Hi everyone,

curious which of the below you'd prefer:

1. single dosing system, like a HGOne or a Versalab - you weigh the beans yourself and drop them in the grinder

2. hopper based system - with an electronic scale which weighs the grounds and stops the grind at the right point. This would be similar to the E series of the Mazzer, but rather than being time based, this would actually weigh the output (don't think there's anything like this on the market at the moment).

I guess both of the above have their own pros and cons:

1. pros:
- no waste if you run a low retention grinder
- no stale issues as you can keep the coffee in a tight container and dose as much as you like at a time

1. cons:
- time wasted to weigh the coffee
- weighing is an additional step in your routine which might annoy some people

2. pros:
- easy of use
- takes away a step from your routine

2. cons:
- coffee goes stale in the hopper if you don't grind too often
- variable grind size due to variable pressure behind the beans

I've never thought about this, but for home use option 1 is probably much better than 2. You've got less of a chance of using stale beans, no left overs to worry about, no variable grind size to worry about if you're running low on coffee in the hopper, no problems when changing coffees. For cafe use option 2 would probably be preferred as they quite often run the same coffee / blend for a few days, don't change coffees between shots (if they offer more than one coffee, like a blend and an SO they have two grinders) and they can run through a lot of coffee in a day.

Anyways, which one would you like at home and why?

Regards,
dsc.

Tom,
Great question! I was actually going to write up and post my thoughts on this.

My background: Mazzer Major E 83mm flat burrs and HG one 83 mm conical burrs side by side.

I have never succeeded in single-dosing the Major.
Full hopper/precise timer/antistatic screen is the best way to operate it.
It gives very consistent results, ease and speed of use.

I really enjoy my HG one now, the best part being ability to prepare "espresso menu", I store many varieties of beans frozen in very small batches only several shots worth. Would you like some juicy El Salvador Ignacio Gutierrez Natural Pacamara COE, followed by sweet Brazilian Tijuco Preto Carmo De Minas and finished with dried dark fruit bomb Ethiopian Yirgacheffe Wote? No problem!
By weighting beans and having no waste I literally drink every single bean I buy which is great.

First issue: "fines production"
When single dose you need to grind finer. For same setting (= burr distance) single dosing produces faster flow then full hopper, possibly because of different particle size distribution due to lack of bean to bean crashing forces, and let my assume, it produces LESS FINES.
It might be more of an issue for flat burrs then for big conicals, that's why l do believe that big conicals are better suited for single dosing.
As different coffee beans vary in fines production, some are more forgiving and easier to pull then others. Some flavorful high grown lightly roasted acidic coffees produce so little fines that they are almost impossible to pull and extract well. Full hopper might help.

Second issue: Grinds "post processing"
It was though that if you get fresh grinds directly from burrs and don't manipulate them much, it will give you best results, no, doesn't work!
One extreme is: grinds are hit in the burr chamber by vanes, smashed, compressed and propelled out at high speed through chute to the doser, propelled around it by furiously clacking barista, massaged into the basket by Stockfleth's moves and finally tamped down. Result? Great even extraction.
With HG one coffee powder lacks that "post processing", free falling grinds are not good. You need to mix/shake/stir/distribute them to get good even extractions results. This is major issue in retention-less grinder design.

Grinder capable of good single and hopper dosing with ability to switch between these two easily and mixing grinds well after they exit burrs, that is real goal!
As for now, I will enjoy my Major/HG one duo on the countertop.

Single dose.

No waste
No stale coffee
Unlimited Variety
Easy to change grind setting
Easy to Change dose
Guaranteed to be consistent every time.


In the scenario of drinking the same coffee for a couple weeks at a time, AND IF you own an Elektra Nino or Mahlkonig K30, THEN I could see an argument for loading up a hopper. But ONLY in that scenario.

I do have a Mazzer Major converted to an E series, so I do agree with a half full hopper and antistatic screen, it's simply the way the grinder was suppose to be used. I believe that in the end it all boils down to how a machine was designed.

You mention the lack of 'post processing' with the HG One, do you still have issues without WDT if you get no static problems? I know from limited testing that static affects fines really badly (smallest particles stick to everything easily as they are the lightest), so with static problems I can see the grind needing a 're-mix', but I'm not sure how well the shots pull when all grounds end up nicely in the basket.

Jeff, why are you only considering the K30 and Nino? What if you had a grinder which is one level above those (it weighs the grounds) and has zero retention.

Regards,
dsc.

Well, realizing the Baratza Vario-W is not quite[x] a brute compared to the Big Mazzer e's, I've found it grinds about the same single dose or with half a hopper.
I feel a 1/4 hopper works fine, but after a few shots, I can change to another coffee if desires.

