I'm getting a lot of channelling with pretty much every shot on my Valexia. Four out of five are sinkers. With my Decent DE1XL I have very little channelling. Perhaps one out of twenty are sinkers. Same beans, different grind size of course. Same puck prep, or as near as damn it. I've changed to an IMS shower screen on the Izzo and tried IMS baskets too. I've done the 5 cent test to ensure optimal puck height. All to no effect. I shot a video of the pre infusion stage of each machine but I can't seem to upload it. So I took a couple of screen shots which show the difference. [URL=https://i.imgur.com/KMLUzgV.jpg][IMG]https://i.imgur.com/KMLUzgV.jpg[/IMG][/URL] [URL=https://i.imgur.com/RQMH62K.jpg][IMG]https://i.imgur.com/RQMH62K.jpg[/IMG][/URL] What do you think? Is the gushing, hotter\* water on the Izzo a possible cause of the channelling? \* As measured by a quality German food probe: 94c coming out of the Izzo and 85c from the Decent. Bear in mind that this is not the temperature in the boiler or inside the group head but rather the water coming out of the group head

@"tompoland"#p789 It’s a drizzle vs a down-pour and is nothing to do with how hot the water is ! The cup will decide if you like the 94C shot. 😀 It also sports the LSM group, is it not ? You now know what happens when you cock the lever; I guess it’s a 1.5-2.0 bar pressure. If you release the lever, if the grind is good, you may be getting > 10 bar pressure. Both are sufficient to guide the water to the path of least resistance. I’m afraid it’s your puck preparation / distribution is the one, which requires a fix. How did the cup taste, unless you literally sink them? Edit 1: 94C seems a little on the higher side unless you are using light roasts. 2: What’s your dosage please? What basket is that ? if you are dosing too little say, 14g-15g on a standard double double or the stock, this is another variable, which you want to address.

@"tompoland"#p789 Rotary pumps, can really push out the water. this dumps a lot of water and pressure on the puck rapidly, whereas the decent does not. This will encourage channeling, **especially, if the same grind level is being used between any two machines of different initial flow characteristics.** This is because the rapid onset of pressure compresses the puck, before the water has soaked it, and it cant resist it. It chokes slightly and then fractures. In my experience, I have never had channelling issues related to higher temperatures, unless the same grind is being used, because the higher temperature seems to more rapidly and completely swell the puck earlier on, and again it chokes slightly, then fractures. I have a machine at the moment that is a profiling machine, but it has snap changes of pressure, as it does the larger one of these early on, there is a large risk of a small puck fracture that is self healing once the pressure is applied for a bit. I tried to reduce it (which worked a bit), in ramping up to the higher pressure in 3 discreet smaller steps. Translating this to the Valexia lever which you have….and a reference to the pump choice in the Evo. Traditional levers have quite a good flow of water from the single boiler held at 123C or whatever you have it set to. the pressure may not be high, but the volume of water that can be pushed per second is. With the Evo it was important to fill the group quickly enough, but not to try and use a pump that would fill it as quickly as a boiler…in both cases the pressure wouldn't be high. The main difference is the Evo pump takes 4s or so to fill the puck and the Izzo will be somewhat faster. This being the case, there may be less preinfusion time when you lower the lever (because your group fills rapidly.) * You could try loosening the grind a little for the Valexia, see if that helps. * Increasing the preinfusion time * combination of both P.S. Theres not much you can do about the temperature without affecting steaming and/or having a larger temperature reduction during the shot because the group is deigned to cool the water on that machine.

Thanks, i have tried a bplus but unfortunately it made no difference. I have also tried filter papers.

Many thanks to all contributors. In no particular order: 1. I have used a Bplus but it has made no difference. Ditto for paper filters. 2. It may be puck prep. I've had consistent shots from previous machines that have come and gone this year including BDB, Technika, Synchronika and of course the Decent. Of course different machines treat the puck in different ways but if it is puck prep, I'd love it for someone to tell me what I'm doing wrong on the Izzo that has worked so well on the E61 machines. 3. It may be grind size. I have measured over 100 shots between the Decent and the Izzo and for the same ratio of 18 grams in and 36 out, I add 8 clicks to the EG-1 for the Izzo over the Decent. In other words the grind size for the Izzo is significantly coarser. Maybe it's too coarse? But then, I am down to a ristretto instead of an espresso. 4. Yes it's the LSM spring lever system. 5. These machines have legions of dedicated followers so it's not the machine (assuming it is functioning as it is meant to). It therefore must be the tool that inserts portafilter into the group head. 😆 6. I've used almost exclusively dark roasts and used the same beans and batch in dialling in the two machines. So introduction of multiple variables simultaneously has been avoided for the most part. 7. Dosage for the Izzo was initially 18g in a 22g basket. Following the five cent test that was increased to 20g in the same basket. 8. I've played with pre-infusion times from 10 seconds to 30 seconds. Seems like a similar result. 9. I only drink espresso so I'm not concerned about steam temperature. I'll play around and keep you posted. I'll try coarser grind size, finer grind sizes but I'll stick to the 5 cent test.

