Packing troubles lead to channeling

[Bliss]

Hi,

Since a few weeks I'm the proud owner of a Isomac Tea. Even though I'm really happy with this machine, I'm experiencing some problems with packing the portafilter. Previously I used an Isomac Giada and never had any problem. If I now inspect the pack after the shot, it's a little wet and I spot some channels in it. The espresso doesn't taste bad or anything, but I suppose it could even taste better.
I've already tried numerous things to prevent it, but it doesn't seem to help. I try to evenly distribute the ground coffee in the PF, but this is hard because when using approx 7 grams of coffee, it doesn't stand above the edge of the PF, so is a little hard to evenly distribute. So I try it using the tamper and softly tapping the sides of the PF. Following I tamp the coffee as level as possible, tap the sides again and tamp again.

As far as my knowledge goes, I'm not doing anything wrong. Does anybody have some ideas or tips to get me going again. It would be highly appreciated.

[skyryders90]

I've already tried numerous things to prevent it, but it doesn't seem to help. I try to evenly distribute the ground coffee in the PF, but this is hard because when using approx 7 grams of coffee, it doesn't stand above the edge of the PF, so is a little hard to evenly distribute. So I try it using the tamper and softly tapping the sides of the PF. Following I tamp the coffee as level as possible, tap the sides again and tamp again.

Since you're using 7 grams, I assume you're making singles and using the single basket? Why 7 grams? Most on here would advocate dosing by volume, not weight, so you dose until you had a nice heaping pile (which WOULD stand above the edge), distribute, then tamp. Do you have the same problem when making doubles?

For me, I find that most issues I think are tamp-related are really dose/distribution-related - tamping is pretty easy, while those other 2 variables are tough for me to nail down in a truly consistent manner.

Also, try tamping and NOT tapping the side - this can tend to introduce channeling problems by disrupting the side seal. There are lots of people on both side of this one, but since you're tapping a having troubles, it might be worth a try to leave the tap out.

[HB]

Most on here would advocate dosing by volume, not weight, so you dose until you had a nice heaping pile (which WOULD stand above the edge), distribute, then tamp.

At one time I would economize on coffee by carefully weighing out each dose. Nowadays I accept the waste that comes with dosing by volume, probably about two grams per double, and gain some time and improved consistency of the distribution. To keep the weights consistent, coffee that's outside its prime goes to practice every few weeks a la Exercises for tuning your barista techniques. The article Perfecting the Naked Extraction is a good place to start for how-to instructions and solutions to common problems.

PS: I have a handful of unused single baskets, if anyone wants to buy them on the cheap.

[another_jim]

Hi,

Since a few weeks I'm the proud owner of a Isomac Tea...

I try to evenly distribute the ground coffee in the PF, but this is hard because when using approx 7 grams of coffee, it doesn't stand above the edge of the PF, so is a little hard to evenly distribute. ...

As far as my knowledge goes, I'm not doing anything wrong. Does anybody have some ideas or tips to get me going again. It would be highly appreciated.

You aren't doing anything wrong.

The single basket that comes with the Tea impossible to dose with 7 grams, this will leave too much headroom and the puck will dissolve in the preinfusion. You will need 9 to 10 grams for this basket. There is a Faema "6 gram" basket which can be used for 7 to 8 grams. Coffeeparts.com in Australia is a source, and will ship. I'm sure there's vendors in Europe, but I do not know them. Perhaps the place you bought your Tea can get it. In any case, until you have the smaller basket (also the "12 gram" double for 14 gram shots), you'll need to dose a minimum of 9 or 10 for the single, and 17 to 19 for the double. Alternatively, you can use other brands' baskets: the Nouva Simonelli and Rancilio baskets are the orthodox size; the Cimbali and LM baskets are as large as the Faema ones.