I took the grind coarser and seem to have a faster flow rate. In my few tries there was no crema, but I didn't expect much. My impression is that these coffee makers create a brew similar to a moka pot without easily overheating and with some more delicate flavors revealed. I will experiment more, including with the steam equipped version Cher is sending me.

Sorrentinacoffee says he gets some crema with his new baskets. I wasn't expecting much and am more concerned about flavor, which Atomic seems to deliver better than my Bialetti. Just reporting what I experience. And, if the water was delivered to the brew chamber at boiling temperature the coffee would taste burnt, which it doesn't.

drgary wrote:I took the grind coarser and seem to have a faster flow rate. In my few tries there was no crema, but I didn't expect much. My impression is that these coffee makers create a brew similar to a moka pot without easily overheating and with some more delicate flavors revealed. I will experiment more ....

Today I coarsened the grind further, filling the basket to the very top and keeping the heat quite moderate. I pulled the jug away, replacing it with a silicone catch cup just as extraction started growing weak and before it went bitter. At that point steam could be heard at the group head and the coffee in the catch cup was slightly bitter, thus apparently overheated or overextracted with a lower flow rate because I had turned off the heat. No matter. I wasn't expecting to drink it.

The taste I am getting now is a concentrated coffee (somewhere between normale and Americano), rich with caramel and very good for a milk drink. I will try lighter roasts for more delicate flavors. Please keep in mind that I am reporting results as I dial in what is a new brew method for me.

I was thinking of adding a paper filter as I have done years ago with current higher pressure machines. I also use a filter when making a moka pot, creating a very clean cup. Last night I read about using a paper filter in the American patent. I have noticed some uneven extraction, which might be lessened with filter paper above the basket. This also tells me, though, that I will grind coarser still and will do a very light tamp to ensure even distribution.


* Since Jack has gone to the effort of manufacturing a fine replica of the original Atomics, and he offers filter baskets with smaller holes to enhance pressure in the brew path, I will keep reflecting on what he has written, including his crema discussion that was challenged in an earlier thread on H-B. Because I don't care much about crema in this brew method, my focus is more on the idea of experimenting with higher pressure for taste and for improved steam power on machines equipped with a steam tap. I have also considered using filter paper at the bottom of the basket to slightly enhance pressure and reduce fines in the brew that could yield some bitterness.

I just tried a somewhat lighter home roast of Rwanda coffee with a coarser grind. The flow rate is not as fast as I would like it to be. But it did reveal more of the flavors in the coffee and I enjoyed drinking it without adding milk or sugar. I will go yet coarser.

Discussion of who is producing what machine called Atomic or otherwise and the various trademark and patent arguments can be found through an internet search. I will keep that to a minimum here because it would distract from understanding a classic brewing device. In this thread I am referring to the early generation of machines labeled "Atomic" and most widely known in the configuration seen in the machine whose photo I posted earlier.

Back on topic, I will continue with exploring how to best brew with my Sassoon Atomic.

Further experimentation with the Sassoon Atomic today with adjustments to the grind and paper filters added above and below the portafilter yielded an "emulsion". The discussion in USA patent 2,549,132 mentions adding a filter paper to the bottom of the basket to reduce fines in the cup, so this is a message recommended by Robbiati himself. I added the paper filter on top both to try and increase pressure, even out distribution from the shower screen, and prevent grounds from washing back behind the shower screen. The emulsion isn't buttery crema the way we know it with higher pressure extractions, and it dissipates very quickly, so I don't think it adds much. The coffee was a very tasty moka, though. The first image is a still pulled off a video.




Cher's wonderful gift arrived today. I look forward to checking out its steaming capability. It has a filter basket with holes in a six-pointed star. The badge is in great shape!

Thanks for your fearless testing, Gary. I think stove top moka has its place the coffee. As you mentioned, the taste is a nice caramelized coffee profile that I really dig. I would be interested in trying some Indian Monsoon to see how it accents the 'sandalwood' profile. I've been loving Burman Coffees' Haitian Blue Mountain (incredible shots, IMHO) and would be really curious to see where else that profile could go. I better get my Atomic up and running.

drgary wrote:This is "espresso" in the older tradition of brewing coffee under pressure without a pump or piston. Done properly the brew water is below boiling temperature and the resulting coffee is concentrated.

Just curious -- how concentrated is the coffee?

It can be quite concentrated, depending on when you stop the shot. Haven't measured yet. As I wrote earlier, this is more between a normale and Americano, usually Americano.

That's a wide range!

I would love to play with one of those. But they appear to be rare and expensive.

A fixer upper sold on eBay for about $55 shipped a couple of weeks ago. It would not be as pristine as what you see here, but you can get them at better prices than complete ones in great condition.

I heated the "2,8 Kg aluminum lump" sent me by Cher today and made two excellent capps. Again I used filter paper at the bottom of the basket and the top. Paper at the bottom creates a cleaner cup and makes it easier to build pressure. Paper at the top is to avoid coffee backwash above the shower screen. Steaming isn't intense but creates good microfoam. I'm not aiming for crema, just good tasting moka pot coffee as the basis for the capps. I used a dark roast barely taken to second crack and the coffee wasn't burnt, because I swapped in a catch cup when it started to go bitter, using a spoon to taste the coffee stream. I couldn't tell the taste difference between these capps and others I've made with my lever espresso machines. To steam, one waits until steam starts coming out of the group instead of coffee. The coffee in the portafilter helps retain steam pressure, and there's no need for the brass rod people sometimes use for that.

To get the Robbiati steaming Atomic ready, I had to do some intensive descaling. When I tried to brew at first, only steam would exit the group, not water, so I figured out the brew pipe must be clogged. I removed the shower screen and emptied out lots of white scale crystals. Because of this I used vinegar instead of citric acid, which can harden into its own precipitant. Scaling was achieved with three runs of 50/50 water/white vinegar to fill the jug, and then thoroughly rinsing the machine by running water through it and using the steam tap with a blind basket stopper I use with my Olympia Express Coffex. It fits perfectly as does an Orphan Espresso dosing funnel because the portafilters on these are for a 49mm group. The blind stopper also helps should I want to use the machine only for stovetop steaming.

I tried to remove the boiler plug without being able to budge it and make sure the pipe was thoroughly cleaned as is suggested in the Sassoon manual. Since I'm able to descale, I don't think it will be necessary. Here's a photo of the stuck plug. It looks like the plug was fastened onto an aluminum crush washer, which is why concentric rings are visible. The model A Atomics have no plug, so I'm thinking I will let well enough alone.



Here's the Sassoon plug, by comparison: