cannonfodder wrote:Interesting, part of the reason I ask is because I have been having fits pulling decent shots. I have just been attributing that to the handle side of the portafilter and having to adjust to a new machine. I can pull a pretty darn good shot from my Isomac and my lever but this machine is in a different class.
When I rebuilt the groups, one of the dispersion disks had a crack in it so I ordered a new one. When I received the new disk I was surprised at how much smaller the openings around the disk were. I attributed that to years of use eroding the brass. I got to thinking, and wondering if the group jets had suffered similar erosion over time. Jets are cheap, under $2, so I ordered a new one for the sake of trying along with a couple of ridge-less LM baskets. I am assuming that the new jet would reduce the flow rate provided the old one has opened up over time?
People play with jet sizes. 0.6mm seems to be popular with obsessive artisan baristas (which is what I aspire to be)!
I'm told 0.6mm is also the size orifice used in the LM GS-3, and the GS-3 has an pretty low water debit around 60ml/10 sec. It has a reputation as an easier machine to pull shots on, and the low water debit is one important factor, I believe. Along with exceptionally good water dispersion in the group, great temp stability, stainless brew path, etc, etc....