Announcement

Collapse
No announcement yet.

Greg Pullman's portafilter pressure gauge on the road

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

  • matth3wh
    replied
    Righto, I've paid up... add me to the queue. I've sent a message to Janus.

    Matt

    Leave a comment:


  • matth3wh
    replied
    Thinking about joining the queue. I know MB21 was also considering it.

    Leave a comment:


  • Janus
    replied
    Greg Pullman's portafilter pressure gauge on the road

    Whoops figured it out.
    Last edited by Janus; 5 September 2017, 11:38 PM.

    Leave a comment:


  • gregpullman
    replied
    Thanks Janus... if anyone else wants to use the gauge please check the instructions at the start of the thread. Janus should have it around the end of this week so I'd imagine it'll be available mid-September-ish.

    Greg

    Leave a comment:


  • Janus
    replied
    Paid up, please add me to the queue.

    Leave a comment:


  • gregpullman
    replied
    Hi @Janus,

    Yep as long as someone needs it it's still available. Just follow the instructions in the first post and I'll send it out to you.

    Cheers,
    Greg

    Leave a comment:


  • Janus
    replied
    Is this still doing the rounds?

    Leave a comment:


  • JojoS
    replied
    I remember the advice given to me by the guy I bought my naked portafilter for my Gaggia Classic from. "If you do not like how the shot you pulled turns out, just do it again. Don't change the dose or the grind setting. There is a high chance it is just your fault." Best advice I got when I was a newbie to the world of home made espresso.

    Leave a comment:


  • Dimal
    replied
    Yep, it sure does...

    And with machines that lack an OPV or a Spring Lever machine, etc it's even more important...

    Mal.

    Leave a comment:


  • JojoS
    replied
    Does that mean that everything revolves around how well the coffee puck in the filter basket is prepared that will determine the actual brew pressure and flow rate?

    Leave a comment:


  • MrJack
    replied
    Yep.

    All I'm saying is that it won't maintain 9 barg at all flowrates - so there isn't really _an_ ideal brew pressure.

    Leave a comment:


  • Dimal
    replied
    but you are effectively calibrating the OPV/pump gauge for a single flowrate.
    But, isn't that the intention?
    Identify a median flowrate and then adjust the OPV/Pump Bypass Valve to achieve this at the Group?

    Mal.

    Leave a comment:


  • MrJack
    replied
    Originally posted by symphonie View Post
    Thanks, If I use a portafilter gauge should it read exactly 9 bar to get the ideal brewing pressure?
    Just saw the video. You didn't misinterpret it (it's just wrong).

    9 bar at the group is a guide only - the pressure will vary during an espresso pour, as the resistance and flowrate change.

    Greg Pullman's portafilter attemps to replicate flowing conditions, so that there is some pressure drop in between the OPV and the group.

    It is a better approximation of real conditions than a blind, but you are effectively calibrating the OPV/pump gauge for a single flowrate.

    Leave a comment:


  • symphonie
    replied
    Originally posted by MrJack View Post
    Completely wrong, sorry. The pressure at the gauge will be equal to atmospheric pressure (0 barg) plus the pressure drop across the valve (usually adjusted to 9 bar). The pressure at the pump discharge will be the pressure at the gauge plus the pressure drop between the gauge and the pump ; which may be 1 bar, in some circumstances (which would result in 10 barg at the pump discharge).

    Pressure can't be diverted elsewhere (but flow can).
    Thanks, If I use a portafilter gauge should it read exactly 9 bar to get the ideal brewing pressure?

    Leave a comment:


  • MrJack
    replied
    Originally posted by symphonie View Post
    According to this WLL vid on youtube, the gauge should read 10bar to get 9bar at the grouphead as the excess 1 bar will be diverted to the reservoir? happy to be corrected if I misunderstood. getting a porta filter gauge myself to adjust the pressure on my BFC junior.

    https://www.youtube.com/watch?v=torXYzDE2y0
    Completely wrong, sorry. The pressure at the gauge will be equal to atmospheric pressure (0 barg) plus the pressure drop across the valve (usually adjusted to 9 bar). The pressure at the pump discharge will be the pressure at the gauge plus the pressure drop between the gauge and the pump ; which may be 1 bar, in some circumstances (which would result in 10 barg at the pump discharge).

    Pressure can't be diverted elsewhere (but flow can).

    Leave a comment:

Working...
X