MWJB it seems like my dial in journey is much longer than others :( I tried 3 shots today:

4/ G1.8.0/ brew time: 15s @15lbs/ 1:2.2 <2.5/10> Significant channelling, watery shot

5/ G1.8.3/ brew time: 8s @20lbs/ 1:2.1 <3.0/10> Channelling and watery

(I also tried a backward shot by going finner than the last shot yesterday)

6/ G1.7.0/ brew time: 17s @28lbs/ too coarse/ 1:2.1 <4.0/10> Some channeling

I can’t get any implication from the shots on which direction I wanna go for the next shots. Should I continue going coarser or finer? The only reason I can think about the confusing result is puck prep. But I think I am reasonably careful on puck prep what I did was WDF the ground in robot basket, from bottom to mid, to top grind try to stir a bit more to redistribute even the ground and avoid void in middle I then use the tamper to tamper the coffee by fingers I lower my body at the same level as the top of the basket so I can make adjustment during tamper if the handle of the tamper is not at 90 degree to the opening of the basket I didn’t use lots of force but only a firm downward pressure to tamper.

Again, appreciate any feedback or advice you may have thanks

      Knluk I’m at a loss as to why yesterday’s shot at 1.7.2 was 5.5 & the best you had up to that point, but now 1.7.0 is too coarse & 4.0 ?

      Don’t fret over perceived channelling.

      Make some more at 1.7.2 see how they average.

      I don’t WDT.

          Knluk

          MWJB asked you to repeat the best shot you got so far!

          When you get a noticeably improved shot, make few at those parameters to make sure things are consistent, before making more changes

          Your best shot so far is

          Knluk I was finally able to pull a shot with 7/10 score with 1:2, 15g in and 30g out with 1.7.0 grind size.

          Have you repeated this to ensure consistently, which will give you confidence in your coffee making, the lever and amongst other things? It is always a good practice to stick to one beans for a period of time until you have gained enough experience and gain confidence.

          We can understand you want to try other bags. It is fine if that’s you want to do. It is up to you! But, it gets harder as you swap the beans. As such the manual lever is hard to get used to and develop proficiency. You have worked very hard to some gain confidence. The result was the 7/10 shot. Please stick to that as advised by him.

          Most of us always use the previous best parameters (temp, grind settings, ratio, …) as the default starting point when we dial in a different bag! It is likely to require only a few adjustments. :-)

                MWJB I have the same feeling. Made me feel directionless. Make I should try something totally different on what I am trying …

                  MWJB could you share your best practise for puck prep? I made little improvement from time to time. Almost eliminated all channelling previously. But now appears in many of the shots.

                  • MWJB replied to this.

                      LMSC I switched to new beans most because the last bag (no roast date) was bought as emergency while I am resting my new beans.

                      I repeated the best shot on the Blackcat Brazil but very bad outcome. I will stick with this bean until it is used up. And then will move to the Chocolate Blend (I have 500g of that) so I will have more beans to dial in. I think I need much longer time than average people to learn the dial in. I talked to people in the Robot group, vast majority of them got very good shot in the first shot after purchasing the Robot 🙀 and they sound relatively careless on puck prep/ temp, etc. so I keep on thinking what I did wrong fundamentally but really not clue.

                      With lots of failure feeling today, I went to just another local cafe. They’ve got La Marzocco machine and VA grinder. I had a double espresso, which was fruity and nice sourness. I presume they are not a particular specialty cafe as half of the shop sells nuts, organic dried fruit, …. But the nice coffee shows me how much improvement I can achieve if I keep trying. (Btw, will ask them the beans they used once I finish the Brazil, CB , and Dock Blend).

                      thanks guys! Really appreciate the advice and discussion. I think I should just clear up some mind flog and find a new starting point to dial in the Brazil before it is used up.

                        Knluk Firstly I don’t worry about what people call “channeling” if the shots taste good, I use a PF with spouts, or a bigger cup to catch the spritzes.

