Results 1 to 9 of 9

Thread: Expobar Minore + K3T - underextraction issues

  1. #1
    Junior Member
    Join Date
    Apr 2010
    Posts
    6

    Expobar Minore + K3T - underextraction issues

    Gene Cafe Coffee Roaster $850 - Free Beans Free Freight
    Hello All,

    Long time reader, first time poster. In fact this site lead me to the very combo I have today, and picked them up from a sponsor :)

    I do apologise if this is the wrong forums.

    I have just upgraded to the above combo a week ago. I have run into a wall.

    I no matter what I do I am dragging out under-extracted shots. Running the Compak K3 Touch at its finest settings I am getting a 15ish second shot (well 2x30ml using double basket).

    I am tamping to 15kg (have the bathroom scales out, as I am trying to rule that out). dropping between 14-16g of freshly ground in the basket.

    The common understanding is to go finer to lengthen the shot time, but she doesnt go much finer :( If I tighten it more I get a slight sound out of the K3T which leads me to believe the burs a close to touching (and much further I cannot move it any further - when empty)

    A little lost to my problem at the moment and would welcome any suggestions or ideas to try :)

    Cheers
    Jason



  2. #2
    Mal Dimal's Avatar
    Join Date
    Oct 2004
    Location
    Warwick, QLD
    Posts
    17,115

    Re: Expobar Minore + K3T - underextraction issues

    Welcome Jason.... [smiley=thumbsup.gif]

    Sounds like you might be dosing a little light on mate. Try increasing the dose a little at a time until you reach a point where after locking in the Group Handle and removing it without pulling a shot, you notice it is just being disturbed by the Shower-Screen. When you reach this point, go back to the previous dose which should be close to ideal.

    Your finished product after grinding should feel similar to table salt when rubbed between the fingers and is a good starting point. I hope you are using high quality, freshly roasted beans there too Jason. Stale, old beans will certainly create similar difficulties to the ones you are describing. If you arent already, buy a pack or two of some of the great beans on offer from Andy at BeanBay, or one of our highly respected Site Sponsors listed over on the L/H side of the page....

    Anyway mate, see how you go and let us know the outcome. All the best :)

    Cheers,
    Mal.

  3. #3
    Senior Member
    Join Date
    Oct 2009
    Location
    Australia
    Posts
    675

    Re: Expobar Minore + K3T - underextraction issues

    Jason,

    If you bought it from a sponsor, give them a call. Dont be worried about asking for help. They might beable to offer a quick hands on training session to get you going.

    Does sound like dosing to me too, what does your puck look like after you remove the group handle?

  4. #4
    Member
    Join Date
    Mar 2010
    Posts
    33

    Re: Expobar Minore + K3T - underextraction issues

    Ive only had the machine Im using for a week ... and I had the same problem at first too.

    Kept going finer and finer and couldnt get it to ease up. Pushed the grinder to sub zero like you - and then it didnt work. Eased back from there of course.

    Cant say Im completely happy with where Im at now, but adjusting the dose/tamp has got things very close to where I want them to be. Making good, intense, consistent coffee now anyway. I was varying both the tamp and the grind each time but in the end, in general, I needed less coffee, but a slightly harder tamp ... if that makes sense.

    Fine line though.

    The main thing I needed though ... was confidence. Amazing the difference it makes. Havent pulled a "bad" shot in DAYS :)

  5. #5
    Senior Member
    Join Date
    Jul 2008
    Location
    Port Fairy
    Posts
    2,993

    Re: Expobar Minore + K3T - underextraction issues

    While you are figuring out dosage and getting consistancy up I have found a cheap 0-100g set of scales from evilbay a great help. If you are playing heavily with grind size simply looking at whats in the basket is not a good guide of quantity due to the increased settling as you go finer.

    Eliminate one variable then change just one other and try is the easy way to go *:)

  6. #6
    Junior Member
    Join Date
    Apr 2010
    Posts
    6

    Re: Expobar Minore + K3T - underextraction issues

    Thanks for all the replies guys. Very very helpful.

    The puck, well looks fine. But then again I am not too sure what I am looking for. Comes out in 1 piece. Looks fairly consistant. But again, i havent much to compare it too.

    Thanks coffeeshot - good to hear I am not alone there :)

    I went an got a few hundred grams of coffee beans freshly roasted ground tonight, dosed it up. 14g and 15sec shot. I then followed advice by mal(about 17.5g - I got a digital scale but only 1g resolution.) *Single 15g tamp, and got my best shot yet.

