Announcement

Collapse
No announcement yet.

EM6910 - impossible to pull a single or double with the same extraction time.

Collapse
X
 
  • Filter
  • Time
  • Show
Clear All
new posts

  • EM6910 - impossible to pull a single or double with the same extraction time.

    Hi guys!

    So, my learning curve is fast... I must say, a EM6910 with a BCG800 grinder is a very good combination. If you add an espro tamper, even better

    Now I get consistent double shots with 20 grams (60 ml) @ 25~30 secs in the original EM6910 basket, but I realised that when I pull a single (with 14 grams), there is no way I get the shot in 25~30 secs. I started to wonder why...

    So, I started digging out on the relationship between a single and a double basket... From what I read (and please correct me if wrong) single and double baskets are designed to make the shot take the same amount of time while having different throughputs (i.e. 30 or 60 ml). Why? The single basket is designed to restrict water flow and also contains less coffee (7 grams), while in the double, more water is allowed to flow but more coffee is packed (14 grams), which should make almost the same resistance as the single basket (lets call if physics).

    Having this in mind, I realised that I was dosing 14 grams in my single and 20 grams in my doubles (maximum I could fit in the double basket)... Why these dosage? Because its the dosing level I found that would provide me with a good shot and a lovely puck. Applying the same consistent grinding and tamping, with this dosage level there was no way I could get the same brewing time on a single or double. Reason is simple, I am missing 8 grams in the my double basket (i!

    After applying this reasoning, I decided to do some experiments on lowering the dosage on the single basket by always adjusting the grind to get 30 ml in 25-30 secs. The idea was to reduce it to 10 grams and then test the timing on the double. Results:

    - 10 grams: After adjusting the grinder, the end result was the puck stuck to the shower screen (horrible)
    - 12 grams: A horrible muddy puck.
    - 14 grams: good puck and extraction.

    Conclusion: at least with the default EM6910 baskets, its merely impossible to get a single and double extraction with the same timing and grinding setting. EM6910 likes high dosage and the only workaround is to grind finer on the single basket.

    Any comments are always welcome... just wanted to share my thinking.

    Cheers guys!

  • #2
    Your conclusion can be extended to pretty much all baskets and machines in my experience. Once you have your grinder dialled in for your double, leave it there. Throw that evil single out!

    BTW I agreee that 19-20g of coffee in the EM6910 baskets makes a great cup. I still use those baskets in my Rocket PP with slightly less coffee as they are much beter made than most (and my tamper is sized to them)

    Happy brewing, JB

    Comment


    • #3
      Originally posted by cherni78 View Post
      Conclusion: at least with the default EM6910 baskets, its merely impossible to get a single and double extraction with the same timing and grinding setting. EM6910 likes high dosage and the only workaround is to grind finer on the single basket.
      You can get the same extraction times but I find that I have to grind coarser for the single (only 2 or 3 clicks), not finer.

      The baskets do like to be updosed as compared to the standard 7g and 14g respectively, I think they were designed that way.

      Comment


      • #4
        Originally posted by shawty View Post
        You can get the same extraction times but I find that I have to grind coarser for the single (only 2 or 3 clicks), not finer.

        The baskets do like to be updosed as compared to the standard 7g and 14g respectively, I think they were designed that way.
        +1

        I normally use the single basket and have to grind slightly finer for the double.

        Comment


        • #5
          rather than mess around, the single baskets stay in the cupboard. the only time i've ever used one is to check the 'sweet spot' and i even disregard that now as well.

          if you want a single, just let one spout go to waste, or have a double shot. much easier than constantly changing grinds etc.

          Comment


          • #6
            Hi Guys,

            Thanks for the feedback. I must agree, that 20g does a wonderful shot in the EM6910... my issue comes with my wife, she doesn't like strong coffee, so for her is a single shot. That is when I started wondering what was the difference between 14g in a single and 20g in a double... Technically, 14g is a double

            Well, I will waste one spout (although it hurts)...

            Still, I think we should be given the choice to use single baskets with the proper dosage... I might try and get one that allows less dosage and see the results (experimenting).

            One question though... we are all updosing and we love it... I wonder what the "real" espresso tastes like if you stick to the 7/14g rules. Just wondering!

            Cheers!

            Comment


            • #7
              Originally posted by cherni78 View Post
              Hi Guys,

              Well, I will waste one spout (although it hurts)...
              Why waste it?
              Put it in the fridge and use it to make an iced coffee or a frappe.

              Comment


              • #8
                Originally posted by cherni78 View Post
                Hi Guys,
                One question though... we are all updosing and we love it... I wonder what the "real" espresso tastes like if you stick to the 7/14g rules. Just wondering!
                Cheers!
                Very weak

                Seriously.. I reckon I'd have to cut the pour at about 10-15ml and end up with a sloppy puck as well!!

