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Thread: Not looking good naked

  1. #1
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    Not looking good naked

    Gok Wan says: not okay...

    I'd like some help.

    My lovely new Alex Leva came with a naked portafilter, from which I am always seeing the same problem with my extraction. I assume of course that the same thing happens with mt double spout pf. Shots look/ taste the same in the cup. Ie good but could be much better.

    I'll try to describe what I'm experiencing:

    grind 21 grams ; smooth off with finger; tamp with slightly too small stock tamper (nsew) ; pre infuse for about 5 - 7 seconds ; release lever; then

    lets call part of basket nearest machine front 12 o'clock- nearest me 6 o'clock. Extraction comes from 10 11 o'clock and spreads from there, but 8 times out of 10 a steady stream . At 4- 5 o'clock half way to the centre of the basket, NOTHING comes though . I get maybe 1 or 2 lovely dark drops as the rest of the shot is finishing.

    So this is some sort of channelling. Hammering 10 o'clock , but getting nothing out of 5 o'clock.

    Always the same...
    I'm getting a nice fitted tamper in a week or two. Too simple to say that'll fix it?


    I think it must be something habitual, as it always seems to occur in he sme way. I suppose its good that I can get consistency. I'm hoping its just a little technical tweak required.

    id love your advice. Thanks.

    SBM
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  2. #2
    Senior Member gonzo89's Avatar
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    Hey mate,

    Although there will always be someone to criticise what I'm about to say, WDT method with a needle or toothpick takes care of that.

    It's a step that in the past seemed unnecessary to me, but in the end that depends on what the grinder throws at you or the age of the beans themselves. It's the only way I could get shots to behave on my r58 paired with a Major. Previously with my bezzera galatea, no issues at all getting a pretty shot. The way I see it, it's only a few seconds more to add into the equation in order to drink a shot that extracts just as it should. Why bother to make shots if they aren't the best right?

    Cheers
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  3. #3
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    Right.

    I'd wondered if distribution might be the factor in this.
    I'll report back after trying in the morning.

    Thanks for the tip!

    actually, now I think of it. The hg one people recommend wdt. But I forgot about it coz it didn't seem to make much of a difference on my old machine.
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  4. #4
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    What can I say?

    It worked.

    Thanks Gonzo!
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  5. #5
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    Hi, Just saw your post
    Its really humid where I live and I get a bit of clumping
    I use an orphan espresso ipanema dosing funnel and tiny whisk - works really well, I get get even extractions
    Hope that helps
    Dave
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  6. #6
    Senior Member readeral's Avatar
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    Do you swipe off holding the portafilter in your left hand, swiping with your right hand left-to-right? Cause maybe it's not quite left-to-right but offset (for the 10 o'clock problem) and always ends up with more coffee density to the right side (where pushing across will inevitably pack more grinds into the same space, causing your uneven extractions there).

    WDT will solve your problems, without a doubt. You also have other distribution method options as well. WDT is just as valid as other options, but has the benefit of breaking up small clumps. I personally don't care about clumps, so don't WDT. The down side is it takes time - but at home, time doesn't matter as much as good espresso.

    It's just my opinion, but I'm not convinced that NSEW is a necessary or particularly helpful tamping technique. Again, takes time, but also would slide your puck against the opposing wall, potentially impacting adhesion. You seem to be doing just fine with it, so if you're happy, keep to your process
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  7. #7
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    Thanks Dave & Readeral.

    My success rate with wdt is 1/1 attempt. It wasn't perfect, but has effectively solved my problem. Just to practise it now.

    Yes. I was holding it in my right and swiping in a sort of circle. Must have been pushing it to "5 o'clock" . Also, I'm sure my nsew was shifting the puck. Certainly sometimes. But if I didn't do it I had an untamped bit around the edge.

    Looking forward to a custom tamper (when the money box is full!)

  8. #8
    Mal Dimal's Avatar
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    You could also try the so-called "Nutating Tamp" instead of adding in the extra step of whisking or WDT'ing - Takes about two seconds at most and becomes part of your normal tamping technique...

    Mal.
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  9. #9
    Senior Member readeral's Avatar
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    Not looking good naked

    That's what he means by NSEW Mal (or that's how I interpreted it)

    If you mean moving the tamper, apologies! Ignore my earlier comments!

  10. #10
    Mal Dimal's Avatar
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    No mate, two different things entirely.
    NSEW tamps are actually four separate tamps (at least) following the compass rose.

    Nutation is quite different, as described here... https://en.wikipedia.org/wiki/Nutation

    Mal.

  11. #11
    Senior Member readeral's Avatar
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    Yeah so I know what nutation is. Was surprised NSEW was a defined thing! Learn something new every day. I'm personally not so keen on nutation (read nutation into my comments above, rather than NSEW) but it's definitely up for debate, and some will swear by it. Experimentation is key.

    For me, it can be easy to fix something on the surface with an added practice, but where it's cancelling out a bad practice (say delaying the placement of a cup due to side channeling at the beginning of a shot) - I'd be inclined to say "dig deeper and find the root practice causing you grief".
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  12. #12
    Mal Dimal's Avatar
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    Having been using a Nutating Tamp for going on 15 years mate. Over that time, I could count the unsatisfactory shots I've poured on one hand...

    Each to their own of course but don't knock something unless you've given it a good try yourself, I always say...

    Mal.

  13. #13
    Senior Member readeral's Avatar
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    Yeah so my experience has been the opposite, it was something I did for the first few months of making coffee. It's so situational though, my machine is different to yours is different to SBMs. I found more success with a firm squared down tamp, but my tamper is curved, so might have an impact there. Machines and tools.

    I guess - I'm reacting to a situation where many of the pieces of advice received are not always tested _as a matter of course_ - and would always make me inclined to posit counter-arguments to community sanctioned (and entirely legitimate) approaches. Just to help people question their assumptions.

