# Getting a decent single shot from my new Cherub...



## Kev1888 (Jan 5, 2014)

Hi to everyone and I'm looking forward to hopefully getting the benefit of your experience to help me on my way. My new Cherub plus Rancilio Rocky doser-less arrived last week and I've been feeling my way around it ever since. I read many reviews before buying so I'm comfortable with my purchase.

My problem has been trying to get a decent single shot poured. I've had many variations from fairly thin minimal crema to water leaking (quite often) from the group head, to no extraction at all. I've tried variations in grind (from 4 to 10 on the Rocky) and in dosing (7, 8, 9 grams) and tamp pressure without any real results.

i was wondering if the standard single basket supplied with the Chrub has anything to do with it? (Other than the obvious common factor...me!). Has anyone else had similar single-shot issues? The double shot seems to be much more consistent. What about different baskets? Or a bottomless one?

I appreciate any feedback and help you can provide.

cheers


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## 4515 (Jan 30, 2013)

I only use a double basket - dont think that the single basket has ever graced my portafilter.

Cant really help other than saying that I found that my shots were a lot more variable before I bought the mythos. I seemed to be forever adjusting the grind / tamp and experienced similar issues - fast pours, no pour at all, slow pours. This was with the same bean on the same day

I dont think that a VST basket will cure it (didnt for me) but it will look pretty.


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## Mrboots2u (May 10, 2013)

Hi there and welcome.

Single baskets are harder to fill and use due to their size , different walls and what you need to tamp them with.

Getting consistent extractions is about changing one variable at a time ( it can be ground , or dose or tamp ), but only change one . When dialling in a bean I'd stay with a double basket too.

As the rocky is a stepped grinder then you can change extractions times by increasing or decreasing the dose used if you are stuck between steps .

Also measuring your input and output by weight will help get better results (use cheap jewellery scales )

A naked PF will help you improve your distribution in the basket, help you see where the distribution is uneven and whether there is any channeling or unevenness . This will cause quicker pours or sourness in taste .

Once you have all these nailed then I'd move onto a vst basket if you feel you want to try the out .

Hope this helps .


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## Kev1888 (Jan 5, 2014)

Thanks for the quick replies guys. I think i probably am taking on too many variables at one time... Good advice to change one thing at a time and see the results (probably too impatient!). Incidentally what would you say is the ideal extraction time? Between 25 to 30 seconds? When I begin the extraction process (double or single) i don't see any flow until around 7 or 8 seconds in. Is this normal or perhaps a symptom of over tamping / too fine a grind?

thanks


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## Mrboots2u (May 10, 2013)

Kev1888 said:


> Thanks for the quick replies guys. I think i probably am taking on too many variables at one time... Good advice to change one thing at a time and see the results (probably too impatient!). Incidentally what would you say is the ideal extraction time? Between 25 to 30 seconds? When I begin the extraction process (double or single) i don't see any flow until around 7 or 8 seconds in. Is this normal or perhaps a symptom of over tamping / too fine a grind?
> 
> thanks


Hi. Get some cheap jewellery scales , measure the dose into the basket say 16g in a double , then aim to get out 25-26 ish in around 25-30 seconds . Check the taste and see if you like it . If your hitting that measurement 25g too soon the go finer , or up the dose a bit if inbetween your steps . Try and keep the tam pressure repeatable and the same .

Taste your shots ,a re they bitter , sour ? What does the crema look like pale or really dark. Experiment and have fun and tell us what you find . These taste flaws canbe down to extraction or temperature of extraction.

Remember if you change blends or benan then this will change the grind needed , so try and get bunch of something you like .

One last question , want beans are you using re they fresh roasted ( with a roast date on ) ?


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## Kev1888 (Jan 5, 2014)

Thanks MrBoots, i have been using a set of digital scales to measure the dose (though I've no idea how accurate they are?). Didn't consider measuring once extracted... Is 25 grams the weight of the volume of espresso for the ideal single shot (excuse me for asking what may seem obvious question but I'm new to this)?

