So I started out, pretty much, always using a puck disk. Not for any magical properties, but just to reduce the mess, and a 3rd-party basket because.. well, internets. And it worked. I always had really ‘perfect’ looking, dry pucks. Awesome. Unfortunately, the same has not yet been said about my coffee. Anyway, jump forward and I’m trying to dial in an ‘easy’ blend - the Fudge from Rave - and it’s still coming out too sour, despite trying various tests around a basic 1:2 in 25-35. So I decide to go back to ‘stock’ everything . I use same 17g in the ECM 21g basket that came with the bottomless portafilter, the same grind and no disk. Whilst the shot is by no means perfect, it’s ‘balanced’. Yes, there’s still more acidity than I’d like, and the bitterness is starting to appear, but the two sort of make it much ‘smoother’ than I’ve ever managed before. Of course, the puck is a sloppy mess (likely somewhat due to 17g in a 21g), but this is huge from a results perspective. So the next day, I try adding the disk back in - no other changes. It runs the same dose in 9 seconds less, and the balance has completely gone. Okay, so I grind one-notch finer on my C40-red, and it slows down to a more reasonable 27s, but still so much more acidity and not a hint of balance. I go back to stock again, just to verify my previous result, and sure enough it’s still reproducible. Now this is just adding back the disk (A shades of coffee 1.7mm - the 0.2mm made no difference) and when using the pullman basket (17-19) as well as the disk, the time was around the same as stock (but so much more sour). For now, I’m going to stay at stock and just dose up 1g, to see if I can improve the wet puck - although at the same time I’d like to lower the strength, so I guess I’ll need to grind coarser a notch or two as well, to still get a similar yield/time and keep everything else in the same ballpark. I’m sure most people will say “well, DUH !” but nobody ever seemed to stress that puck disks and/or ‘better’ baskets would make such a huge difference to the variables. Perhaps they mentioned in passing, but generally it seems to be that they’re suggested to be helpful in making things better (and they likely do in some ways) but not enough warning comes with them. Maybe I’m still screwing other things up as well 🤷🏻♂️ I’m working through, changing one thing at a time and constantly gaining experience, but it’s clear there’s so much more to go. At least I’m not having any (obvious) channelling issues to add to my woes.

How do you clean yourpuck disk and how often?

dutchy101 it’s thoroughly rinsed after every shot, and puly caff weekly rinse. The same for all of my tools.

Think that rules out the clenliness of the disk itself. When I bought my Minima, just over a year ago, I found the pucks to be soggy and bought a mesh disk to help with this. At the same time I bought an IMS basket and VST basket. I suck with the VST as it was designed for an 18g dose (my preferred dose) whereas the IMS was 18-22g. I found out that dialing in between the 2 baskets was a nightmare - I also had a puck screen to find my feet with. I decided I needed to stuck with the VST and have done since. My screen was a mesh one, which I’ve recently changed for a Shades Of Coffee screen. This also took a bit of getting used to. I also decided to realign the burrs on my grinder and do some shimming around the same time. (I know haha). From my experience, changing too many parameters at the sane time is not the best idea.

Puck disks and Baskets and all that jazz

mobius

dutchy101 What differences did you find between the ‘mesh’ screen and the Shades of coffee, assuming they’re both a similar 1.7mm ?

The 0.2mm ‘screen’ did nothing to affect the shot for me, but equally didn’t seem to stop the messy puck either. I’ll try it again, once I’ve increased the dose and seen that result.

Definitely sticking (and learning) stock equipment first, seems to be the easiest way to learn from common guidelines, but I’m also noticing that despite the ‘common ground’ there are so many outliers as well, so short of having a trained barista use your gear and dial-in a ‘perfect’ shot, there’s nothing really to do but keep trying out different options - as you say, changing one thing at a time - and seeing where that ends up.

A lot of coffee - especially when only able to try a few each day - and time, but hopefully it will work out in the end.

Cuprajake

The disc speed up the shot, so you can grind finer, but then you may be over extracting

Fwiw I have a disc sat in a drawer lol

Just have to clean those sloppy pick or leave them in the machine for a tad longer

Msmk0

I use an original Bplus disc for my double and triple IMS baskets (55mm) , but is to big for my Dalla Corte single basket (54.8mm).

Single IMS and the single one that came with the ACS EVO are smaller and my Bravo tamper (54′7mm) does not fit there.

I use the single for my wife lattes, as I prefer double espressos.

I noticed notable (ha!) differences using the Bplus puck next with the IMS shower on water distribution, no obviuos channelling and more rounded balanced results.

So I bought a cheap AliExpress puck disk of 53.5mm (there are no bigger).

First one was 1.7mm 150microns. Results were catastrophic… flow was absolutely clogged as I grinded really fine, but grinding coarser didn’t help.

Then I bought 1mm 150microns. Much better, but far from the Bplus one. I keep using it beacuse it makes the puck more solid and the whole experience is cleaner.

Although, the AliExpress puck gets stuck to the coffee and it get far dirtier than the Bplus one.

Bplus is noticiably heavier, material seems different and rhe mesh is much more dense, but at the same time water flows better. And yes, way more expensive, but the daily experience is also way better.

Rob1

mobius a basic 1:2 in 25-35.

Ok, nothing about this is guaranteed to give good results. Low ratios are hard to extract properly, you also say you want to decrease the strength….pull the shot to a longer ratio, decrease strength, and increase extraction yield. You may be under extracting and the bitterness you mention creeping in is almost certainly not over extraction.

mobius

Rob1 I realise that nothing is guaranteed. All I’m trying to understand is a basic ‘starting point’ and the various disks/baskets seem to change that baseline, so I need a lot more experimentation to understand ‘how’. It just surprising that it’s not mentioned much - perhaps because most people using them are far more experienced and just expect a more difficult/lengthy dial-in on new equipment ?

I certainly wouldn’t call 1:2 a low ratio though. It’s the default espresso - the normale ?

I do agree that the bitterness may not be over-extraction - it’s not harsh, just the noticeable ‘dry’ mouthfeel - but is most probably a lack of the acidity being balanced. I’m definitely under-extracting, noticeable by how sharp the acidity is on a bean that really shouldn’t be. I’m just trying to work out (and will continue to) how these other variables also affect things.

Rob1

mobius I certainly wouldn’t call 1:2 a low ratio though. It’s the default espresso - the normale ?

The 1:2 is a relatively recent development and part of the trend towards more concentrated shots. Fairly certain it was popularised in WBC competitions by baristas using EK43s. The normale is about 7g to about 25ml…that’s not a 1:2 ratio at all, it’s closer to a 1:3.

The discs take up headspace and larger baskets have more holes…how all this influences extraction is probably theoretical. If the screen causes the puck to wet slowly the shot will run faster, if not it’ll be slower. Flow rates influence extraction.

LMSC

IMO, you may want to focus on getting a cup you like than a beautiful looking spent puck. The latter is irrelevant. You said the shot without the puck screen is better.

If I were you, I will keep the puck screen aside. I am not a fan of puck screen, although people love it. It can push the extraction to extreme. It’s a big faff and a mess to clean the puck screen. It is easier to clean the shower screen, which has never been messy for me at least. It only requires a simple wipe. I don’t even drop the shower screen every week, let alone every day. But, I don’t dose more than 17g on my IMS 18g basket.

A soggy pick may mean, for example, the grind size is on the finer side and the water is struggling to go through for some reasons.

As Jake said, leave the PF a little longer before removing it from the group. Rather than grinding coarser, tamp loosely because coarser grinding is likely to result in faster flow during the second half of the shot.

What are the tasting notes mentioned on the bag? Perhaps, the bitterness is a part of the notes (chocolate, cocoa, even toffee, molasses,…)!

mobius

LMSC Thanks - I am focusing on the the taste of the cup, first and foremost. This discussion is more of my ‘side ranting’ and experimenting alongside that - understanding how everything comes together (or doesn’t).

I actually have a cup I like now - I dosed up (stock basket, no puck disk) to 18g this morning, and it brought together the balance nicely. I will now play with the yield and just run it a bit shorter/longer either side to see what difference that makes. I’m still perfecting getting to within a gram of my expected yield as well, as it’s clear that just a few grams can make a fair difference in the cup.

The PF is in the group until I’m ready to distribute/tamp. I’m actually fairly happy with my ‘stock’ setup on this bean now, but just know I can ‘make it better’.

Tasting notes are… Fudge. That’s it. As it is, the acidity/bitterness are balanced where I am - when I ‘nail’ it - to be sweet (or my interpretation of that) and it’s an enjoyable cup. I am just refining that sweet spot and trying to improve my overall technique to hit it more repeatedly (within reason). My wife (who is most certainly not an espresso, or coffee, drinker, has noted on a couple of occasions that she thinks it’s balanced and has a hint of fudge aftertaste, so that’s close enough).

The next steps will be with a new bean, and a bigger bag, to give me more experimentation time once I’ve dialled it in. This will be the bean I tried in the roastery, so I also have a baseline expectation of the outcome.

The journey is great, but as a Software Engineer (where everything is reproducible/idempotent), the variance can often throw me. This is part of the aspect I’m ‘enjoying’ - the analogue nature of it.

steve_07

I thought a puck screen was just for better water distribution and keeping the shower screen clean. From tests people have done extraction difference has been negligible/scatter at best. A paper filter on the bottom of the basket seems to increase extraction though.

mobius

steve_07 I’m only using it for the distribution and cleanliness. I don’t really care about extraction changes - which is also why I was surprised at the flow changes.

Platypus

steve_07 Me too

mobius

Rob1 Really interesting ! I appreciate the insight, thanks.

Also interesting that a slow puck-wet causes a faster shot. Do you mean the flow rate will be faster, or just that the shot will extract faster, such that it needs to be stopped earlier (and thus a ‘faster run’) ?

Rob1

mobius Flow rate will be faster and extraction will increase but that doesn’t necessarily mean it needs to be stopped earlier, it quite often doesn’t but you may find dark roasts come out too roasty.