    All part of being in the community.
    That being said - if NSEW is all SBM has attempted thus far - he _should_ try nutation! Might be a good help.
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  14. #14
    Senior Member Yelta's Avatar
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    Very much inclined to agree with Readeral on this one, I've certainly heard of the various techniques mentioned, however there must as he says be an underlying reason for the problem, you would think there would be a simple and straight forward solution.

    At the risk of being thought simple minded, there are only a few variables to work through, shower screen, grind, dose, tamp and basket, the answer must be there somewhere without having to resort to whisking etc.

    Can understand Shortblackmans frustration, we all want to get a new machine performing at it's best ASAP, good luck with your quest.

  15. #15
    Mal Dimal's Avatar
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    Over the 15 years, I've owned 5-6 different machines and have always used the nutating tamp, so it's not machine specific, it's just what I and a lot of others do. It just saves on the need for a separate distribution step since it just becomes part of the normal tamp technique. It's not hiding a fault with my technique or I'm sure that this would eventually show itself. It's nothing more, or less than a distribution method.

    For those people who don't need a distribution step in their routine anywhere, then that's great but I have found right from the beginning, that better distribution equals better results in the cup so I'm not going to change after 15 years of success... I'm an old dog I guess...

    Mal.
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  16. #16
    Senior Member Yelta's Avatar
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    Quote Originally Posted by Dimal View Post
    Over the 15 years, I've owned 5-6 different machines and have always used the nutating tamp, so it's not machine specific, it's just what I and a lot of others do. It just saves on the need for a separate distribution step since it just becomes part of the normal tamp technique. It's not hiding a fault with my technique or I'm sure that this would eventually show itself. It's nothing more, or less than a distribution method.

    For those people who don't need a distribution step in their routine anywhere, then that's great but I have found right from the beginning, that better distribution equals better results in the cup so I'm not going to change after 15 years of success... I'm an old dog I guess...

    Mal.
    If it ain't broke don't fix it.

  17. #17
    Senior Member readeral's Avatar
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    Absolutely! You're welcome to your process. Not trying to win you over to a change, Mal.

    I have a different distribution technique (bumping the side of my portafilter quickly 4 times, from 12 o'clock round to 3 o'clock) which is no more legitimate than another's. However, you might have an opinion on it too

  18. #18
    Senior Member gonzo89's Avatar
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    Quote Originally Posted by shortblackman View Post
    What can I say?

    It worked.

    Thanks Gonzo!
    Very happy to hear it worked
    To add to Mal's suggestion, I also use a nutating tamp. You do have to make sure you aren't getting a slant though if you do use the nutating method. Seems excessive but hey, I can't help it if I like a pretty looking shot. Here in Brisbane it's been clumpy grind madness for months with the humidity levels. That's another reason for my apparant excessive routine.

    Keep up the good shots
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  19. #19
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    Okay. I'm really pleased with this discussion. Thanks for your contributions. I understand nutating and nsew to be different things, and although I feel that I've gone somewhere good with wdt today, I'm now willing to give nutation a go.

    Limited by the amount of coffee experiments my system can handle in one day!

    if I didn't have a naked pf, I would not have had any idea how or where I was not extracting fully. But with it, I can see the under & over extraction coming out in different parts of the same shot.

    Its not that I didn't like my coffee, but I could/ can easily see where improvement can come from, get more out of the beans & gear...
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  20. #20
    Senior Member Yelta's Avatar
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    Quote Originally Posted by readeral View Post
    I have a different distribution technique (bumping the side of my portafilter quickly 4 times, from 12 o'clock round to 3 o'clock) which is no more legitimate than another's. However, you might have an opinion on it too
    Interesting, I use a similar technique, after dosing, tap the PF on the bench a couple of times to settle the dose, then using the top of my tamper (Delrin insert) tap the sides of the PF where needed to distribute the coffee evenly, then tamp, its a quick process, takes longer to describe than do.

    Never really thought of it as a distribution technique, although it obviously is, as others have commented re their method, works for me.

  21. #21
    Senior Member simonsk8r's Avatar
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    Would like to bump this thread up haha, as I'd love to get clarification on this, specifically how distribution technique can affect this. I'm struggling in finding a decent, repeatable distribution technique, mine now doesn't seem to be getting consistent pours.

    Keep getting a dead spot in the centre of a bottomless portafilter extraction, it sometimes eventually comes together quickly, but sometimes it comes at 18s or even 24s into a pour when nothing has changed in distribution...

    My current distribution is dose until 3/4 full, vertical collapse. When full do some horizontal taps to hopefully even out the coffee in the lower and upper parts of the pile, vertical collapse, stockfleth and tamp. Sometimes this works well, sometimes it doesn't. Coming to more central earlier in the pour at times, and multiple streams for most of the pour at others.

    Something I'd love to chat about is if clumping affects distribution at all? If there's more clumping at one grindup, the horizontal taps may not really allow proper evening out/movement of the grounds, because the big clumps might be in the way and don't move around that easily...

    And does it MATTER if it comes central I wonder? Makes sense that it would be a more even extraction if it came central rather than multiple streams...

    Again, am just trying to determine a consistent distribution method with my newish machine and new grinder. Seems that everyone has something that works well for them, just wondering if clumping does indeed change how one should distribute, due to those clumps not really moving around to distribute properly/blocking other grounds from moving.

    Thanks y'all!