I get my beans from a local supplier who I would recommend (see pic) though there is no obvious roasting date on the package. I usually buy 6kg at a time which lasts a few months.

cheers


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## Mrboots2u (May 10, 2013)

Hi there . I would ask when the beans are roasted as beans can start to lose their flavour or and freshness after say 3-6 weeks after roast ( this timescale is only opinion thou and will depend on the beans used anyway ?

If he doesn't know when they are roasted then that would make me raise an eyebrow somewhat , as they could have been sitting there 4 weeks before you buy them . 6 kg is a lot to buy and if your still using the same lot say 3-4 months after it won't be fresh. How are you storing them , or are you freezing them ?

It's better to buy some a couple of week worth at a time and keep getting fresh beans , than stock pile a few months worth .

As the beans age , you will find that the extractions get quicker and your making the grind finer and dosing more to compensate, along with losing their taste


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## Kev1888 (Jan 5, 2014)

Thanks, Blue Coffee Co do all there own roasting so they can tell me when they were roasted. Maybe buying 6kgs at a time is too much given the freshness issue...i think i just have to accept that I'm going to have to waste a lot of coffee getting things right in the effort to get better coffee!


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## Mrboots2u (May 10, 2013)

Don't worry , everyone wastes a bit of coffee with new beans or new gear . Re shot volumes if your dosing 16 g the aim for a extraction weight if 25-26g that what I would out in a drink. I don't look at the volume per se ( single or double shot ) .

Looking at extractions by volume can be inaccurate due to crema levels of different beans they way crema subsides etc.

Give it a go .


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## Kev1888 (Jan 5, 2014)

Thanks again...will give the extraction measurement a go, should be interesting

cheers


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## xiuxiuejar (Jan 24, 2012)

I was in Canterbury over Christmas and a young lady was selling espresso made from a Fracino and SJ and I was quite impressed. So I imagine that with a bit of practice you'll get excellent results. I commented on how nice her equipment was before we had a little chuckle at my faux pas!


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## Kev1888 (Jan 5, 2014)

Thanks again...will give the extraction measurement a go, should be interesting ?

cheers


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## Kev1888 (Jan 5, 2014)

xiuxiuejar said:


> I was in Canterbury over Christmas and a young lady was selling espresso made from a Fracino and SJ and I was quite impressed. So I imagine that with a bit of practice you'll get excellent results. I commented on how nice her equipment was before we had a little chuckle at my faux pas!


Thanks, the Cherub seems very capable and very well built, it's only the dumb operator that needs to polish up..! ☺


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## xiuxiuejar (Jan 24, 2012)

There are 2 ways you can go, you can be exact with your measurments or you can go more or less. I tend to do everything by eye as I know what I like but if you're having problems then the best way is to weigh, time and measure. Have you got a shot glass? This is the best way to control your output as you pour as it is a visible marker. You could of course just mark off a normal glass/cup. Then, I would measure 9g for a single and 16 for a double basket. It is correct that it takes 5-9 seconds for the first coffee to appear. I'd also time 23-25 seconds for a single and 27-28 for a double. Remember to use a slightly finer grind for a single. Once you do this a few times, you'll just do it naturally.


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## Mrboots2u (May 10, 2013)

Once you got the hang of stuff you an go by eye , look at when the extractions blondes and pull by eye . If new gear , new beans , new grinder , weighing is a good starting point to help out .


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## Kev1888 (Jan 5, 2014)

xiuxiuejar said:


> There are 2 ways you can go, you can be exact with your measurments or you can go more or less. I tend to do everything by eye as I know what I like but if you're having problems then the best way is to weigh, time and measure. Have you got a shot glass? This is the best way to control your output as you pour as it is a visible marker. You could of course just mark off a normal glass/cup. Then, I would measure 9g for a single and 16 for a double basket. It is correct that it takes 5-9 seconds for the first coffee to appear. I'd also time 23-25 seconds for a single and 27-28 for a double. Remember to use a slightly finer grind for a single. Once you do this a few times, you'll just do it naturally.


Thanks. I've been using a clear shot-glass for the single shots so I can see how the shot is pouring/developing. I've found this difficult to get right with a single shot though have never tried with a double shot into the clear shot-glass. I've tended to pour into a slightly bigger cup so... I shall try the shot-glass for the double shot and see if that gives me a better clue to what is happening.

cheers


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