Could it be that your grind finally gets saturated at the end, swells, and seals the puck allowing pressure to build? For whatever reason, what you both describe doesn't seem abnormal to me.
Without question, if your grind is too coarse the pressure can't build so the 4-5 bar is normal. Try pulling a shot with no PF in place and see how high pressure gets then! :) If your machine builds/holds pressure against a blind PF, you're chasing a problem that probably doesn't exist. b Sent from my 8-track deck On Apr 8, 2012, at 11:40, guido <[email protected]> wrote: > hello jj, > > i just experienced the same thing that you described. i went coarser on the > grind, the pressure started to go up after 8 seconds or so, only to stall > around 5 bar. then, around 20 seconds in the pour, blonding started to occur > along with some channelling, and at this point the pressure strangely went up > to some point between 8.5 and 9 bar. > > strange. > > happy easter everyone, > guido. > >> approx 60 seconds. Brew pressure measured at 9 Bar. I then made the >> grind increasingly more coarse. The dose size (14 grams) would remain >> the same. My hope was that I would be able to reduce the shot time >> and maintain the brew pressure. What ended up happening was that the >> shots times did decrease to a point and brew pressure remained >> consistant. Then mysteriously brew pressures would only climb to 4 or >> 5 Bar after pre infusion. Towards the end of the shot (at the point >> where blonding has occurred and the fluid has changed to a clear >> state) the brew pressure shoots up to 9 Bar (I realize that I am >> allowing the shot to continue too long once it has reached this >> stage). > > -- > You received this message because you are subscribed to the Google Groups > "Brewtus" group. > To post to this group, send email to [email protected]. > To unsubscribe from this group, send email to > [email protected]. > For more options, visit this group at > http://groups.google.com/group/brewtus?hl=en. > -- You received this message because you are subscribed to the Google Groups "Brewtus" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/brewtus?hl=en.