    *Edit: and yes, I plan on trying out a whole bunch, am not just here to theorise about it. But would be great to get different perspectives on pros and cons of each (or just what you use), and what distribution styles are good/not good for what situations, e.g. clumping

  22. #22
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    Not looking good naked

    Hi I used to get this problem on my Cremina, it's called donut channeling. I solved it by tamping with a good fitting flat tamp with very little pressure just enough to get the grinds flat, then give it a light tamp with a small convex tamper to encourage water to flow into the middle. Also after much experimenting and reading on another forum which deals with lever machines more, I've found it's best to not tap your grinds down too much, and I wouldn't be loading grinds twice if you can help it. I do one full dose- it's timed using my Vario and use a OE funnel. Then I tap the PF on the bench very lightly maybe 2-3 times max to collapse grinds. I've found this minimises channeling. Alternatively you can just buy a convex tamper.
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  23. #23
    Senior Member simonsk8r's Avatar
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    Quote Originally Posted by Wynton87 View Post
    Hi I used to get this problem on my Cremina, it's called donut channeling. I solved it by tamping with a good fitting flat tamp with very little pressure just enough to get the grinds flat, then give it a light tamp with a small convex tamper to encourage water to flow into the middle. Also after much experimenting and reading on another forum which deals with lever machines more, I've found it's best to not tap your grinds down too much, and I wouldn't be loading grinds twice if you can help it. I do one full dose- it's timed using my Vario and use a OE funnel. Then I tap the PF on the bench very lightly maybe 2-3 times max to collapse grinds. I've found this minimises channeling. Alternatively you can just buy a convex tamper.
    Ah interesting thoughts... especially regarding not tapping grinds too much and loading grinds twice, curious what your reasons are for that? Is it sort of along the lines of if you load half or 3/4 of grinds then collapse, then top up and collapse, that it'll be a different density throughout the basket, as you've collapsed a certain amount, then topped up and collapsed again, so it's all a bit uneven?

    I never collapse too much I don't think, it was only one vertical collapse after 3/4 filling, then top up, horizontal taps, stockfleth, then one final vertical collapse. But there may be something in this process that is causing unevenness/inconsistencies... although I've seen many baristas do that 1/2 or 3/4 collapse... That's why I pondered whether clumping possibly changed how tapping/collapsing affects the total mass of grounds and where they are placed/displaced.

    I do own a convex tamper but never thought too much of them, didn't make sense as it seems it would lead towards an uneven extraction, but interesting what you said, as if one is constantly getting 'donut' extractions it would encourage more water flow in the centre...

    Great stuff, thanks Wynton87!

  24. #24
    Rbn
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    Quote Originally Posted by Dimal View Post
    Over the 15 years, I've owned 5-6 different machines and have always used the nutating tamp, so it's not machine specific, it's just what I and a lot of others do. It just saves on the need for a separate distribution step since it just becomes part of the normal tamp technique. It's not hiding a fault with my technique or I'm sure that this would eventually show itself. It's nothing more, or less than a distribution method.

    For those people who don't need a distribution step in their routine anywhere, then that's great but I have found right from the beginning, that better distribution equals better results in the cup so I'm not going to change after 15 years of success... I'm an old dog I guess...
    Mal.
    What is a nutating tamp? Please

    I am back to getting channelling in my Naked P/F.

    I have lost my touch, was heaps better before and I can't figure what I am doing differently.

    Searched for it found it, I think, rocking the tamper to attemt to get the edges tamped.

    Maybe an alternative to buying the "Big Step" from Pullman.
    But always difficult to get to the "edge".

    I do collapse my basket when grinding into it 2-4 times.
    Last edited by rawill; 3 Weeks Ago at 08:36 AM.

  25. #25
    Senior Member flynnaus's Avatar
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    Quote Originally Posted by rawill View Post
    What is a nutating tamp? Please

    I am back to getting channelling in my Naked P/F.

    I have lost my touch, was heaps better before and I can't figure what I am doing differently.
    As per Mal's post a nutating tamp won't necessarily help if there is a fault in your technique but plenty of info via google, including a youtube vid.
    .
    First things first, what has changed recently that may have contributed to the channeling? Are you using different beans? Also, what sort of grinder do you have and how old are the burrs?
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  26. #26
    Senior Member simonsk8r's Avatar
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    Quote Originally Posted by rawill View Post
    What is a nutating tamp? Please

    I am back to getting channelling in my Naked P/F.

    I have lost my touch, was heaps better before and I can't figure what I am doing differently.

    Searched for it found it, I think, rocking the tamper to attemt to get the edges tamped.

    Maybe an alternative to buying the "Big Step" from Pullman.
    But always difficult to get to the "edge".

    I do collapse my basket when grinding into it 2-4 times.
    A nutating tamp is sort of like a rocking motion in a circular direction. As Mal has described in the past it's not so much like a coin spinning around on it's edge, that would just push the edges down rather than distribute anything, but more like in the rotation it displaced and push the grounds around towards the edges.

    So not a really fast motion like a wobbling coin, but more like a gyroscope as it's starting to lose it's charge/spinning momentum and it starts to do that sideways "I'm drunk" thing (best way I could explain it haha). So it acts to push the grounds AHEAD of the base, so it's a much slower motion than just sorta doing a spin around the edge wobble.

    To me it's not something that 'cheats' your way out of bad technique, but it's a legitimate distribution technique that yes does require practice, but works effectively to fill in gaps. Very true in that you need to make sure all other parameters are in place, if you dose and you have a completely lopsided mound or you're doing too many crazy taps etc then nutation won't fix all that.

    Now I'm not 100% sure if the tamper needs to be slightly undersized for it to work compared to using a precision fitted tamper, maybe Mal can chime in! But I think it makes sense to use a slightly undersized tamper for the nutation, so that it actually pushes the grounds around, a fitted tamper may only just sort of 'skirt' along the edges...

    And to me it's not a tamping technique but a distribution technique, which inevitably will tamp the grounds a little due to the weight of the tamper, but will still require a proper tamp after nutating is done.

    But yeah have a look at everything you're doing at each step, and change something small each time to see the results (keep dose and grind exactly the same though, only change distribution technique). This is pretty much what I'm doing haha, and why I brought this all up, be good to discuss the techniques and pros and cons etc.
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  27. #27
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    Not looking good naked

    Quote Originally Posted by simonsk8r View Post
    Ah interesting thoughts... especially regarding not tapping grinds too much and loading grinds twice, curious what your reasons are for that? Is it sort of along the lines of if you load half or 3/4 of grinds then collapse, then top up and collapse, that it'll be a different density throughout the basket, as you've collapsed a certain amount, then topped up and collapsed again, so it's all a bit uneven?