                Comment


                • #9
                  Originally posted by shawty View Post
                  Very weak

                  Seriously.. I reckon I'd have to cut the pour at about 10-15ml and end up with a sloppy puck as well!!

                  jajaja, well, I just bought a couple of new baskets from one of the sponsors of this forum

                  Lets see how it goes!

                  Comment


                  • #10
                    Originally posted by cherni78 View Post
                    Hi Guys,
                    my issue comes with my wife, she doesn't like strong coffee, so for her is a single shot.

                    Well, I will waste one spout (although it hurts)...
                    Do you not have the other shot at the same time?
                    or if i'm making an odd amount i just stick my nice espresso cup underneath and pour the odd (double) shot first and drink the shortie while i'm making the rest.

                    I only use 180-200ml cups (or even 90mm for some occasions) that don't require a double in each.

                    Comment


                    • #11
                      Originally posted by Robbks View Post
                      Do you not have the other shot at the same time?
                      or if i'm making an odd amount i just stick my nice espresso cup underneath and pour the odd (double) shot first and drink the shortie while i'm making the rest.

                      I only use 180-200ml cups (or even 90mm for some occasions) that don't require a double in each.
                      Well, I do use doubles... I like a "double cortado"... double shot in a 90 ml glass and top up with hot milk (not very foamy).

                      Comment


                      • #12
                        Hi Cherni78,

                        You definitely have the makings of a coffeesnob
                        From my experience the 6910 single and double baskets are not designed well as a pair. This is because you need to change your grind setting to swap between the two.
                        I was still able to get great shots from the single, but the practicality of changing grind settings all the time resulted in me rarely using the single. A shame.
                        On my current machine (Musica) the stock single and double baskets are matched well so I don't need to adjust the grind. And I swap between the two all the time, I'm not a fan of wasting 1/2 a double shot.

                        Some more advice on the 6910, find the right dose level and stick to it. Measuring the grams will definitely give you more consistency, but I guarantee you will grow out of it

                        Enjoy

                        Comment


                        • #13
                          The single and double baskets do work well as a pair - remember that the single isn't half the double! If you're using the single all the time then by all means adjust dose and grind for the single. But you couldn't then use the double basket with the same grind. But if you use both baskets then it's the dose that changes to use the single, not the grind. The initial dose stage should be the same as the double if you dose by eye (overfill, tap to settle, level & tamp), here's a good starting point:

                          • Overfill the single basket
                          • Tap twice to settle
                          • Level the grounds using the doser lid (or a saucer) - this results in a pronounced concave bed in the single basket
                          • Tamp lightly - just rest the tamper on the grounds and press with fingertips.
                          • Lock & load, pull the shot - you'll find the flow rate is pretty well right, just stop the shot based on colour but it'll be somewhere ~25ml. But if it were too fast, use a larger saucer to level or vice versa...


                          This isn't unique to the EM6910 btw, it's valid for most single / double basket pairs (though if you're into super dooper special after market jobs, all bets are off!).

                          Comment


                          • #14
                            Originally posted by cherni78 View Post
                            Well, I do use doubles... I like a "double cortado"... double shot in a 90 ml glass and top up with hot milk (not very foamy).
                            roger-that...
                            my wife and I usually drink a single cortado, my glasses are only around 75ml.

                            Originally posted by WiredArabica View Post
                            The single and double baskets do work well as a pair - remember that the single isn't half the double! If you're using the single all the time then by all means adjust dose and grind for the single. But you couldn't then use the double basket with the same grind. But if you use both baskets then it's the dose that changes to use the single, not the grind. The initial dose stage should be the same as the double if you dose by eye (overfill, tap to settle, level & tamp), here's a good starting point:

                            • Overfill the single basket
                            • Tap twice to settle
                            • Level the grounds using the doser lid (or a saucer) - this results in a pronounced concave bed in the single basket
                            • Tamp lightly - just rest the tamper on the grounds and press with fingertips.
                            • Lock & load, pull the shot - you'll find the flow rate is pretty well right, just stop the shot based on colour but it'll be somewhere ~25ml. But if it were too fast, use a larger saucer to level or vice versa...


                            This isn't unique to the EM6910 btw, it's valid for most single / double basket pairs (though if you're into super dooper special after market jobs, all bets are off!).
                            ^^ that was the procedure i worked out for using the singles in my 6910,
                            but now i just drink the extra shot while i'm making others...

                            Comment


                            • #15
                              Originally posted by WiredArabica View Post
                              But if you use both baskets then it's the dose that changes to use the single, not the grind.
                              All I remember with the 6910 was:
                              If you maintain the same dose level (with respect to shower screen) for both single and double baskets, then you'd need a significantly different grind to get the same extraction times. Of course adjusting the dose level will compensate for this but my experience with the 6910 says that its wasn't very effective. This is probably because the difference in dose level required is so much that you have to go too far away from the 'optimal' dose level of the machine, which wasn't worth it.

                              Comment

                              Working...
                              X