Nate42 wrote:The basket isn't meant to / doesn't need to have a snug fit with the portafilter. I doubt it would make much difference, but personally I do all my leveling and tamping rituals with just the basket anyway.

I have now started doing the puck prep by just using the basket too. No more wiggle. I can move on to the next obsession

jpender wrote:I don't understand it either. And while it seems plausible I'm not entirely convinced by the mostly hand waving arguments about the basket shape. I can't try other baskets in the Robot. For me it seems to correlate with the particular coffee. I brought a kilo of a medium roast back with me from Australia and never saw the donut with any of the 50+ shots I pulled with that coffee. Then I went through about half a kilo of the darker Italian Saka and got a donut the vast majority of the time. There's a Blue Bottle dark roast (Hayes?) that would ALWAYS do this no matter what I tried. I *think* darker coffees do this more although I haven't been keeping track. And I have no hypothesis as to why that would be the case.

It doesn't seem to matter though so... you know.

I confirm your theory about donut pre-extractions depending on particular coffee beans. I have changed this weekend to washed Guatemala beans and the donut is pretty much gone

In my experience, I don't see a correlation with darker beans though, but I do see it changes depending on the beans

Thirding this. The donut is entirely a matter of the bean. Despite my prep being the same for all beans, some beans donut and others do not.

With pressure gauge (that I would have to move because originally not very readable), it helps to define the extraction profiles. This is finally the observation I make, especially for medium roasts. With this one for example, it doesn't matter how long the extraction takes and I start slowly for about 20 seconds, etc. But what I wanted to ask: are there any web sites that offer profiles in terms of pressure? Decent users should do this, or others (La Pavoni, Robot maybe, flair, etc.). Anyway, if you know of such a web page I'm interested in checking it out (maybe on the forum).
Thanks

I was gifted pre-ground "espresso" roast level beans that were ~1 month post expiration date. The chocolate oat milk was on steep-discount sale, and I've never had it before (surprisingly tasty, not cloying sweet at all!). Regular basket, cold milk, just let gravity do the work, otherwise the robot choked.

This took me back to mocha-frappacino days

Any of you playing/played with other infusions?

Hi all,

Curious to get some feedback from anyone willing to help. Im trying to improve the espresso I'm getting from my robot.

At the moment it's coming out very thin, and with next to no crema. I'm hoping to pull thick, traditional style ristrettos with lots of crema.

I'm using about an 18-19g dose. I'm pulling medium home roasted Sumatran beans 5-7 days off roast.

I definitely botched the last few roasts, but I can still get a tasty (albeit slightly burnt/baked) shot off my 9barista. I noticed my 9barista tends to take a bit more of a coarse grind compared to my pump machine.

In turn, I've tightened up the grind for the robot. I can tighten it up more, but I'm grinding pretty fine. At the moment I'm trying to pull with my atom pro.

I did not splurge for the barista version. So I don't have a pressure gauge. May look into buying it separately from eightounces. Today I put a bathroom scale underneath the robot and found I was probably hitting about 25lb of force at peak. I eased up slightly after I hit 1:1 and the shot still ran a bit on the fast side.

My water is likely too hot as well, as I'm pouring it in to the portafilter 2-3 minutes off boil whilst it sits in the hot pot. There is steam coming out the bottom of the portafilter, and the espresso is very hot. Not good. I may pick up a cheap frothing thermometer for the water.

What else...I'm very slowly wdting. My puck prep could certainly improve, but I'm trying to be careful, and tamp evenly/firmly. I haven't measured the tamp force. May have to do that next time.

I'm using a paper filter on top of the puck, underneath the stock metal screen.

I am heating up the robot using the dc heater I put in. I keep the portafiler and basket in for 10-15 minutes. The piston is warm, but definitely not hot by any stretch. So I don't think this is much of a factor.

Flair Classic Force vs Brew Pressure

All else being equal I think I need to tighten the grind further? At least based on the above link? Maybe up to dose too since my burrs are unimodal?

Any criticisms are more than welcome as I'm a bit lost with this machine. Ty

I don't know. But here are a few observations.

Your 9barista has a different basket diameter. Maybe you need to grind finer for the Robot. You didn't mention how long the shots were taking.

25lbs on a bathroom scale equates to about 4bar, kind of low. Push harder / grind finer.

Boiling water straight into a Robot equates to roughly 91-92°C with a fairly steeply declining profile (e.g. 2°C every 5 seconds). Preheating the piston so that it is a little warm just means that the temperature will decline a little bit slower. Not a big difference.

Try using better beans first, figure out the machine, then work with problem beans.

By comparison, I was getting good shots with my Robot on day 1. I had never used an espresso machine previously.

FWIW

Thanks for the thoughts John.

The beans aren't the problem. They aren't my best work, but I can still get tasty shots from them on other machines. I've been roasting them for a few months and I know they aren't a disaster when compared to some of my good roasts.

Appreciate that if these are over developed, then I need to grind finer on that point alone, when compared to my good roasts. But they are far from dark, or oily.

The quick shot today ran about 20-23 seconds I believe.

I agree the pressure seems off. Maybe that means grind finer, but maybe I should also up my dose.

I had a not dissimilar experience using K8 burrs on my ceado. While I appreciate that the atom pro is pretty unimodal, and fast flowing, the upper and lower ends of the grind range I use on my ceado also yielded the same type of results.

I'll try going close to burr chirp and see what happens.

buckersss wrote:My water is likely too hot as well, as I'm pouring it in to the portafilter 2-3 minutes off boil whilst it sits in the hot pot. There is steam coming out the bottom of the portafilter, and the espresso is very hot. Not good. I may pick up a cheap frothing thermometer for the water.

Highly doubt that your water is too hot with that kind of cool off. Do you have a good digital instant read thermometer? Analog instant read is not really instant read. Either way, try a shot right off boil.

Here is a chart from a Robot manual that shows the equivalent bar to pound on a scale.

https://www.manualslib.com/manual/19947 ... =23#manual

Ken

Wow thanks very much Ken. Good to see that, I'll give the manual a once over now too.