    I never collapse too much I don't think, it was only one vertical collapse after 3/4 filling, then top up, horizontal taps, stockfleth, then one final vertical collapse. But there may be something in this process that is causing unevenness/inconsistencies... although I've seen many baristas do that 1/2 or 3/4 collapse... That's why I pondered whether clumping possibly changed how tapping/collapsing affects the total mass of grounds and where they are placed/displaced.

    I do own a convex tamper but never thought too much of them, didn't make sense as it seems it would lead towards an uneven extraction, but interesting what you said, as if one is constantly getting 'donut' extractions it would encourage more water flow in the centre...

    Great stuff, thanks Wynton87!
    I can't verify the science behind not dosing twice but my gut feeling is that you want to minimise how much you play with the grinds, I guess keeping them as fluffy and aerated as possible. I've heard a lot of people using lever machines get their best thickest syrupy shots when they hardly tamp, some don't even tamp, they just use the shower screen as a tamp. With that theory in mind I'm guessing tapping or tamping too much can amplify the density of any clumps and lead to channels. This might be unique to lever machines though. Just my experience.

    With regard to seeing baristas do certain things, I guess you have to remember that they will generally have high level grinders that give very fluffy and evenly distributed grinds anyway.

    As for distribution techniques and de-clumping, I don't like the idea because I feel you should get your grinds locked into the machine as quick as possible to maximise taste.

    You should definitely give you convex tamp a go! Report back!

  28. #28
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    Wynton, interested as to why you say declumping/distribution techniques are not a good idea? I often up end the basket into a small macchiato/large shot glass glass (they are a snug fit) to declump and find the grounds 'shrink' in size and noticeably are less clumped together.

    I have seen the WDT before and looks a bit cumbersome, even though many swear by it.

    I would assume the less fluffy grounds the better to reduce the amount of air pockets and potential channels?

  29. #29
    Rbn
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    I will continue to follow, I got a better shot with a nutating style tamp.
    Would have been "perfect" if I hadn't been using a Naked P/F

    Was with a 7gm VST.
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  30. #30
    Mal Dimal's Avatar
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    Now I'm not 100% sure if the tamper needs to be slightly undersized for it to work compared to using a precision fitted tamper, maybe Mal can chime in! But I think it makes sense to use a slightly undersized tamper for the nutation, so that it actually pushes the grounds around, a fitted tamper may only just sort of 'skirt' along the edges...
    Doesn't need to be significantly undersized; 0.5mm clearance is plenty...

    Mal.
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  31. #31
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    Quote Originally Posted by WhatEverBeansNecessary View Post
    Wynton, interested as to why you say declumping/distribution techniques are not a good idea? I often up end the basket into a small macchiato/large shot glass glass (they are a snug fit) to declump and find the grounds 'shrink' in size and noticeably are less clumped together.

    I have seen the WDT before and looks a bit cumbersome, even though many swear by it.

    I would assume the less fluffy grounds the better to reduce the amount of air pockets and potential channels?
    I don't think distribution techniques are bad per se, I'm sure it helps minimise channels but personally I prefer not as I want to minimise time between grinding and extracting as the grinds stale very quickly once ground. Also i can't be bothered and also I'm happy with my extractions with my current technique.

  32. #32
    Senior Member simonsk8r's Avatar
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    Quote Originally Posted by Wynton87 View Post
    I can't verify the science behind not dosing twice but my gut feeling is that you want to minimise how much you play with the grinds, I guess keeping them as fluffy and aerated as possible. I've heard a lot of people using lever machines get their best thickest syrupy shots when they hardly tamp, some don't even tamp, they just use the shower screen as a tamp. With that theory in mind I'm guessing tapping or tamping too much can amplify the density of any clumps and lead to channels. This might be unique to lever machines though. Just my experience.

    With regard to seeing baristas do certain things, I guess you have to remember that they will generally have high level grinders that give very fluffy and evenly distributed grinds anyway.

    As for distribution techniques and de-clumping, I don't like the idea because I feel you should get your grinds locked into the machine as quick as possible to maximise taste.

    You should definitely give you convex tamp a go! Report back!
    Yeah definitely not great to play with the grinds too much, but I think distribution is something pretty vital, and isn't talked about enough, with many other topics taking precedence. Those other topics are important absolutely (roast level, days rest, grinder, temp etc), but distribution (and tamping) is the last step before extraction, and to me matters the most, because it renders all those previous steps almost pointless really. If the actual ground coffee isn't distributed well and therefore isn't extracted properly, then it's a big variable that's being overlooked. But it depends, one may not have to focus as much on distribution due to the grinder and how well it doses and if it produces perfectly fluffy grinds.

    Yeah good point about high-end grinders and not having to worry about adding extra techniques!

    And yeah interesting you say about wanting to get the grinds in as quick as possible, will keep it in mind for sure.
    Quote Originally Posted by WhatEverBeansNecessary View Post
    Wynton, interested as to why you say declumping/distribution techniques are not a good idea? I often up end the basket into a small macchiato/large shot glass glass (they are a snug fit) to declump and find the grounds 'shrink' in size and noticeably are less clumped together.

    I have seen the WDT before and looks a bit cumbersome, even though many swear by it.

    I would assume the less fluffy grounds the better to reduce the amount of air pockets and potential channels?
    Yeah depends on the grinder I'd say. Some dose and even distribute well, not to mention fluffy grinds so no extra steps are necessary.

    WDT doesn't take too much longer than other techniques, I had a play with it today and was a bit slow, but I'm sure it can be sped up, will post results of my distribution experiment I did today soon!
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  33. #33
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    Quote Originally Posted by Wynton87 View Post
    I can't verify the science behind not dosing twice but my gut feeling is that you want to minimise how much you play with the grinds, I guess keeping them as fluffy and aerated as possible. I've heard a lot of people using lever machines get their best thickest syrupy shots when they hardly tamp, some don't even tamp, they just use the shower screen as a tamp. With that theory in mind I'm guessing tapping or tamping too much can amplify the density of any clumps and lead to channels. This might be unique to lever machines though. Just my experience.

