RapidCoffee wrote:Theoretically, I agree. In practice, a bean load of several double shots in a minihopper appears sufficient for consistent grinding. I experimented with this some time ago, and you can too. Starting with a weighed column of beans (say, 6x17g=102g), grind and dose* one shot after another until the beans are used up, without changing the grind setting. Extract each pour for a fixed time (say, 25s) and weigh the shot. At some point the extraction will begin to flow faster, and the extraction weight will increase. That will give you a rough indication of the bean load required for consistent grinding.

* obviously you need to use a fixed dose weight

Yes, this makes sense. I like the single dose idea because there's no waste, and I can change grind settings and beans on the fly. I've had shots prepared by Jim that rival the top cafe's in Chicago for taste and quality. I guess what I would want to know is whether consistent grinding (based on your example above) leads to better tasting shots than with single dosing (which would have some grind inconsistencies)?

Whether single dosing is less wasteful is open to question.

This AM I switched coffees and changed from hopper to single dosed 10.5g, 2 notches finer. The first two shots supplied 9.4 and 9.6g. The 3rd was 10.6g. Where's the 2g / 10% of the input Needless to say, the first two shots were lungo, but drinkable. In this instance, the wastage was about 67%.

When one considers there is always some remnant of the last coffee, one could argue changing coffees on a per shot basis wastes 100% as every shot contains its predecessor and is not 100% representative of the input. At what percentage the contamination is detectable is open to speculation.

The only "no waste" high-end grinder I can think of is the Versalab. With all the advice on brushing and even vacuuming out grinds from Titan-scale machines, I never thought of single dosing with them as a coffee saver.

cafeIKE wrote:Whether single dosing is less wasteful is open to question.

This AM I switched coffees and changed from hopper to single dosed 10.5g, 2 notches finer. The first two shots supplied 9.4 and 9.6g. The 3rd was 10.6g. Where's the 2g / 10% of the input Needless to say, the first two shots were lungo, but drinkable. In this instance, the wastage was about 67%.

When one considers there is always some remnant of the last coffee, one could argue changing coffees on a per shot basis wastes 100% as every shot contains its predecessor and is not 100% representative of the input. At what percentage the contamination is detectable is open to speculation.

How do you lose so much? This morning, for example, I weighed the beans going in and coming out and both weights were virtually identical. In fact, the weights were so even that after 4-5 shots, I was comtemplating not weighing the grinds, just the beans going in.

Your math doesn't make sense for another reason. Let's say for argument's sake, your grinder has a retention of 1 gm per shot. Eventually, maybe even after the first shot, that retention space would have been filled and the subsequent shots would yield what you put in. Based on your example above, where are the grinds going? On the counter? Is a bean or two popping out of the grinder? You must be losing coffee somewhere and I doubt it is related to single dosing.

*Edit: Perhaps you are losing some of the grounds in the doser? I am using the doserless funnel which makes it easy to get all the grounds into the pf.

Send coffee to a shop for testing, and by the time the baristas have it dailed in and about set to make shots, a pound is gone. Send coffee to me for testing, and I'll have it right after 60 grams max.

You have to be living on another planet or doing it wrong if you think single dosing wastes coffee. I home roast, therefore I've spent precious time roasting almost all the coffee I drink. That is why single dose.

mitch236 wrote:How do you lose so much?

It was the first two shots on the change of coffee and hopper to single. There is a cap on the throat and brushing the doser completely yielded barely another 0.2g. This grinder has only been single dosed for a couple of days a few months back when it was new. We'll see what happens tomorrow as single dosing continues.

another_jim wrote:...I'll have it right after 60 grams max

Is that 67% in 30s right or the absolute best taste for any coffee? The former probably is not too taxing for many here on a wide range of coffees.

another_jim wrote:You have to be living on another planet...

Same planet as the rest of the loonies herein ...

another_jim wrote: You have to be living on another planet....

Some days I do believe that is entirely possible.

mitch236 wrote:Something like this might work best (shower part)

How about a Mazzer Mini burr?

(I've collected a number of dead burr sets just 'cuz. I use 'em as thermal mass in my cooling tray, to suck heat out of the beans; RR45, SJ, MDX, no minis....)

another_jim wrote:Send coffee to a shop for testing, and by the time the baristas have it dailed in and about set to make shots, a pound is gone. Send coffee to me for testing, and I'll have it right after 60 grams max.

About the same for me if it's a brand-new coffee I haven't tried. It takes only one or two shots if I've pulled the coffee before. The K10 is amazingly consistent.

Retention is very low, too, if you take the time to pulse 3-4 times and brush out the chute. On average it's about .5g or less, though sometimes higher on the first shot of the day when ambient humidity is high. I doubt that makes a lot of difference when changing coffees, but if I'm really concerned about it I'll grind a gram or so of new beans to clear out any of the old coffee that may be lingering in the burr chamber. I don't consider that one-time sacrifice particularly wasteful.

Day two and I'm finding my starting weight to be so close to my ending weight (before and after grinding) that I will probably end up merely weighing the beans and just grinding. The only problem with that is the scale has uses beyond weighing:



It is a great shelf for my basket!!

BTW, the consistency is very good. I don't use anything to compress the top of the beans since the auger seems to do a good job of minimizing popcorning but I did put a shot glass above the column to avoid losing a jumping bean!