I now have a beta unit and will start breaking it in tonight. I don't intend to post regular updates here as I test it out, but I'm happy to answer questions. Reminder: I don't do espresso at home (yet).

jbviau wrote:I now have a beta unit and will start breaking it in tonight. I don't intend to post regular updates here as I test it out, but I'm happy to answer questions. Reminder: I don't do espresso at home (yet).

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Great! I'm considering pre-ordering one.
Could you please post a picture holding it in your hand? How is the adjustment, doest it have resistance? How is the adjustment lid kept on, could you show the underside of it and inside of the grinder's top part?
The cut-out in the handle looks like it might also open bottles

I'd love to see some photos beside the Feldgrind and hear your thoughts on how they compare.

Will it pepper?

(Seriously. I've never lost interest even if the idea.)

^^^ No pepper will touch this grinder. That's what the Rosco is for, right?!

Limited time tonight, so I'll just post a few quick comments and do a photo dump.

I did four 25-g. grinds at various grind levels. Smooth but somewhat more effortful than with the feld, which is probably due to a combination of newness and a shorter handle. The setting never slipped, so there's adequate resistance. The lid is a press fit.

Re: finish, the Aergrind is a step up from the feld. No glue on the inside or other blemishes at all aside from the uneven anodizing on the interior of the catch cup, which IIRC is a known issue that's already been addressed. Very tight build. I was surprised by the lack of a spring above the cone burr! With the feld I'd picked up the habit of clearing ground coffee bits from in between the burrs by pushing up on the cone burr from underneath, but that's no longer possible.

More soon...

Thanks! So the grind container is made from a single piece of aluminum, right? No plastic bottom?
Is it possible to use the handle from Feldgrind?
Thanks again!

Great that Joshua posted some photos! I've been in Aergrind beta test mode for one week, but have not had time for photos yet. I have had time to brew espressso though, and all of my shots had been ground on the Aergrind. Shots pulled on the Sama Lusso with a bottomless portafilter. I'll add that I have been pulling 3-5 shots daily with hausgrind number 001 for 3 ½ years now, and hand-grinding with vintage grinders daily since 2005 (some 12,000 shots).

First impressions:

Right out of the box the shots were great - literally no sink shots and not spritzers. I adjusted the burrs to espresso based on estimating the space between them by comparing to my hausgrind. I think I ended up about 1,5 turns past zero on the well-marked hopper cover/burr adjuster dial (I haven't dialed it back to check). Visually, the burr alignment seems great - I have no idea yet how this can be adjusted if needed. The grind adjustment mechanism is simple and elegant, very nice innovation. I have made only slight adjustments (1-2 ticks on the dial) over the course of the week, so the grind setting is precise (ie, no drift of setting and low variation in grind qualities). So with your favorite blend it will be "set it and forget it" more or less. I cannot comment yet of switching between espresso and pour over.

Mine came with a little coffee dust in it, so it had been tested, but I doubt "broken in". I found no need for any break-in period, since the shots are pouring great from shot #1 and I have had little need to adjust the grind setting. I recall having a slight break-in period with the hausgrind where I would get an occasional spritzer - perhaps the black burrs on the Aegrind are more finely finished? The Aergrind is currently slower for 18g than is my hausgrind - perhaps speed will increase with break-in. Both are well within "easy" range for 18g, however, less than 30 seconds I guess.

Grinding ergonomics are very good - as with all my hand grinders I like best to hold it with my left hand and brace the grinder between my knees while sitting. The cylinder is the correct size for my hands so it is very comfortable. The height is just enough to get a good brace with the legs - any smaller and this would be difficult. Super easy to grind the northern Italian espresso blends I use - have not tried any light roasts. (I pause here to grind a prep the morning's first cappuccino - excellent, but more on that later). The removable grinding arm is long enough to provide easy grinding leverage. It is shorter than on my hausgrind though, which is even easier to grinder with. The grinding arm grind-adjustment indicator dial doubles as a bottle opener . The small plastic knob is quite comfortable to hold while grinding, so no issues there.