    With regard to seeing baristas do certain things, I guess you have to remember that they will generally have high level grinders that give very fluffy and evenly distributed grinds anyway.

    As for distribution techniques and de-clumping, I don't like the idea because I feel you should get your grinds locked into the machine as quick as possible to maximise taste.

    You should definitely give you convex tamp a go! Report back!
    G'day Wynton87

    As you can guess from my handle, I have spent a lot of years playing with tampers. I have quite a collection of concave, flat, US curved convex, Euro curved convex and even a "curved with flat centre" which was called a Scandinavian curve at the time.

    VST do not recommend anything except a flat tamper. Perger has his big step - which is the opposite of convex as it has an "outer ring step" with a flat base. I actually have two RB's - one US, one Euro curve. None of the "non flat" ones work properly in a VST, so to that extent Vince Fedele (VST founder) is correct. The only time a convex tamper has worked for me personally is when the distribution is poor (think clumps and static) or it is overdosed (a "far too common" CS technique it seems). OTOH, every time I find a site with a convex tamper I can improve their coffee using a flat tamp - even when the baskets and the machine is not what I regard as quality.

    I would suggest most CS'r's (i.e. those who do not overdose) stay well away from convex tampers as their Achilles heel is a strong tendency to channel and spray - obvious especially when using a naked p/f. Oh, and the extraction rate usually drops 2 to 3% as well, a sure sign that something is amiss.

    TampIt
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    Interesting ok I'll take that on board tampit, so I should try distribution then. What if that deoesnt work then?

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    I was thinking the same as above, how much coffee are you putting into your basket? If you use a vst or the like they can be particular about volume(changes with the density of the coffee you're using). Also what are your roasts like do you roast you're own coffee or are they from a regular supplier? Using underdeveloped roasts will guarantee difficult pours.

  36. #36
    Senior Member simonsk8r's Avatar
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    Quote Originally Posted by Jono_Willmer View Post
    I was thinking the same as above, how much coffee are you putting into your basket? If you use a vst or the like they can be particular about volume(changes with the density of the coffee you're using). Also what are your roasts like do you roast you're own coffee or are they from a regular supplier? Using underdeveloped roasts will guarantee difficult pours.
    Not sure if you're talking to me or Wynton87, but it's between 20.5g to 22g coffee depending on the bean. Certainly isn't overdosed nor does it seem under, but currently keep getting two streams of coffee that does eveeeeeentually go central haha.. at 18s some times, and 24s others... this was from using WDT too which I've been experimenting with.

    The thing is, the pour is just looking... outstanding after WDT. Even though it doesn't go central until a long time, the colouring is magnificent, and so thick and droopy, taste has varied, but the pour has slowed right down at times so may need to quicken it and try again. May be possible that it's too fine, and it's hard for the pour to come central...

    Then surely ristrettos would never come to a central pour, yet I think I've seen that occur... I'll put that out there too! When pulling a nice slow ristretto in a naked portafilter, does the pour go central? I shall experiment with that too.. really slow flowing shots would have trouble getting through the puck so may not reach a central agreement haha... all just theories anyways.

    Ah yes and the basket I'm using is a IMS/Pesado 20g precision basket, similar to VST i would think. In what way are they particular with the volume that's dosed? As in can't be too down/updosed?

    The roast has varied depending on the bean I'm trying, i haven't done a proper big roast in awhile, but I have used Ethiopia Harrar roasted by Andy, believe I got better pours with that, and currently using a Columbian Excelso bean which is more medium-dark roast, which I'm finding is quite clumpy (whether that's my grinder or the roast in not sure, as I've heard that darker roasts clump more potentially...)

    Edit: recently ordered a cheapo coffee distribution tool on eBay... had to give it a crack! Can't wait to have a play haha
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    Try dosing a bit less or grinding a bit coarser and see what happens...
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    Quote Originally Posted by Wynton87 View Post
    Interesting ok I'll take that on board tampit, so I should try distribution then. What if that deoesnt work then?
    Firstly, I use VSTs exclusively these days. I would hope the IMS is a similar standard to the VST so this may help (I know EQ / HQ "precision baskets" are not). I have been using naked p/f's now for so long I cannot remember the start date reliably - sometime in the early '80's I think. I actually learnt about channeling using a naked (called "bottomless" at the time) in 1979 and after a couple of years my technique was good enough to pick up a consistent flavour advantage using a naked. I do not have any p/fs at home with a spout other than a spare one I don't use anyway from my second La Pav 2 group - it is a bit of a wreck due to severe mistreatment before I purchased it.

    Dosing - I found that VSTs state (and require) a quite narrow dosing range, however I also have found a few machines where the upper end of that range was still impractical / too overdosed. VSTs really need a grind about one third finer than "standard espresso grind" (whatever that means - a moving target anyway).

    Grinding - a number of commercial grinders will not grind well enough / fine enough to get a decent shot out of a VST within its rated dosage. In an extreme moment of curiosity I sieved / filtered their output and when the particle spread was even enough they became "VST friendly". We actually need a major grinder rethink IMO. FWIW, I use two Mahlkonig Varios at home - they work well with VSTs.

    For 15 / 18 /20 /22g baskets I use a pair of fitted & tapered (i.e. the sides are the same slope as the side of the basket) Pullman 316 stainless Barista tampers. One is designed to get within 2mm of the bottom of the basket (pretamper) which I use for a very light tamp (barely more than the tamper weight). When I get anal and / or setting up a new system / roast from scratch I often lightly tamp every two mm of "coffee fluff" progressively. In all cases I use my final tamper for the last tamp - it would reach an absolute maximum of 5mm down into the basket, so I don't get any grounds scattering around inside the basket (I suspect that is a real shot killer, however I am not 100% convinced). Using such tightly fitted tampers with a Vario (no clumps, static or any other grinder snafu - which is why I bought a second one), I do not do any distribution technique at all - it effectively bypasses the need for them.

