Microcimbali restoration - boiler anodic protection - Page 3

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maki

#21: Post by maki »

interesting, you had to do 3 pulls to get coffee going into cup?
LMWDP #630

XS750AU

#22: Post by XS750AU »

Pulled a few more shots this morning. My attempts at Lattes, suck. I just cannot get the milk right.
Espresso shots are very good. Not getting as much crema as on the Expobar, but the shots are deeper, richer and smoother. Very happy with them.
I am still playing around with the recipe. I think I have to back off the tamping pressure as getting the pre-infusion required 2 lever strokes, which does not seem right? :?
I did insert a thermocouple in behind the sight glass cover.


The temperature does fluctuate a little. It peaks at 101C when the pressure valve pops. It then settles and drops to 97C and the pressure valve has sealed. This cycle appears to be consistent. I am using a light roast and the shots are not burnt, they are great.
My extraction is very slow and 2 lever strokes yielded a 31gr shot. So I needed 2.5 lever strokes to get a 40gr shot from an 18gr grind, time was over a minute. That is why I guess in need more work on the grind and tamp?? :?

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TomC
Team HB

#23: Post by TomC »

I think you're on the right track. A more developed roast, lower dose, coarser grind should yield the classic Italian style shots that these were designed to produce. I wouldn't want to do a dozen rain dances in order to get an adequate volume or flavor result out of a lighter roast, on a device like this, I have better tools for those coffees.

A double pump sounds reasonable, it shouldn't require too many complex machinations. Again, slightly coarser grind, lower dose, more developed coffee or blend of coffees.

XS750AU

#24: Post by XS750AU »

I bought some Ethiopian Dark roasted beans from the local roaster this morning. I had a full schedule today, but managed to get one shot off. I had both elements on until 85C, then I turned off the 1000W element and let it coast into steady state with the 300W element. The thermocouple is not elegant, but it is very useful in getting to know the machine.
I cut the dose back to 16.5gr and move the grinder setting 2 notches finer from my Expobar datum. It took 1 stroke to pre-infuse, and then 2 full strokes to get a 34gr shot. Deep, rounded, smooth, chocolate, spice, nice shot.
So far I am happy with the results, apart from the first 2 or 3 shots when I was just establishing where the hell I was, I have not had a bad shot. Very impressed with the consistency.
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maki

#25: Post by maki »

very nice! cant wait to get my machine in the post to start playing with it (hopefully it wont break my budget with repairs :roll: )
LMWDP #630

XS750AU

#26: Post by XS750AU »

Just to confirm, I am leaving water in the boiler so that the anode remains in the electrolytic circuit. The whole idea was to see if a magnesium anode would protect the aluminium boiler. In a month or 2 I will take the boiler off and inspect both the anode and the boiler. Hopefully the magnesium anode will show signs of being consumed.