                        I grind to the cup/catch cup of the grinder, shake the grinds then dump them into the PF basket via funnel, tap straight down a couple of times, then 2 or 3 sideways taps (heel of hand on side of PF) to level the bed, tamp once straight down, straight up & out, brew.

                        How would you score the shot from the LM at the nut shop?

                            MWJB that sounds like a great suggestion to experience. The robot comes with a sing spout PF. Will use it and see how it goes by not seeing.

                            I will also try your puck prep approach. Sounds very simple but less is more I guess. I also tapped the sides of the PF (which is also the basket for Robot). But eg when I tap the right ride, I will see there is a small gap between the puck and the right side of the PF. I then tap the other side and ended up tapping 7-8 times. I didn’t actually count but I tap 360 degree until I see no gap and the puck is level.

                            After tapping the sides a couple of times, do you normally get a level surface? Or i shouldn’t aim for a very level surface as it will be taken care of by tampering?

                            also, will you try to break the clumps if you see it?

                            I will try new puck prep tomorrow and start everything from the last best shot I have at grind setting 1.7.0.

                            The cafe one I tried today was a 8.5/10. I be a happy man if I can continue pull that kind of short with one type of bean.

                                Knluk Clumps should be broken up when you shake the grinds in the grinder cup.

                                Try and get the grounds into the basket without big voids at the sides, after a couple of sideways taps, yes the puck is level enough to tamp.

                                  Knluk I may be completely wrong, and I’m no great expert, but I’m thinking you may be overprepping… the more you “mix” with WDT and tapping, the more you will get fine particles moving to the bottom of the puck and a (not) nice sorting of progressively coarser particle as you get to the top. The sorting takes surprisingly little time/effort to happen, but it’s not a good thing.

                                      CoyoteOldMan have fun in France!

                                      This sounds probably the cause. I recently home made a WDT tool with wine cork and sewing needles. I stir in small circular motions from bottom (really touching and scratching the bottom of the PF) to top because I learnt the importance of even distribution.

                                      Re the clumps, I kept thinking why I had quite a bit of clumps maybe because I tap the sides of the grinder and also tap the bottoms and the bottom corners of the collecting cup attaching to the grinder to the table pretty strongly to try to get the last big out from the burrs. Because I saw some particles between the burrs. I did it for 15-20 times depending on mood. I developed this habit gradually and maybe this slowly impact my puck condition.

                                        Knluk I would stick with the bottomless basket as the spouted PF will reduce the temperature of your shots unless you preheat it. You can also get a better idea of what’s happening with a bottomless, especially with preinfusion (as the basket slowly starts dripping), even though you shouldn’t let some channeling make you think that the grind is incorrect!

                                        I also think your shots seem messier because it’s a lighter roasted coffee and so is harder to extract as easily. With a very dark roast this may look nicer to the eye and extract easier because its more soluble, but a lighter coffee can cause more issues to fully extract. I don’t think your preparation will necessarily be getting worse. It takes time and patience so just try to stay consistent with everything you do and change one setting (grind) for the time being.

                                        With the shot you grinded finest but there were channels, did you taste bitterness like with the last coffee beans?

                                            FadedFrontiers thanks. Good point on the temp.

                                            Yes. It is mainly the striking bitterness we cannot get rid of. And yes- from the colour, it is a pretty lighter roast compared to the oily bean I had before

                                            I think one of the tricky part confused me before was the relationship between grind size/ pressure/ time. Eg when I could get close to acceptable pressure (day 5-6 bar) and time (eg 30s), but the taste is bitter, should I use to coarser grind. But when i continued to move to the grinder size, either or both of the pressure and time will change to a funny level. But I got it now that I should ignore the pressure and time first. Still not sure what will happen next but the beautify of this forum is I can restart and report back the progress step by step for advice. I will restart from 1.7.0 grind today.

                                              Continue working on the Brazil beans today. I kind of doing some unlearn and relearn here and try to do simpler puck prep for better extraction. However, I still find quite significant clumps most of the time even after tapping the grind collector lightly and tapping the sides of the PF 3-4 times. And up and down tapping the bottom of the bottom of the PF to the table mat. So I lightly use WDT to break down the whole surface section to get rid of the clumps.