    Previously I used to do a nutating tamp (just like dimal). Before that I used all the common ones mentioned (Staub, WDT, NSEW and even briefly a "tap p/f hard and then use a convex tamper once @ 30lbs ala Schomer"). BTW, I reckon any tapping after the first tamp is an absolute no-no. These days I only do a distribution technique if I encounter foreign baskets (which do not fit my tampers), a poor grinder (too often), or if I do not have my tampers with me for some reason (unplanned coffee foray).

    Hope this helps


    TampIt
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    Tampit, No P/F with spouts?
    I have been thinking that too, however, what if you use a big triple (4 shot) basket and want to split the shot to make 2 doubles.
    That is why I think I wnat to keep a P/F with a spout.
    Hence, my new SS 6910 P/F will stay with a spout.

    Re the tamper that "doesn't fit", I think the lugs are about 1 mm longer than the later ones. This one was build date Dec 2007 (527), so a little newer than mine that is Sept 2007.
    Doesn't make sense, but there you go, I might take a little off the lugs and see what happens!

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    Quote Originally Posted by simonsk8r View Post
    Not sure if you're talking to me or Wynton87, but it's between 20.5g to 22g coffee depending on the bean. Certainly isn't overdosed nor does it seem under, but currently keep getting two streams of coffee that does eveeeeeentually go central haha.. at 18s some times, and 24s others... this was from using WDT too which I've been experimenting with.

    The thing is, the pour is just looking... outstanding after WDT. Even though it doesn't go central until a long time, the colouring is magnificent, and so thick and droopy, taste has varied, but the pour has slowed right down at times so may need to quicken it and try again. May be possible that it's too fine, and it's hard for the pour to come central...

    Then surely ristrettos would never come to a central pour, yet I think I've seen that occur... I'll put that out there too! When pulling a nice slow ristretto in a naked portafilter, does the pour go central? I shall experiment with that too.. really slow flowing shots would have trouble getting through the puck so may not reach a central agreement haha... all just theories anyways.

    Ah yes and the basket I'm using is a IMS/Pesado 20g precision basket, similar to VST i would think. In what way are they particular with the volume that's dosed? As in can't be too down/updosed?

    The roast has varied depending on the bean I'm trying, i haven't done a proper big roast in awhile, but I have used Ethiopia Harrar roasted by Andy, believe I got better pours with that, and currently using a Columbian Excelso bean which is more medium-dark roast, which I'm finding is quite clumpy (whether that's my grinder or the roast in not sure, as I've heard that darker roasts clump more potentially...)

    Edit: recently ordered a cheapo coffee distribution tool on eBay... had to give it a crack! Can't wait to have a play haha
    I recently bought a roasted coffee that I roast at home to see how it compares and I've struggled to get the pour close to acceptable using my Mythos 1 grinder and it is so frustrating because there is only so much you can do before you realise this coffee is never going to work well. I just end up throwing it out or grinding it for pour over.

    Sounds like you're on the right track, I've found the OCD a help to my routine so I'm sure you'll get good results from the distribution tool you've bought.

    One suggestion I have is try and keep the dose the same each extraction(of the current bean you're using), this will help you dial in your grind better, otherwise you'll only ever reach an average with your grind, you'll see an improvement in taste and over time it will help you to adjust grind settings quickly to taste.
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    Quote Originally Posted by TampIt View Post
    Firstly, I use VSTs exclusively these days. I would hope the IMS is a similar standard to the VST so this may help (I know EQ / HQ "precision baskets" are not). I have been using naked p/f's now for so long I cannot remember the start date reliably - sometime in the early '80's I think. I actually learnt about channeling using a naked (called "bottomless" at the time) in 1979 and after a couple of years my technique was good enough to pick up a consistent flavour advantage using a naked. I do not have any p/fs at home with a spout other than a spare one I don't use anyway from my second La Pav 2 group - it is a bit of a wreck due to severe mistreatment before I purchased it.

    Dosing - I found that VSTs state (and require) a quite narrow dosing range, however I also have found a few machines where the upper end of that range was still impractical / too overdosed. VSTs really need a grind about one third finer than "standard espresso grind" (whatever that means - a moving target anyway).

    Grinding - a number of commercial grinders will not grind well enough / fine enough to get a decent shot out of a VST within its rated dosage. In an extreme moment of curiosity I sieved / filtered their output and when the particle spread was even enough they became "VST friendly". We actually need a major grinder rethink IMO. FWIW, I use two Mahlkonig Varios at home - they work well with VSTs.

    For 15 / 18 /20 /22g baskets I use a pair of fitted & tapered (i.e. the sides are the same slope as the side of the basket) Pullman 316 stainless Barista tampers. One is designed to get within 2mm of the bottom of the basket (pretamper) which I use for a very light tamp (barely more than the tamper weight). When I get anal and / or setting up a new system / roast from scratch I often lightly tamp every two mm of "coffee fluff" progressively. In all cases I use my final tamper for the last tamp - it would reach an absolute maximum of 5mm down into the basket, so I don't get any grounds scattering around inside the basket (I suspect that is a real shot killer, however I am not 100% convinced). Using such tightly fitted tampers with a Vario (no clumps, static or any other grinder snafu - which is why I bought a second one), I do not do any distribution technique at all - it effectively bypasses the need for them.

    Previously I used to do a nutating tamp (just like dimal). Before that I used all the common ones mentioned (Staub, WDT, NSEW and even briefly a "tap p/f hard and then use a convex tamper once @ 30lbs ala Schomer"). BTW, I reckon any tapping after the first tamp is an absolute no-no. These days I only do a distribution technique if I encounter foreign baskets (which do not fit my tampers), a poor grinder (too often), or if I do not have my tampers with me for some reason (unplanned coffee foray).

    Hope this helps


    TampIt
    If I can remove the convex tamp from my routine I'd be pretty stoked. Currently I use a vario and yeh elektra 18gr basket in my Cremina and I does about 16gr into it. I have a custom flat tamper, but if I use that alone I get bad donut channeling. So what are you suggesting I do differently? Given that I can't use VST baskets.