#1

I've done both with my Robur-E and here's my findings:

Single dosing adds more time and fuss and is prefect for the user that wants low waste with the ability to pull different coffees back to back.

Hopper dosing is fast and easy, the timer is usually accurate to 0.5 Gm and is perfect for the user that uses one coffee at a time. You still will waste much more coffee than the single dosing method.

dsc wrote: You mention the lack of 'post processing' with the HG One, do you still have issues without WDT if you get no static problems?
...I'm not sure how well the shots pull when all grounds end up nicely in the basket.

Even without static issues, when coffee powder is allowed to "free fall" it gives an opportunity for variously sized particles to separate. As powder is falling on top of the growing mound, larger and thus heavier particles are quicker and prone to fall/roll of the mound and accumulate more to sides. Smaller particles and fines are stickier and stay together closer to the center. Static can separate fines even more, and make things worse. HG one creates really nice symmetrical hill of clumpless powder in the basket, but without "post processing" naked extraction is a horrible mess.

Creators of the HG recommend to stir grinds, and they have confirmed in our email communication, that without stirring/mixing, they observed "very distinct donut extraction".

Actually my modus operandi is to grind to the paper cup (or any other container if you like), light shake or stir, and pour powder to the basket. Little shake or other method to distribute flat (more or less), tamp and go for really nice symmetrical extraction.

I think Pharos users actually do "post processing", by knocking powder from it, or in moded Pharos by grinding to the container and redistributing grinds to the basket thereafter. I don't have personal experience with Versalab, but that "static wiper" thingy may actually provide some "post processing" and even mixture of particles.

David Schomer describes his thought on particle distribution, "free fall" etc. in his blog here:
http://espressovivace.com/schomerblog/i ... g-systems/

As about weighting system design for dosing: I find my Major with precise electronic dark room timer to be accurate to as much as 0.2 grams, many times it would be even dead-on precise on back to back shots. I actually use timer (=dose) adjustment to correct flowrate more often than grinder fineness. I don't care if my shot is made from 16 or 17 grams as far as I maintain desirable extraction ratio. After checking myself with scale, I have found that I stop most of my pours based on their visual appearance in the range of 65-75% ratio. I don't think weighting system will bring more benefit than complexity over precise timer.
When dialing in coffee on HG one I use same dose and adjust fineness, just because it is easier and you have immediate effect, where on Major with full hopper, it would take a shot or two to grind through to new setting.

Thanks for all the replies, below is a few things I wanted to comment on:

1. single dosing - nothing beats this method if you want flexibility in coffee changing and you have a grinder which has low retention. The main issue here is work flow, every single time you think 'coffee time!' you have to grab the scales, grab a cup, weigh the beans and then grind. For some this is nothing, purely a few second task which you get used to, for others it's a pain, an unnecessary step which should be eliminated by clever engineering. I guess it all boils down to how you think and which group you belong to.

2. weighing vs timer based grind - I think the only weighing grinder currently on the market is the Vario - W, which as Robert says, is not a titan type grinder. I know one can get good results from precisely timed grinding (first hand experience), but it's a pain if you frequently change grind settings, which mostly happens when you switch coffees. Then again if you do that, a hopper based grinder is not great anyway, so the whole weighing / timing system can be ignored then. Weighing has it's advantages and I see it as a higher level system than purely timed grinding. Even small tweaks to the grind settings will affect your timer settings, coffee going stale will affect your timer settings, trying to keep the dose the same and grind finer / coarser will affect your time settings. With a weighing system all you need to do is set the correct value and off you go.

Robert, how do you find the Baratza Vario-W? how precise is it? would you decide to buy a grinder which offers zero retention and a weighing system?

Michal, thanks for the info regarding the HGOne and additional links. Versalab seems to be the only zero retention grinder which allows to simply grind, tamp and pull, without touching the grounds. Curious if adding a Versalab 'wiper' to the HGOne would make things better?

Regards,
dsc.

JmanEspresso wrote:Single dose.

No waste
No stale coffee
Unlimited Variety
Easy to change grind setting
Easy to Change dose
Guaranteed to be consistent every time.


In the scenario of drinking the same coffee for a couple weeks at a time, AND IF you own an Elektra Nino or Mahlkonig K30, THEN I could see an argument for loading up a hopper. But ONLY in that scenario.

AGREE!

I see how much waste my friend endures with his K10 Fresh, and how inflexible the commercial grinders are when they are stock and I never wish for one second that I could have back all of that extra time I spend single dosing my K10.

Because there has been no evidence to support that the two methods of dosing your grinds make a difference in the cup it literally all comes down to user preference. You have to make certain adjustments to go between the two methods, but you can make the same product with either.

There's been A LOT of discussion around grinder dosing on these forums.