# Channeling with my new machine



## bronc (Dec 10, 2012)

I finally got a naked portafilter for my TS. I was having some doubts of channeling because when I was using the normal portafilter with the spouts removed I could see that the coffee wasn't flowing straight down. What I'm seeing with the naked pf is that while the pour is centered there are small jets/squirts of coffee going in different directions (similar to this: http://ineedcoffee.com/wp-content/uploads/2011/09/espresso-spurter-blonding2.jpg) and the flow of the main pour isn't constant - sometimes it speeds up which 'distorts' its shape/form.

In the cup I'm not getting consistent results. I had two shots where I could taste floral notes (as per Rave's tasting notes for the coffee I'm using) but everything else has been a mix of bitter and sour.

Shots are 15g in -> 27-30g out in 27-30sec. The coffee is Brazil Santa Rosalia. I'm using Espresso Parts' HQ 15g basket and I've set the OPV to 10 bar static pressure.

I used the same basket with the Silvia and haven't had such problems. Well, once in a while I would get a shot that was all over the place but most of them were running fine.


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## coffeechap (Apr 5, 2012)

are you following the HX flushing regime, as it appears a mix of temperature in your shots! spritzing is caused by poor portafilter prep.


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## bronc (Dec 10, 2012)

I'm flushing about 100ml of water, waiting for 5-10 sec and extracting. I'm still learning to judge by the look of the water that's coming out of the grouphead. From what I've seen on YT videos, the TS is hardly reaching the temperatures of an E61 machine - I'm not getting loads of steam. I might do a video because it's hard to describe it with words. I'm in the process of sourcing parts for a DIY scace thermofilter device so I can accurately measure the temperature of the water.

It's not that some shots are sour and others bitter but more like bitter and sour at the same time with the bitterness being more of a lingering taste and the sourness being the overwhelming taste. I'm guessing this is caused by a mix of over/underxtraction and too low/high temperature.

My portafilter prep hasn't changed from what it was with the Silvia so I don't know why the difference. Both machines have Ulka pumps, both are set at pretty much the same pressure, and with both I'm using the same basket. It looks like the Silvia was more forgiving of my technique but why..? I might fire her up to do a side by side comparison.


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## 4085 (Nov 23, 2012)

The TS has a thermostat cartridge in the group. When I had mine, no cooling shot was needed. If anything the flush was to increase the temp. As suggested, it is more likely shot prep especially distribution


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## jeebsy (May 5, 2013)

coffeechap said:


> are you following the HX flushing regime, as it appears a mix of temperature in your shots!


How can you tell that?


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## coffeechap (Apr 5, 2012)

jeebsy said:


> How can you tell that?


it was an inference drawn from the mix of biter and sour shots (which can be attributed to temperature differences)


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## bronc (Dec 10, 2012)

I'll post a video tomorrow morning as it's 7pm here.. a bit late for yet another coffee.


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## bronc (Dec 10, 2012)

Did a few tests with my TM902C thermometer. I wedged the thermocouple tip between the grouphead screen and the bolt that holds it in place.

With the machine idling for 40-45 minutes the temperature of the water that exits the grouphead is around 98-99*C. My usual flush (120-140ml) brings down the temperature to about 90*C. After 25-30 sec which is what I usually wait the temperature still hasn't recovered and is at about 90-92*C. If I give it a minute and a half after the long flush the water is at 95*C which would be perfect. After 5 minutes the temperature is again 98-99*C. If I give it a short flush (about a 60-80m) and kill the water, give it a few seconds during which I would usually lock in the portafilter, the temperature is 95-96*C which is good. This leaves me with two options - do a long flush (120-140ml) before grinding, tamping etc. or a quick flush after I've done the shot prep. All of these tests were performed with the 98*C grouphead thermostat. I'm guessing things would be different with the 103*C - faster recovery but requiring a longer flush. It would be better if I could simulate the extraction of a shot (40-50ml in 30 sec which includes the saturation of the grinds) but this will be helpful as well.

Here is a video of the extraction following my newly adopted 'surfing' routine. 15g in, 28g out, 27s. Shot prep: grind directly into portafilter, tap it on the countertop to level, tamp as evenly as I can. The sourness is gone and while the bitterness is less strong than before, it is still present in an unpleasant way. This makes me think that the sourness was due to the temperature (too low as I was flushing too much/not waiting enough) and the bitterness is due to the extraction.


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## Mrboots2u (May 10, 2013)

I would agree with your diagnosis too. Flush less


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## 4085 (Nov 23, 2012)

bronc, I have told you already, there is a sensor which you can buy variable heat settings of which virtually eliminates the need to flush, HX or not. If anything, you flush to increase


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## bronc (Dec 10, 2012)

I know that there is a heating element in the group but at least according to my TC (I've calibrated it with boiling water) there is still a need for a short flush. I will try a shot without any flush though. What is this variable heat setting you're referring to? Do you mean swapping the thermostats controlling the grouphead element?

Any tips on improving the extraction? There are a few dead spots and some spritzing you can see in the video.


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## bronc (Dec 10, 2012)

Just an update. The problem was in the beans (Brazil Santa Rosalia from Rave) or maybe the combination of the beans and my grinder. I bought a bag from a local roaster and I'm getting perfect pours every time. Taste-wise it's also much better altough I suspect that the beans aren't very good because they are quite bland. I also tried a Clever brew and got the same balanced but bland taste. I'm waiting for a kilo of Foundry's Rocko so I'll report back.


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## glevum (Apr 4, 2013)

I also got channelling & mega spitzzing with Raves santa rosalia bean no matter how well i prepped the basket


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## Mrboots2u (May 10, 2013)

Out of interest , what would it be about one bean that would , as people propose on here , make it inherently harder to prep or more inclined to channel? @Gary**** any suggestions ?


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## mremanxx (Dec 30, 2014)

Mrboots2u said:


> Out of interest , what would it be about one bean that would , as people propose on here , make it inherently harder to prep or more inclined to channel? @Gary**** any suggestions ?


Was just wondering the same thing myself, wondered if it the roast was dark that you were grinder coarser or something like that.


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## bronc (Dec 10, 2012)

What I noticed with this particular bean is that when ground to pour at my desired extraction ratio it took less space in the basket than I'm used to. So if 15g of an 'ordinary' (i.e. not this one) bean takes about 3/4 of the basket before tamped, the santa rosalia was more like 1/2 or less. I kept returning to the scales to check if I was dosing the correct amount and it always was within 0.5g of the target. I'm not sure how this is relevant but this particular thing stood out for me. @garydyke1


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## garydyke1 (Mar 9, 2011)

Mrboots2u said:


> Out of interest , what would it be about one bean that would , as people propose on here , make it inherently harder to prep or more inclined to channel? @Gary**** any suggestions ?


Maybe if the roast meant the beans were not soluble enough ? (might still look 'ok')


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## jeebsy (May 5, 2013)

Mrboots2u said:


> Out of interest , what would it be about one bean that would , as people propose on here , make it inherently harder to prep or more inclined to channel? @Gary**** any suggestions ?


A couple of Caravan beans i had were really tricky, even the shop i got them from said they found them difficult to work with


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