  42. #42
    Senior Member simonsk8r's Avatar
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    Quote Originally Posted by MrJack View Post
    Try dosing a bit less or grinding a bit coarser and see what happens...
    Yeah definitely am going to try that... it's strange.. I wonder if the flow is too slow that things just get more trapped and find it hard to come together in a central pour...
    Quote Originally Posted by TampIt View Post
    Firstly, I use VSTs exclusively these days. I would hope the IMS is a similar standard to the VST so this may help (I know EQ / HQ "precision baskets" are not). I have been using naked p/f's now for so long I cannot remember the start date reliably - sometime in the early '80's I think. I actually learnt about channeling using a naked (called "bottomless" at the time) in 1979 and after a couple of years my technique was good enough to pick up a consistent flavour advantage using a naked. I do not have any p/fs at home with a spout other than a spare one I don't use anyway from my second La Pav 2 group - it is a bit of a wreck due to severe mistreatment before I purchased it.

    Dosing - I found that VSTs state (and require) a quite narrow dosing range, however I also have found a few machines where the upper end of that range was still impractical / too overdosed. VSTs really need a grind about one third finer than "standard espresso grind" (whatever that means - a moving target anyway).

    Grinding - a number of commercial grinders will not grind well enough / fine enough to get a decent shot out of a VST within its rated dosage. In an extreme moment of curiosity I sieved / filtered their output and when the particle spread was even enough they became "VST friendly". We actually need a major grinder rethink IMO. FWIW, I use two Mahlkonig Varios at home - they work well with VSTs.

    For 15 / 18 /20 /22g baskets I use a pair of fitted & tapered (i.e. the sides are the same slope as the side of the basket) Pullman 316 stainless Barista tampers. One is designed to get within 2mm of the bottom of the basket (pretamper) which I use for a very light tamp (barely more than the tamper weight). When I get anal and / or setting up a new system / roast from scratch I often lightly tamp every two mm of "coffee fluff" progressively. In all cases I use my final tamper for the last tamp - it would reach an absolute maximum of 5mm down into the basket, so I don't get any grounds scattering around inside the basket (I suspect that is a real shot killer, however I am not 100% convinced). Using such tightly fitted tampers with a Vario (no clumps, static or any other grinder snafu - which is why I bought a second one), I do not do any distribution technique at all - it effectively bypasses the need for them.

    Previously I used to do a nutating tamp (just like dimal). Before that I used all the common ones mentioned (Staub, WDT, NSEW and even briefly a "tap p/f hard and then use a convex tamper once @ 30lbs ala Schomer"). BTW, I reckon any tapping after the first tamp is an absolute no-no. These days I only do a distribution technique if I encounter foreign baskets (which do not fit my tampers), a poor grinder (too often), or if I do not have my tampers with me for some reason (unplanned coffee foray).

    Hope this helps


    TampIt
    Great post TampIt. I may even try going from the Pesado/IMS basket to the standard one that came with the naked, and see what happens!
    Quote Originally Posted by Jono_Willmer View Post
    I recently bought a roasted coffee that I roast at home to see how it compares and I've struggled to get the pour close to acceptable using my Mythos 1 grinder and it is so frustrating because there is only so much you can do before you realise this coffee is never going to work well. I just end up throwing it out or grinding it for pour over.

    Sounds like you're on the right track, I've found the OCD a help to my routine so I'm sure you'll get good results from the distribution tool you've bought.

    One suggestion I have is try and keep the dose the same each extraction(of the current bean you're using), this will help you dial in your grind better, otherwise you'll only ever reach an average with your grind, you'll see an improvement in taste and over time it will help you to adjust grind settings quickly to taste.
    Yeah for sure, yeah i have been keeping dose very consistent for every shot, but the grinder steps are far too large it seems, so I only can change grind setting if it's a drastic change that needs to happen, otherwise altering dose is what I need to do.

    And yeah very interesting about the roasted beans from elsewhere... I'll keep that in mind, thanks for the input everyone, has been very helpful so far!

  43. #43
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    Quote Originally Posted by rawill View Post
    Tampit, No P/F with spouts?
    I have been thinking that too, however, what if you use a big triple (4 shot) basket and want to split the shot to make 2 doubles.
    That is why I think I wnat to keep a P/F with a spout.
    Hence, my new SS 6910 P/F will stay with a spout.
    G'day again rawill

    Simply divide that 4 shot into two separate 15g shots. Still no spouts needed. I still have an unbranded 28g quad basket, rarely used these days as I usually do two doubles instead.

    The other (elephant in the room) issue is extraction ratio - which is really a measurement of flavour whack, not directly related to taste. Trad baskets (like my 28g) extract at about 16% when optimised for taste, VSTs often get about 23 to 24% with my Vario (about 21% with my EM480). That means my 22g VST actually delivers more flavour out of less coffee than the big quad basket even when I used my 480's (do the math). So we really need about a 10 to 11g VST basket to cover the middle range for some roasts. FWIW, I normally use a 7g single in my naked - given a decent, fresh (however always "post green smell") light to medium SO roast it has plenty of flavour whack and remains some of my best tasting coffee ever. Friends and family agree on that one. Interestingly enough, Jim Schulman has reached a similar conclusion - singles are creamier and sweeter when optimised and have no loss of flavour even as an espresso (well, they do have less volume than a double, however anything above "plenty of flavour" is not relevant).

    Quote Originally Posted by rawill View Post
    Re the tamper that "doesn't fit", I think the lugs are about 1 mm longer than the later ones. This one was build date Dec 2007 (527), so a little newer than mine that is Sept 2007.
    Doesn't make sense, but there you go, I might take a little off the lugs and see what happens!
    You are right, it doesn't make sense - I hope you are meaning a p/f not a tamper...

    I have a new 6900 collar - it has slightly longer "lugholes" so your "find" may be a 6910 with a 6900 p/f. Check it against your other p/fs and grind away if it is longer (from the trailing edge is probably better). If not, please PM me before you attack it. Please provide me with the exact measurements of the ill fitting beast and I will check it against my 6900 collar and 6910 p/fs.

