# Hit and miss



## standard issue (Jan 10, 2010)

Having recently upgraded from a broken DeLonghi to a Gaggia Baby Class (instantly getting better espresso!) - I am beginning to become somewhat routine about my process:


Purge the grouphead

Measure out the coffee as the purging is going on (don't have a grinder yet)

Tamp the coffee (now with my new Motta tamper)

Knock off the water purge

Slam the porta-filter in (barista style)

Water back on

Shot glasses under

Stand back in amazement!


Sometimes, I get such a thick luscious créma I have to eat it with a spoon, but other times I get a watery mess that fills the shot glasses in 3-5 seconds.

I am using the same coffee, same PF basket, same technique, I've tried the kitchen scales to get the tamp pressure right, still real hit and miss.

When it's good it's better than anything I've paid for in a shop (obviously as I did it) but when it's bad, it's...well...worse than cheap instant!!!

Any advice

Using:


Gaggia Baby Class

Lavazza espresso coffee (I will get a grinder when I have the money)

Fresh water

58mm tamper

Same technique


Thanks


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## standard issue (Jan 10, 2010)

Just pulled a brilliant Americano, the créma is so thick it looks like a giant espresso!

25-27 sec extraction, mouse tails etc, etc.

I did lots of "tamper-twizzling" (polishing) but whilst applying pressure this time, would that make any difference?


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## BanishInstant (Oct 12, 2009)

You mentioned scales and measuring of coffee. Is this a constant amount/weight?

How long do you warm up the machine for?

Do you warm up your glasses/cups?


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## DavidS (Apr 8, 2010)

Sounds like channeling. Avoid tapping and make sure the puck is as level as possible, and the ground coffee is evenly distributed.


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## Glenn (Jun 14, 2008)

Purging the grouphead should take no mroe than a second or two, even on a domestic machine.

One issue could be water temperature stability. Let the machine warm up and then a 2-3 second flush is adequate

Another could be chanelling (make sure you dose (using the same amount of coffee each time) then level and tamp.

Try to keep an even distance from the top of the basket the entire way round) to the tamped coffee grounds.

Try and keep the tamping to 1 motion, staggered tamping pressure can lead to layers building up and the water can find its way into these layers, bypassing other coffee grounds on its way to the bottom of the basket.

Polishing whilst under pressure may cause slight disturbance to the puck.

Do you flip your portafilter upside down after you have tamped? If you tamp too light the grounds will fall out.


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## chrisweaver_barista (Jun 14, 2008)

I'm surprised I'm the first guy to say it. But with espresso, your crema is REALLY going to suffer with pre-ground beans. After beans are ground you're gonna see a drop in crema after about 2-3 minutes, let alone after the 3-4+ days to get it into your machine at home. You don't need to drop a large amount of money to get a good grinder. You can pick up a Hario Skerton hand grinder for

Secondly, look to cut out as many variables as possible. Exactly the same amount of ground coffee each time (if you have scales, think between 18-20 grams, but when you get a dose, stick to it). Simplify your tamp as much as possible. I've seen people pull FANTASTIC shots with one simple heavy tamp followed by a quick polish (lightly turn the portafilter 90 degrees). No tapping.

If you're seeing really fast pours, you won't get good crema, and a lot of issue will be with the pre-ground. The only way to slow the pour, without adjusting the grind, is dosing more ground coffee.


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