I have a Mazzer Mini grinder and have been considering converting it to a single dose grinder but have heard that the weight of the beans in the hopper leads to a more consistent grind size. If this is true, how do single dose grinders account for this? ...and would I be sacrificing grind quality if I do this?

Thanks in advance...

You will simply have a new form of consistency. It has been shown that slow feeding grinds can help improve quality. Many single dose grinders have a mechanism to slow the flow of beans into the burrs. Funnel fed grinders have a lot of variability. The amount of beans in the hopper AND the amount of time the beans have been in the hopper are two factors that can change your grind consistency and shot quality. Single dose solves this by having fresh beans dosed on demand and by having a much smaller bean weight range. When you convert to single dose you typically solve the "popcorning" effect with a top or bellows.

I have a Mazzer SJ converted to single dose and have great consistency between shots. I wouldn't be too worried about not having a kilo of coffee on top of the burrs even if the stock burrs were designed with that in mind. The quality improvement from non-variable bean weight and on-demand fresh beans will far outweigh any negative effect (if any) of not having as much bean weight as before. You will need to redial in your grind.

Hi,
Ill quote myself from a thread on a Mazzer Mini upgrade
Best upgrade for Mazzer Mini doser
-I have a Mazzer Mini with a doser.
-The Mazzer Mini is a decent single dose grinder from my experience.
-It depends on the coffee and the dose.
-With medium to dark roasts, its fine.
-If you are grinding for a dose above 14-15 grams, its fine.
-It will NOT do well if your single dose is below 10 grams.
-You can keep it relatively clean, if you want to be safe, grind 1-2 grams before to "clean out" older coffee.
-Put your tamper on top of the throat to help with pop-corning.
-Choose your favorite techniques to prep the puck (WDT, thwack the doser like crazy, etc.)

...so the Mazzer Mini doesn't have a mechanism to slow the feed since it wasn't meant to be a single-dose grinder. Are you saying that that doesn't matter?

-This is speculation from my experience.
-The last 1-2 grams will suffer from pop-corning.
-However, the larger the dose, the less this matters.
-This is part of my theory on why I have failed with 7-8 gram shots when single dosing, but 15+ grams has been fine.
-Below is a pic of what I do, this is probably why my last 1-2 grams pop corn.

My workflow includes a bellows.

-Purge 2-3g load (if first grind of the day)
-Weigh dose which is typically around 16g
-RDT (spray water)
-Load dose
-Put bellows on
-Grind
-Take bellows off
-Brush burrs with cosmetic brush
-Put bellows on
-Grind while puffing

I usually am within .1g of what I dosed doing that method with my SJ (which is similar to the Mini.) It looks like a long list of things to do but it all happens within 20s.

I may well get schooled here, which would hardly be the first time, but don't conicals that benefit more from weight as the "self centering," of the conical involves the downward pressure of the beans? (note that I'm unwilling to even make a simple statement, such is my certainty...) And, if that is the case, doesn't a feeder just mean you have a more consistent range, whereas the weight provides for a smaller range?

-I dont know the technical details, but most traditional grinders (even flat burr) were made with full hoppers in mind.
-Ive noticed it and both mine are flat burr.
-I think youre lucky with the Mazzer Mini, since it has a small and shallow opening which lessens the pop-corning.
-Keep in mind the Mazzer Mini isnt considered a big league grinder here, even though I like mine.