                                              I tried to give it a bit more patience this time and changed grind size really marginally. So not much more observable indication can be drawn. But at least I improved my reporting skills :)))

                                              (Texture: 10 is thickness, 5 is medium, and I prefer 6-7)

                                              During the pull, I did not pay any attention on channelling , brew time and pressure. But I watched the filter bottom video afterwards and report anyway (10/10 means channeling free)

                                              Any comments will be highly appreciated

                                              • MWJB replied to this.

                                                Knluk How do you propose to influence the “thickness”? This would normally be achieved by grinding finer (which increases bitterness) and/or pulling shorter. (It’s not something I would personally aim for as short, thick shots can get in the way of the flavour, but everyone has different preferences).

                                                The shot that channelled more tasted better (or at least no worse), so ignore what you think is channeling (it probably isn’t).

                                                Isn’t your pressure in pounds, not bar?

                                                    MWJB Thanks! Make a lot of sense regarding thickness.

                                                    I re-examine the video of the last shot today. I think the flow is not as full compared to the dark roast. And weaker in some of the hole but you are right that there is no channeling. Not sure how I made that remark :) . I probably just prefer the beauty of the full of crema flow. But that’s not as key as the taste.

                                                    Yes. Should be in pound. But I just take it by feel. Don’t want to overcomplicate it as advised by you before.

                                                    Does it make sense to go coarse? Appreciate that.

                                                    • LMSC replied to this.

                                                        Knluk It’s a good shot, although the beading starts on the top and left to right on the video. This suggests a potential weaker spot on the top and left as per the video. But, I will be happy with that and won’t worry about your WDT. This just leaves one doubt if you are actually confusing the natural bitterness in the espresso with medicinal bitterness. Is it medicine or a paracetamol bitter?

                                                            LMSC cool. That means I just not familiar with the relatively light roast beading only.

                                                            Hm… honestly I am not good at describing taste. But I think it lean more toward to the medicine like bitterness and the after taste bitterness leaves there long. Compared to the expresso I had in cafe (where I prefer slightly more bitterness than sourness), it is different but not hugely different by nature. But the bitterness in my shot Is definitively striking and not pleasant. Sorry I cannot describe it better. But I appreciate your help.

                                                            If my beading is okay, I will then move to coarser to try until the shot got problem such as very watery and extremely short brew time. And at that time if I still have this Brazil beans left, I will go another direction to try something coarser than the start point, ie 1.7.0. Make sense?

                                                                Knluk I would try pulling this grind setting again but with less preinfusion time, see how that tastes. If it’s still bitter try lowering temp by a degree or two (temp may also be worth adding to your chart too to keep track of).

                                                                I also recommend you up the dose from 15g to 16 or 17g of coffee. The Robot is capable of doing doses as small as 12-14g but I’ve always found those harder to get the most out of. It’s far more forgiving with larger doses which I imagine is down to the depth of the basket.

                                                                    FadedFrontiers sure thing. Do as instructed :)

                                                                    1. The first shot was similar to yesterday’s. Temp was reduced from 95c to 93c and increase dosage from 15g to 16g. Also, preinfusion was shortened to 5s.
                                                                    2. The second shot - I further increase dosage to 18g. This showed observable improvement. Still bitter but less striking and less long lasting. But LMSC i paid attention to it. Yes- I am pretty sure that it is me medicine like bitterness. But this shot is marginally drinkable. I don’t enjoy it much. But I will drink it when I crave for coffee. Also, notice some floral smell and after taste. But lack of sweetness.
                                                                    3. Third shot - I kept everything the same but with some confidence built up(?) I decided to coarse up the grinder by one click and pretty confident that it will show slightly improvement. But it returned to the level of yesterdays. Pretty frustrating for this :( Below is the video of the last shot.

                                                                    With my fast speed wasting bean (but I appreciate all the learning), I will use up my Brazil bean in a day or two. Plan to stick to the best shot today and try to pull a shorter shot. My thinking is to get rid of the last part of the shot which is bitter. Does it make sense to all fellow members here?