Inconsistent shots

[worthy1]

Yeh its still pretty inconsistent. A good grind in the morning might choke the machine at lunch or afternoon and that same grind at the same time the next day might do the same or even be too fast.

I bumped it up to 2.1grind setting and the machine choked, i put it to 2.15 and it was too fast so i used the same setting and tamped harder and it was fater then the shot before it! This morning i dropped it back to 2.1 (same grind it choked on the day before) and got slightly too fast. Tamped harder the next shot and i got the exact same recipe that i considered near perfect the other day (14.g, 30 sec, 29.5g out), ripper i thought until i tasted it and it was bitter.

Just weird how it can change so easily, the only thing i can think of is the grinder. If its not grinding consistent on the settings then it is going to keep changing the shots. I am waiting on new burrs so will see if that helps otherwise i may look into the Niche Zero, just dont want to spend the money if the problem is somewhere else. Also have a thermometer sensor coming for the group head that will help me ensure i am getting my temps where they need to be.

[level3ninja]

If anything it would normally speed up the flow a bit. Is it just the one time it's changed dramatically over day to the next and now it's pretty consistent day to day, or is it still changing a lot?

[worthy1]

Gotcha, what effect would not doing that properly have? i would have thought it would just not be as 'fresh' not lowering the flow

[level3ninja]

I purge the grinder by giving it a shake, since i half fill the hopper i cant exactly purge without grinding more beans?

Purging the grinder requires running the grinder. Even though some comes out when you shake it there are still stale beans between the burrs and inside the grinder, you're only shaking out what's in the spout. Purging means running it for a few seconds and throwing out what comes out during that time.

[worthy1]

Thanks for that, I do think it has something to do with a difference in the morning and afternoon like you mention. I purge the grinder by giving it a shake, since i half fill the hopper i cant exactly purge without grinding more beans? I have been thinking about getting a Niche Zero but i do like putting beans in the hopper every few days rather then each time i want a coffee. Potentially the beans were too young although they were 4-5 days.

[rubixcube101]

When I was a newbie starting out on a more sophisticated machine and grinder (versus the breville) there were a few things that took me a bit to figure out which was affecting the shots. The most significant was

1. making sure to purge the grinder

2. adjust the grind to suit the temperature in the morning. Where I live the temperature outside and inside varied by a few degrees every morning meaning that everyday was an exercise in adjusting the grind to get the perfect shot - I got used to it after sometime to watch for the rate that the beans were coming out of the grinder and instinctively knowing based on how the temperature felt how many notches to adjust the grind.

3. Different beans and roasts need different recipes and grind settings to get the shot out to perfection. This takes time to learn your equipment and how to adjust.

[level3ninja]

What pressure are you getting with a blind filter?

[worthy1]

Yes although i dont do what i have read some do with getting a brush up there or anything. Surelly some left over grinds wouldnt cut the flow in half or less then in some attempts? I also make two cups one after the other at times and there can be a big variance in those and thats without a purge but the grind is less then 5mins apart.

[level3ninja]

Do you purge your grinder before filling the portafilter?

[worthy1]

So again at a loss. Let it warmup again and tested the water that is sputtering and steaming out and it is 89 degrees. So I let it warmup again after that and pulled another shot with the same recipe again. This time 14g out at 35sec. Why the hell is it this inconsistent. This would have been as hot as the machine was (possibly even hotter) yesterday when I got a perfect delicious shot. I'm really at a loss here

[worthy1]

The machine is about 6 years old (unsure of exact date as purchased it second hand). I did adjust the pressure stat to turn it down from 1.4/5 bar to 1.1 which does help it not get as hot but after a 30min warmup the first cooling flush is definitely sputtering and steaming, second flush still a little.

I just tried it again after a longer warmup as I think that was the issue this morning. Although not as slow it still was 39 sec for only 24.8 out. I decided to test the temp of the water straight after so pulled a shot of water with not portafilter and it was 87degrease. Assuming it would be a little colder due to just pulling the espresso shot. It seems potentially temp is the cause but am at a loss as to how to know its right and how to get it consistent. Potentially the gauge on the group head? I don't want to have to pull a shot of water each time and check the temp of it and of course that will have an effect of the temp of the next shot anyway.

[noidle22]

How old is the machine? The older ones, mostly grey imports, massively overheat the group. There was no thermosyphon restictor installed in most of them so unless it's a newer model or has already been through a competent workshop for adjustment, chances are it's overheating.

An overheated group will give unpredictable results. After it's initially warmed up for 20-30 minutes, run the group with no handle in place for about 10 seconds. Leave the machine sit idle for 2-3 minutes then activate the group again. Is the water sputtering and steaming when it's coming out? If so, overheating is a problem.

My most recent Splendor, I ran a 250ml cooling flush yet the lowest I could get the brew temp was 96C. After installing a restrictor, this came down to a reliable 92.5-93C with no cooling flush.

[worthy1]

Hmm, that could be it then as i adjusted the time the machine turns on (on a smart switch) since im working from home and waking up a bit later, it definitely wasn't as steamy when doing my usual cooling flush. Temp is one thing i struggle with and maybe the cause of so much trouble for me, i am thinking of getting one of the Temp gauges that can screw into the E61 to help.

[level3ninja]

The higher the temperature, the faster extraction will happen. The faster extraction happens, the faster the flow resistance of the puck goes down and flow increases. Temperature will have a significant effect on overall shot time.

[worthy1]

I did think of the temperature but figured the flow of water should be the same through the grinds regardless of temperature? or does hotter water flow through at a quicker rate?

The beans are a Medium although definitely hit the darker end of medium of these ones unfortunately.