Your Grinder has Narrow Sweet Spots Too, Right?

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

#1: Post by coffee.me »

I really, REALLY, hope your answer to the subject line will be: "Yes, everybody does, duh!". Otherwise, I'll have to work on my technique or my grinders; and I'd rather not!

I'll be brief in the hope your answer will be positive. On a couple of my grinders, the following applies to different coffees(artisan blends, SO home roasts, fresh dark&oily ash), machines(58mm commercial HX, 43mm-ish lever) and different pressures & temps, I noticed the following narrow sweet spots:

My Super Jolly for VacPot
Around a certain spot, I get a medium-coarse grind with the least amount of fines and the resulting pots are far superior to when going a bit finer or coarser.

My Versalab for espresso
Amazing shots happen around the 20g mark and the 12g mark. Between 14-18g, it almost always brings the worst in coffee and masks the best.

For all I know(and hope!), this is something everybody is well aware of and I just missed it somehow.....please say yes!

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cafeIKE

#2: Post by cafeIKE »

IMO, there is an espresso no-mans-land between fine & low and coarse & high. The better the grinder, the narrower the region and less dramatic the edges.

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another_jim
Team HB

#3: Post by another_jim »

Sorry. C_O_N_I_C_A_L.

The burrs move past each other, not towards each other, when you adjust the grind, so the sweet spots are huge
Jim Schulman

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coffee.me

#4: Post by coffee.me »

So far I'm getting "yes, grinders have sweet spots". I know that's what I hoped to hear; but it also is a confirmation that my Versalab's 15g doubles will never be amazing -- sad, really.

But how come nobody says: "my grinder doesn't do 18g well", and instead they say: "my machine doesn't like to be updosed"? I dunno, this confirmation opens the door for so many questions* that I'm starting to think we're not talking about the same thing. Really? Narrow sweet spots? :shock:





*e.g.

- Why isn't this commonly discussed? I never came across such a discussion, I even searched!
- Does the "location" of such sweet spots change when one replaces burrs?
- Do we know why these exist?

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cafeIKE

#5: Post by cafeIKE »

another_jim wrote:Sorry. C_O_N_I_C_A_L.

The burrs move past each other, not towards each other, when you adjust the grind, so the sweet spots are huge
Howler Alert : If the burrs moved past each other, the grind would never change.

Assuming an equivalent pitch on the movable carrier, the burrs move an identical vertical distance for the same rotation.

Conicals are great grinders, but it's got nothing to do with the distance the burrs move. It has more to do with slower rotation, different cutting geometry, different bean cracking and fine generation. In a conical, the coffee drops into the maw and then from the burrs, rather than requiring inertia to move the coffee through the burrs.

And, oh yeah, my C_O_N_I_C_A_L exhibits the same no mans land, it's just narrower than the planar.

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cafeIKE

#6: Post by cafeIKE »

coffee.me wrote:But how come nobody says: "my grinder doesn't do 18g well", and instead they say: "my machine doesn't like to be updosed"? I dunno, this confirmation opens the door for so many questions* that I'm starting to think we're not talking about the same thing. Really? Narrow sweet spots? :shock:
I frequently find a dose suffers a meltdown and requires a drastic change, even though the identical dose on a similar coffee was delish. An e61 is very tolerant of overdosing, but sometimes I have to go from 9 to 7.5g or 12g to stop the meltdowns. Some coffees don't care anywhere from 8 to 9, whereas some are very fussy about 8.5±0.2g. I may have to adjust the temperature from 202° to 198° or ???. It's a continuum and it's impossible to adjust one thing in isolation.
coffee.me wrote:So far I'm getting "yes, grinders have sweet spots". I know that's what I hoped to hear; but it also is a confirmation that my Versalab's 15g doubles will never be amazing -- sad, really.
Why would anyone care? If it's a 15g double and nothing else, buy a coffee and a machine that gives amazing shots at those parameter. Don't be surprised if everything else goes pear shaped. :cry:

One of my favorite bar coffees is 20g triple ground on a Robur-E pulled on a Synesso to 60ml @ 202.5°F. If I try anything like that, it's hopeless. Around 8g @ 198.5°F on the MC4 and HX to about 20ml results in an equally delicious, and very similar tasting, shot.

Entirely too much rote and unwillingness to experiment pervades the espresso culture. How many times have we read "I kept the dose @ [the mythical number of grams]..." as someone wails about their meltdowns :roll: If a good shot can't be had from 7-12 or 12-20g, "It's the coffee, stupid"

"Sciences may be learned by rote, but wisdom not."
Laurence Sterne

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another_jim
Team HB

#7: Post by another_jim »

cafeIKE wrote: Assuming an equivalent pitch on the movable carrier, the burrs move an identical vertical distance for the same rotation.
Played hooky during trignometry? The more inclined toward the vertical the burrs are, the more they have to move up and down to come closer to each other. It's really hard to miss this when using two Mazzers with identically threaded burr carriers. The 12 to 18 gram dosing range on the Kony or Robur runs about 15/100 turn whereas it runs about 5/100 on a Jolly.

I'm unpersuaded by all these posts. The poorer grinders had sweet spots for all coffees on my TGP tests; none of the good grinders, including the Jolly, did. Coffees obviously have sweet spots. If this post is describing sweet spots on grinders when dealing with a limited range of coffees, it is hugely deceptive. If all you do is comfort food blend and light roasted SOs, your sweet spots will be 12-13 and 18-20 grams even on the ultimate grinder at the end of rainbow.
Jim Schulman

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cafeIKE

#8: Post by cafeIKE »

So the grind surface perpendicular spacing changing at 86% of the vertical displacement is what makes conicals better? Who knew. Give us a break

My post was about a no mans land with a usable range at either end. As was the OP. What part of "Amazing shots happen around the 20g mark and the 12g mark." is unclear?
another_jim wrote:If all you do is comfort food blend and light roasted SOs, your sweet spots will be 12-13 and 18-20 grams even on the ultimate grinder at the end of rainbow.
Gee, is that with the 57mm / 1600rpm planar or the 63mm / 350rpm conical :?: Does that mean Ken's hopelessly lost @ 14.5g :?: e61, A3,GS/3, MCaL, Europiccola... :?: sheesh

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Stuggi

#9: Post by Stuggi »

I've noticed this as well, on my very small conical i-Mini. The range between too fine and too coarse flow-wise is about 2 turns on the dial, but the good stuff taste-wise is less than a quarter tune in the middle of that. The fact that the i-mini clumps like crazy and that the ideal grind is an ever-changing target on the La Pavoni doesn't make things better. Hopefully the clump issue and some of the grind setting issue is alleviated with the upgrade to the M7 (75mm flat burr).
Sebastian "Stuggi" Storholm
LMWDP #136

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RapidCoffee
Team HB

#10: Post by RapidCoffee »

coffee.me wrote:Amazing shots happen around the 20g mark and the 12g mark. Between 14-18g, it almost always brings the worst in coffee and masks the best.
Interesting, and a bit confusing. When I speak of the grinder sweet spot, I'm referring to grind setting, not dose. Grinders with large sweet spots (typically titan conicals) are more forgiving of grind setting, and require less finicky adjustments than grinders with small sweet spots. You seem to use one definition (grind setting) when discussing vac pot, but a different one (dose) for espresso.

I'm really surprised to read these comments about dose. The vast majority of my doubles are pulled at doses in the 14-18g range, which I consider to be ideal for most normale doubles. Are you seriously suggesting that it's impossible to pull a good 15g shot with certain grinders? Maybe I'm having an attack of the stupids, but that makes no sense to me at all. Dose should be associated with the espresso machine (basket and grouphead geometry, brew water temp and pressure, etc.), not the grinder.
John