The hopper easily accommodates the 17-18 grams of beans I use for a double - I have not measured the maximum capacity yet. The catch cup will hold more, but not a lot more (25-30g perhaps?). The catch cup fits securely via a rubber o-ring and I don't anticipate any issues with it falling off. No static at all with the beans I use, and given the climate here, but I also always use a drop of water on the beans (RDT). The grinds "appear" very uniform to the naked eye (no testing) and I dose directly from the catch cup into the PF basket.

Absolutely clumpless dosing is made easy with knock grinders because of the cylindrical catch cups - if one revolves the catch cup while dosing it gives a "cement-mixer" effect of tumbling the grinds, which eliminates any clumps that might have formed. In general hand grinding (low RPMs) plus RDT results in near-zero clumping. With knock grinders, revolving dosing eliminates the occasional clump. The resulting highly-uniform distribution of grinds makes uneven pours and spritzers the rare exception to the rule of excellent bottomless pours. The Aergrind follows suit here.

Taste-wise, there is no perceptible difference between the hausgrind and the Aergrind, nor would one be expected. They use similar burrs and the grinding speed and puck preparation processes are very similar. I have no large-burr conicals or flat-burr grinders to which to compare them. All I can say on the taste comparison front is that the espresso I brew at home with knock grinders is easily as good or better than 99% of what I've had at cafes, and that everyone who visits me likes my espresso better than most other espresso. So practically, the Aergrind makes an excellent espresso grinder.

To sum up the functional aspects, I don't see what more one could possibly expect from a hand coffee grinder. Alignment is fine, grind adjustment is excellent and ergonomics as good as possible for a travel grinder. I'm sure others will wish for certain aspects to be different - there is no one-size-fits-all solution to everyone's grinding needs. If I discover new aspects I'll post about them.

Aesthetics:

Aesthetically the Aergrind surprises - I'm a lover of wooden implements including hand grinders, and so was skeptical on the aesthetic front. Although the Aergrind would not easily replace my beech hausgrind, it is still a joy to use. The anodized black finish is very smooth with no visual blemishes. It has a quietly-refined visual aesthetic, like most knock (note, not Knock) grinders. Peter Kilpatrick, founder of made by knock, is keenly in tune with aesthetics, as a glance at his Instagram page reveals.

What is most dynamic is the tactile aesthetic of the Aergrind. Residing where it does at the absolute minimum size range for a coffee grinder (it's smaller than my salt grinder), it packs so much energy into this small finite space. The burr-mass to body-mass ratio is extremely high - I doubt any other grinder body weighs less in comparison to the burrs. The Aergrind is essentially ALL burr. My hand is separated from the outer burr by a few millimeters of metal to which the burr is integrally-fixed. This means that I can feel the beans being fed through the burrs as I can with no other grinder, even the hausgrind (which has its own unique tactile aesthetic). (Here I pause for cappuccino number two - WOW - the roast beans cocoa flavor on this one punches through the milk).

For me, hand grinding has always been an integral aesthetic part of the espresso experience. The energy that I transfer to the grinder with my body is reciprocated as the beans are broken down. Because the Aergrind is so diminutive and integrated, more of that reciprocal energy is felt while grinding. Even after 10+ years of grinding espresso exclusively by hand, I was surprised by the Aergrind in a very positive way.

Few people probably consider tactile aesthetics on the top of the list when choosing espresso equipment. To fail to do so is to underappreciate the extreme importance of felt experience in our everyday lives. Many philosophers agree that human bi-pedalism was a key evolutionary leap in the intellectual development of Homo sapiens. When we began to walk on two legs and our hands became free to manipulate our environment, an amplifying feedback loop was created between hand and mind. The more and newer things we made the more intellect we built to interpret and improve them. Thus our sense of touch can have such powerful meaning in our lives.

I think the experiential aesthetic aspects of coffee have been severely de-valued in the quest for "bigger and better" - the physics of grinders in particular have been the focus of much scrutiny, with little real attention being paid to the quality of the experience. The coffee forums, in fact, reflect this, as they have become largely boring accounts of measuring trivial variation in physical parameters that has little or no real meaning for the coffee experience. Coffee is a plant and a food, and the quality of its experience is greatly affected by how it is prepared - the mechanization of its preparation can detract from its overall value. For those people curious about the aesthetic aspects of the coffee experience, the Aergrind is an excellent choice.

Yes, the catch cup is machined from a single bar of metal.

Great write-up, thanks!

pre-ordered