Another extraction issues thread :)

[hawk87]

Hi guys, having a strange problem with by Silvia and bottomless portafilter.....

I'm getting extraction sweeping from the closest to the machine side of the portafilter towards me....not a circular formation coming together in the middle that I have normally had for the past (ever). Also noting that the furtherest away from the machine part of the portafilter doesn't pour through until 10 seconds into the shot (uneven extraction).

No channelling however, comes together in the centre no probs....but the colour/extraction is defs uneven. Coffee still taste ok, but that's why I'm here......none of us are ok with just "ok"

Have changed a lot of variables with no consistent results - no circular formation coming together in the centre.....sweeping from one side of the portafilter to the other.....

Could there be a pressure/mechanical issues with the Silvia?

Will take a vid later tonight to show. Current setup is a Mini-E grinder, with a PID'd Silvia V3. Use an OCD for the redistribution, but have tried WDT and just tapping/setting grinds with no different extraction results.

Thanks for your help or past experiences.

[kyeba]

I had this happen when I owned a Silvia, bought a new shower screen and it was sorted.

[hawk87]

Appreciate the info - can I confirm if it was the one with the recessed screw (completely flat) or protruding out (leaves a dent in the puck). Currently running a recessed one. Also was it just the screen or the diffuser as well?

Cheers!

[noonar]

I manually dose 19g in and 19g out of my mazzer mini e into a 18g VST on a pretty fine setting. I sometimes have the same flow problem as mentioned above as well as the occasional donuting, distribution is the major culprit in my case. I have not noticed any cup differences between a lopsided pull and a "normal" extraction. If I take extra time to collapse twice and add some WDT the problem goes away.

[hawk87]

I manually dose 19g in and 19g out of my mazzer mini e into a 18g VST on a pretty fine setting. I sometimes have the same flow problem as mentioned above as well as the occasional donuting, distribution is the major culprit in my case. I have not noticed any cup differences between a lopsided pull and a "normal" extraction. If I take extra time to collapse twice and add some WDT the problem goes away.

Appreciate the info - Same dosing for me too - 19 grams into an 18g VST ridge-less basket.
Will have a further play around with the redistribution etc and check the results. I feel you're right re: cup results/taste, however it just doesn't seem optimum. I also note some remnant parts of the puck on the lopsided part of the extraction.....indicator for something going wrong?

[kyeba]

Appreciate the info - can I confirm if it was the one with the recessed screw (completely flat) or protruding out (leaves a dent in the puck). Currently running a recessed one. Also was it just the screen or the diffuser as well?

Cheers!

It had the protruding screw, and existing shower screen was more form fitting to the diffuser.

The new shower screen came from coffeeparts and fit the diffuser a bit differently.

I replaced shower screen only.