the "starting point", right out of the box, being off by 6 or 7 clicks "finer" than the Adjustment Dial Ring's engraved "zero click" point against the Scale Mark, would still be within normal tolernces? And is it possible that "burr seasoning" might eventually bring the "actual" starting point back up, closer to the Adjustment Dial Ring's engraved "zero click" point"? Or, might "burr seasoning" actually work the opposite way, and move the "actual" starting point even further down (i.e. even more clicks "finer") than the Adjustment Dial Ring's engraved "zero click" point? Or - am I just obsessing over nothing more than normal variences within accepted tolerances for the J-Max? (Which other than for this one issue that may really be nothing, I really, really do like so far!)
LMWDP #188


#10: Post by Jonk »

Don't worry - it will likely improve after the burr is seasoned (after several kg). The starting point or at least initial rub should move down. Even if it doesn't, that doesn't seem like great alignment but acceptable in the sense that it shouldn't stop you from brewing great espresso.