Izzo Valexia channelling

DenisS

Get yourself a bplus or a chinese cheaper copy of that. This will solve all your problems with channeling.

The water flow is too strong during preinfusion and makes it’s way into weaker spots into the puck, creating problems.

LMSC

DenisS The only problem with the screen, IMHO, is the extraction going to extremes resulting in an unpleasant cup especially if the beans are anything other than light or medium light. May be, it’s just me and/or those who think otherwise.

IMO, I don’t think the screen is the solution if the issue can be addressed by focusing on the grind, puck preparation and distribution. 😊

DenisS

Dont know how you do it but I have no such thing. My bplus is 55mm sized and my ims basket is max 55mm the fit is snug. If you put a 53.5mm into a 55mm basket that is another story.

You cannot address the huge flow a older lever gives you, unless you overdose or something so you dont let the water make holes into the puck.

tompoland

Many thanks to all contributors.

In no particular order:

I have used a Bplus but it has made no difference. Ditto for paper filters.
It may be puck prep. I’ve had consistent shots from previous machines that have come and gone this year including BDB, Technika, Synchronika and of course the Decent. Of course different machines treat the puck in different ways but if it is puck prep, I’d love it for someone to tell me what I’m doing wrong on the Izzo that has worked so well on the E61 machines.
It may be grind size. I have measured over 100 shots between the Decent and the Izzo and for the same ratio of 18 grams in and 36 out, I add 8 clicks to the EG-1 for the Izzo over the Decent. In other words the grind size for the Izzo is significantly coarser. Maybe it’s too coarse? But then, I am down to a ristretto instead of an espresso.
Yes it’s the LSM spring lever system.
These machines have legions of dedicated followers so it’s not the machine (assuming it is functioning as it is meant to). It therefore must be the tool that inserts portafilter into the group head. 😆
I’ve used almost exclusively dark roasts and used the same beans and batch in dialling in the two machines. So introduction of multiple variables simultaneously has been avoided for the most part.
Dosage for the Izzo was initially 18g in a 22g basket. Following the five cent test that was increased to 20g in the same basket.
I’ve played with pre-infusion times from 10 seconds to 30 seconds. Seems like a similar result.
I only drink espresso so I’m not concerned about steam temperature.

I’ll play around and keep you posted. I’ll try coarser grind size, finer grind sizes but I’ll stick to the 5 cent test.

LMSC

tompoland You are in the position of giving than receiving! 😊

However, in your case, the initial fill is faster than the Evo. I still think, a little thought, which you might want to consider is re-tamping.

On our Evo at home, we dose 16g-16.4g on the IMS26 than the standard 18g dose, as we have a convex Torr tamper.

We therefore grind a little finer and tamp harder compared to a gentle tamp with a flat tamper. This helped address any channelling and faster pour issues. But, we seldom time the shot as it is always cut at a 6 bar pressure.

The IMS 32 basket can comfortably take 23g-24g; I typically dose 20g for one cup or 24g to split. These two dosages are ground a little coarser, but always get a gentle tamp.

A quick WDT always precedes tamping.

Paolo5

Hi Tompoland!

Does each shot appear first around the circumference of the basket?

Are you able to post a clip of a typical shot?

tompoland

Good idea Paolo, I will video a shot or two.

No to “donuting” … most pours appear as a mixture of dark patches mixed with light patches mixed with gaps.

LMSC

tompoland You may also want to consider sharing a short clip of your puck preparation as well. 😊

tompoland

LMSC also a great idea, will do.

LMSC

tompoland

Dave discussed puck fracture at length. You may want to examine the puck for a fracture and dark patches. 😊

tompoland

Update: I never got around to producing a video like I said I would so apologies for that. In the interim I seem to have solved the problem.

Out of impatience I did something that was rather naughty which was to change two variables at the same time: I dropped the temperature by 5 degrees and used the magic tumbler that was collecting dust (Weber Workshops variety).

This produced a much more even pour consistently over three shots.

Then, based on the lack of volume from pre-infusion and even though the grind size was a full 10 points coarser on the EG-1 than I grind for the Decent, I increased the grind size another 4 points on the EG-1 (thanks to @DavecUK for emphasising this) and the pour was more even again, over another three shots.

Thanks to EVERYONE who contributed suggestions. This was a team effort and I’m grateful for your every contribution.

I can now enjoy the shots from my Izzo again (I really love using the lever).

As a foot note, Santa is delivering a Streitman CT2 to my Queensland Australia address today, exactly seven days after it was shipped from the Netherlands. It will sit next to the Valexia and thus the gauntlet will be thrown down.

One more footnote: I ordered green beans from Melbourne the day before the Streitman shipped via DHL from the Netherlands and according to the tracking app the beans are still sitting in Melbourne 😆.

And I promise this is my last footnote: my condolences to all English cricket fans 😁

LMSC

tompoland condolences to all English cricket fans 😁

Giphy -

Giphy - Emo Reaction GIF by MOODMAN

DavecUK

Looking forward to seeing the Streitman in action.