BaristaBoy E61 wrote:For me drying the shower screen after each shot is part of the cleaning process.

I keep water in the blind filter on the group. A wet screen is unlikely to be the issue.

Hi Guys,

Tried a few things:

-Preheated for 1 hour
-Flushed 5-10 seconds before 1st shot and in between shots
-Dried shower screen in between
-Tried using the 2nd grinds for 1st shot, 1st for second and 3rd for third.
-Weighed everything a few times to eliminate the scale issue.

My DF64 is a "P" version which fixed the declumper issue. I tried weighing G in and out and it doesn't seem like it is retaining much. Even if it does, I would imagine the retention should be somewhat uniform between the 3 grinds for 3 shots?

All 17.5 G to 18G VST basket Target is 30G in 32 seconds. Closing lever when I see 28G or I overshoot.

1st Shot: 30.2G in 35 seconds (too much time, did not taste this shot went too wife)
2nd Shot: 31.1G in 29 seconds (Tasted good)
3rd Shot: 29.1G in 22 seconds (stopped too early, but pulled noticeable faster than the others. Tasted more sour)

Not sure what is going on, but even with a 3rd shot, and using 2nd grind for 1st shot, findings still seem to be that it extracts faster and faster without touching my grind settings.

I attached a pic of my used puck on the 3rd shot. Doesn't seem too dry or wet. I'm starting to think that maybe 17.5G is too under filled for an 18G VST?




Not really sure what else to check here unless my tamping and WDT is too inconsistant. Using the standard ECM tamper that comes with the machine.

Before pulling the first shot, you might try a preliminary shot using a blind basket to get some flow and the pressure up to initialize the machine. Decent Espresso sells "Puck Simulator" baskets that would allow you to mimic a first shot without wasting coffee, and avoid sending you in the wrong direction for dialing in (based on a long first shot).

Consistency in WDT is also essential

Thanks for the tip. Might order one of those Puck Simulators. Is it normal though to have to go to this extent to have consistent shots?

It seems the variance in extractions is fairly large for the very small inconsistencies that could happen with my puck prep. I'm guessing my lack of experience doesn't help, but still.

No, your variation between shot #2 and #3 is too inconsistent. Generally for me, out of say 3 or 4 nearly consecutive shots, they will all be within 3-5% weight per same time unless I screwed up puck prep. And, again out of the same 3 or 4 shots, most often one will be bullseye taste and the remaining shots are maybe 2nd ring out from bullseye; close but not identical. I rack it up to dealing with differences in a product of nature, roasting, resting, bean blending, etc.

What do you mean by "Closing lever when I see 28G or I overshoot"? I just pull the espresso cup when the desired target time weight is achieved on a spring lever machine.

I'm grasping at straws now, but what is the condition of your piston seals?

And, have you tried a different beans/bean blend with different roast profile than what you're using? Again, not to beat a dead horse but I very seldom am pulling beans at 22+ days old save for especially high density, lightly roasted beans that more often than not need more rest time. I'm currently pulling a "medium" SO El Salvador honey process bean from Red Rock roasters in Albuquerque New Mexico, at 10-days and they are optimum. And light roast Ethiopian Wote Konga beans from Peregrine Coffee Roasters in Colorado also at 10-days and flows are very consistent and flavors are spot on. Having said all that your problem does seem to be more hardware related than bean related but I think we're all at the "throwing mud on the wall to see what sticks" stage.

I have been using VST baskets, along with IMS baskets, for many years. Unless you are using a darker roast (generally darker beans require a coarser grind thereby taking up more space in the basket), I find 18gVST basket takes 18g of beans day in/day out. Although the shower screen imprint looks very good/great, I'd still try 18g dose especially if the beans you are pulling are "medium" roast level or lighter.

Do you have a grouphead pressure gauge on your Synchronika? That would allow you to see how the brew chamber pressure is varying throughout the extraction and would be useful in diagnosing the cause of your marked extraction time variation. It could be due to several things that haven't been mentioned yet, such as sticking "pre-infusion" chamber spring. Other possibilities are anything that would vary the pressure in the brew chamber, such as fluctuating pump pressure or obstructions in the brew water circuit.

Of course, this presupposes that your grind and puck prep is consistent between shots.

spressomon wrote:I'm grasping at straws now, but what is the condition of your piston seals?

OP claims ECM Synchronika in profile.

As much as I detest video, in this case one of each shot into a clear cup might be revealing

^ I must be too caffeinated . Had this thread mixed up with the Profitec 800 thread...sheesh!

You could try letting the water flow without the portafilter in. Do 30 secs and measure how much water you get. Then wait 1-2 mins and do again. If the 2nd time has more water, then it may be an issue with pressure or water flow with your machine.

Fred I think this was happening to me too. I got my machine last Friday night, a week ago and pulled about 40 shots over the following couple days. It wasn't until Monday morning did I pull a really good shot, and actually consecutive good shots. What helped me was really focusing on puck prep. And I tamped the hell out of the coffee with the stock ECM tamper. I'm pulling Ethiopian single origin, so I've found success with a pre infusion until I see some nice espresso syrup emerge from the basket and after maybe 6 or 8 seconds or so I engage the pump to pull the shot (machine is plumbed in). This tastes good to me and is repeatable. But if I switch coffees I'm screwed and have to burn through a handful of shots to get something I'm happy with. That's frustrating because I like variety but then again can't be too hard since the machine is so new.

A thought that crossed my mind is have you checked for any kind of obstruction? If there was something in the line somewhere it might rotate intermittently, restricting flow only sometimes. I used to write service in a boatyard and came across this regarding fuel feed. Only certain flow rates would move the object and it would obstruct. Don't want to put an idea in your head that doesn't need to be but I simply can't think of anything else. It's either puck prep or faulting hardware for whatever reason. Best of luck and keep us updated.