    ~25sec about 30ml. Looks like it might be a grind and dose issue (though I am sure I had gone as high as 18g).

    So I will experiment with the pre ground stuff a little more. Then try to configure my grinder to produce a roughly similar grind as the "shop" as a bench mark.

    I was pretty excited to pull such a nice shot (well for me:)). So I had the espresso shot, and then made a cappa with the other :) no sleep for me tonight!

    Thank very much all, very much appreciated all the quality feed back. Ill make sure I update this once I sort things out, in case another guy is in the same boat later on down the track.

    Cheers
    Jason

  7. #7
    Junior Member
    Join Date
    Apr 2010
    Posts
    6

    Re: Expobar Minore + K3T - underextraction issues

    I also picked up some of those cheapo scales. Mine are only 1g increments. These (0.01) will do much better, thanks for the tip.

    -J

  8. #8
    Mal Dimal's Avatar
    Join Date
    Oct 2004
    Location
    Warwick, QLD
    Posts
    17,115

    Re: Expobar Minore + K3T - underextraction issues

    Thats good news Jason.... [smiley=thumbsup.gif]

    When its all said and done, I think it just comes down to being as consistent as you can be with each facet of the technique and only making small singular changes as you try to dial the machine into the beans you have. Much better to creep up on a God Shot than to attack flat out and miss it altogether.... ::)

    Anyway mate, youre getting there and thats great.... 8-)

    Mal.

  9. #9
    Senior Member
    Join Date
    May 2008
    Posts
    437

    Re: Expobar Minore + K3T - underextraction issues

    Couple of suggestions as you move through this phase. (Yes its a phase, it will end as your technique develops each day.)

    When your grinder dumps into your portafilter, make sure you move it around while grinding to arrange as even a dump load as possible across the basket before you level off or change the grammage. Compression in one spot and weaknesses elsewhere can cause channelling (bitter overtones).

    While youre experimenting with a new grinder, dont be afraid to updose as high as you can go before your shower screen touches it when the PF is inserted. At least youll have a better chance of a nice shot while youre fine tuning your grind. Playing with perfect 14g shots while trying to get a 30sec pour this early in your journey with (very nice) new equipment is cutting it fine. It takes experience and consistency in technique, and likely to be more miss than hit this early.

    Figure out what that updosed grammage is, use it as your new standard measure, then make your next priority to check your time to blonding and refine your grind around that. Itll be your ball park, and youll be getting drinkable coffee at the same time if you stop your shots just short of blonding.

    From there, your taste buds do the testing and gauging, and you can decide on whether to play around with just shot volume (try a ristretto), or grammage/flavour/shot volume, or to play around with grind size/flavour/shot volume, and eventually to play around with every variable.

    Bear in mind always its whats in the cup that counts. My champion trainers drummed it into me, and its totally true. It means every variable is a variable, and the guidelines are just that.

    You will develop preferences. Mine is for updosed ristretto shots (short volume measured shots) for many roasts I do, and I use these as a base for milk drinks. I love the sweetness and intensity. Every so often I come across a new single origin Ive roasted or a different roast depth that I like better as a full espresso shot. Its all preference. And its your tastebuds that are your best guide.

    Oh yes, and as for the puck... youll find with ristretto shots, or shots that havent yet been fully extracted that a little puddle of wetness will remain on top of the puck. If the puck has any tiny holes in it (channelling), you need to look at distribution and perhaps tamping. If you can press your finger into the puck just after the shot and it compresses just into the top mm or so before it becomes dense youre at about the ball park for a full extraction. Too dry/too hard = over extracted.

    Have fun. It is a great journey. :)

    EDIT: last suggestion for the evening; if you can afford it or know someone with one, a bottomless/naked portafilter is a very nice to have item. It narrows down your technique problems very quickly!



Similar Threads

  1. Expobar Minore IV pump issues
    By FineGrind in forum Brewing Equipment - Pointy End ($1500-$3000)
    Replies: 3
    Last Post: 16th February 2013, 10:25 PM
  2. Expobar Ruggero Issues
    By whitie8000@hotmail in forum Brewing Equipment - Extreme Machines ($3000+)
    Replies: 7
    Last Post: 14th June 2012, 06:46 AM

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •