Grind difference between two E61 espresso machines...

#1: Post by **ertech** » October 9th, 2019, 8:55 pm

the Isomac millennium I am trying to dial in is doing something weird
I adjusted the blind pressure to 10bars with Eric's pressure gauge on the head and when I make coffee it goes down to 9 bar. The my other machine an original E61 Faema is at to 9 bars .
Now for the weird part.
If I grind and tamp the same way that I do on Faema with the isomac the coffee comes out to runny on the isomac . I need to grind more fine to get a good coffee . Is this normal or all E61 should react the same .
Thanks

#2: Post by **lsun22** » October 10th, 2019, 3:39 am

yes it's normal. always will be variations between different machines, and even the same model machines since even the slightest change will impact. while you think the pressure may be 9 bar, they aren't exactly 9 bar and 9 bar. and 9 bar vs 9.01 bar will cause a difference in flow rate.

#3: Post by **randomorbit** » October 10th, 2019, 12:13 pm

I'm assuming the Original e61 Faema has a rotary pump and the Isomac has a vibe pump? Not sure about that, but if so I'd think that would make a huge difference in how the machine behaves.

#4: Post by **mohninme** » October 10th, 2019, 12:35 pm

In your case, I see several possible reasons, the first four being machine specific. I probably missed something too.

water debit/flow rate

head space

water temp

OPV/pump pressure set point

using the same basket for both tests?

consistency of puck prep

#5: Post by **JayBeck** » October 10th, 2019, 1:06 pm

randomorbit wrote:I'm assuming the Original e61 Faema has a rotary pump and the Isomac has a vibe pump? Not sure about that, but if so I'd think that would make a huge difference in how the machine behaves.

This is it. Different water debit means different rate of infusion means different pour times with same grind.

#6: Post by **another_jim** » October 10th, 2019, 1:54 pm

In addition, the groups are not identical, and their parts are not interchangeable. There are many different manufacturers of E61 groups, and at least three slightly different designs.

#7: Post by **Randy G.** » October 10th, 2019, 2:22 pm

re. The original E-61 Faema - Did you use Eric's pressure gauge to set that machine as well? If not then it could also be a matter of the pressure gauge on that machine reading a bit differently from Eric's gauge.

October 10th, 2019, 5:32 pm

Yes my original Faema has rotary pump set to 9 bar blind filter
The isomac with vibe pump set to 10 bar with blind both set with Eric pressure gage
Same portafilter
The isomac need a finer grind to get the same 25-30 sec