    TampIt
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  44. #44
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    Quote Originally Posted by Wynton87 View Post
    If I can remove the convex tamp from my routine I'd be pretty stoked. Currently I use a vario and yeh elektra 18gr basket in my Cremina and I does about 16gr into it. I have a custom flat tamper, but if I use that alone I get bad donut channeling. So what are you suggesting I do differently? Given that I can't use VST baskets.
    G'day again Wynton87

    As a previous manual lever Electra owner - for 15+ years, I feel your pain. Non VST: that is exactly why I did not replace my Electra (divorce casualty) when I returned to Oz. I also used a friend's Cremina (great engineering, loved it) for a few weeks at one point.

    The only time I managed donut channeling in either manual lever was when the grind was too coarse, dose too low* and/or I was too gungho on the lever pull. Mostly it was grind (or maybe I just learnt by stuffing up a few "over pulled shots"). I cannot recall ever having a distribution issue with either machine when fed by my Major grinder (big flat burr beastie - no match for the Vario at "VST sub espresso grinds", but close at "normal espresso grinds"). Oh, just like all my machines, I did convert the Electra to a naked so the pour impressions are accurate.

    So I would try grinding finer - and your Vario (if it is a gen2 or gen3) is outstanding at finer grinds - and dosing to basket spec by weight.

    TampIt
    dose too low*: I just reread your thread - every time I underdosed the 18g Electra basket the coffee pour went to schlock. I couldn't get 17g to work, so I am 90% certain your 16g would be a fail anyway (donut channeling or not).

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    Try watching some slow motion espresso shots on youtube (you can slow them down further with the video settings). Even for shots that look very even at normal speed, the espresso almost always appears at the outer edge of the basket first when you see it in slow motion.

    I have a few ideas as to why this happens in espresso pours (relating in part to basket shape and grinds distribution). It is consistent with studies of flow in other kinds of packed beds, which typically show higher velocity flow at the perimeter and mostly uniform velocity everywhere else (unlike laminar flow in a pipe, which is fastest in the centre).

    In my experience it is exacerbated in very tight pours - so I would expect grinding finer, over-dosing and very firm tamping would make this worse. Slower flow is the result of greater resistance (also caused by those three factors), hence the correlation between the two.

    The flow outside of the basket is dominated by the competing effects of gravity, viscosity and surface tension. If there is not sufficient (or any) flow through the centre of the puck (relative to at the perimeter), then the stream won't come together in the centre.


    Edit: Here is one I prepared earlier...
    Last edited by MrJack; 2 Weeks Ago at 03:27 PM. Reason: Added video.
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    Senior Member Yelta's Avatar
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    Now for something completely different, still naked

    https://www.youtube.com/watch?v=OOgd9hitEAE
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    Quote Originally Posted by MrJack View Post
    Edit: Here is one I prepared earlier...
    Looks delicious!!

    Cheers

  48. #48
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    Quote Originally Posted by MrJack View Post
    Try watching some slow motion espresso shots on youtube (you can slow them down further with the video settings). Even for shots that look very even at normal speed, the espresso almost always appears at the outer edge of the basket first when you see it in slow motion.

    I have a few ideas as to why this happens in espresso pours (relating in part to basket shape and grinds distribution). It is consistent with studies of flow in other kinds of packed beds, which typically show higher velocity flow at the perimeter and mostly uniform velocity everywhere else (unlike laminar flow in a pipe, which is fastest in the centre).

    In my experience it is exacerbated in very tight pours - so I would expect grinding finer, over-dosing and very firm tamping would make this worse. Slower flow is the result of greater resistance (also caused by those three factors), hence the correlation between the two.

    The flow outside of the basket is dominated by the competing effects of gravity, viscosity and surface tension. If there is not sufficient (or any) flow through the centre of the puck (relative to at the perimeter), then the stream won't come together in the centre.


    Edit: Here is one I prepared earlier...
    Ah great post, and good to know, thanks MrJack!! Yeah must be more variables involved for sure... what are your thoughts on clumping, and whether that has any effect on density within the basket? You would think that any clumps would be 'tamped out' when tamping, but not too sure, seems like clumps are still high density/concentrated balls within the puck that may not get squashed or spread out during tamping... and I'm really thinking clumping affects how well you can effectively distribut too... (ie how the grinds move around/slot around each other when tapping the side of the basket for example...)

    And awesome vid! Watched that awhile ago, didn't realise it was yours! Really cool to see that the flow still starts around the edges.

    Quote Originally Posted by Yelta View Post
    Now for something completely different, still naked

    https://www.youtube.com/watch?v=OOgd9hitEAE
    Hahaha what the! Love it... Still on topic, still on topic

  49. #49
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    Behmor Brazen - $249 - Free Freight
    After much experimentation... and lowering the dose to get a normal 1:2 ratio shot, WDT just seems to dominate...

    Am just getting really great results using it.. It's not too much extra time taken, but I'd like to find a way to get the workflow faster if anyone who uses it has any suggestions.

    When I try to pull a double ristretto it doesn't seem to get want to come to a central pour (by double ristretto I'm talking a 1:1 ratio, ending it at about 35 seconds), but it just didn't seem to matter tastewise. Using WDT and the shot just looked fantastic, and tasted incredible.

    Changing back to a coarser grind and getting a 1:2 ratio it went central fairly early into the pour.

    Anyways, am loving the results of using WDT (after MANY years of me saying, "no no, I never want to go that far" haha).

    I'm also realising that distribution doesn't necessarily have to be set in stone, and needs to be flexible based on the coffee. The previous bean I used I didn't need to do WDT, but this bean which is a medium-dark roast it has been helping heaps.

    I reckon the skill of the barista is to note and adapt to these changes, and I think the intuitive and art aspect of coffee comes into it. For awhile I kept getting stuck in certain models or ways of believing I had to do things, but I'm thinking there is no 'one size fits all' distribution technique. It really really really depends on the bean and those particular conditions!

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