Puck Question - won't knock out cleanly

[Lukemc]

Hey all

Quick question regarding pucks as I can't figure out whats going on with mine.

Ive gone from using a strega (which i had no such issues with), to using a BES900 daily, i roast my own beans and use them from 7-21 days usually.

I'm getting nice extractions from the breville, tending to run slightly longer than 30 seconds, maybe 35-40 but very tasty.

My issue is i cannot get a clean knock out on the puck, it looks great when removed from the group head, slight imprint of shower screen etc but knocks out in bits and leaves 1/3 of the puck stuck all over the sides and bottom of the basket. Ive tried the stock double and my precision baskets plus a VST and all are much the same.

I dose 18 (and have tried 19/20/21) grams in my precision double normally. the coffee is great but having to physically wash the portafilter and dry it between coffees is bugging me!

Any advice? Comments? is it technique based do you think or is there some issue with the machines operation.

As an aside I'm gonna try to grab some beans from a local roaster just to see if this makes any difference.

[Yelta]

Morning Luke.

This made me prick my ears, "it looks great when removed from the group head, slight imprint of shower screen" could it be that your over dosing? over dosed pucks sticking to the screen do make a real mess.

Are you aware of the five cent piece test to help establish your dose?

[Lukemc]

Puck Question - won't knock out cleanly

Yeah mate have done the 5 cent test. As far as I can tell I'm not overdosing but I'll double check when I get home. Thanks

Ps I got an instant email notification of your post! Happy days

[Steve82]

Hey Luke,

I never had much consistency using the EP double on that machine.

Try the stock double and dose 17g , finer grind, 30sec+ shot time for 55 to 60% brew ratio.
Other than that 18g VST all the way same same thing slightly finer grind.

[Yelta]

Is any of the puck adhering to the shower screen?

[Lukemc]

I'll switch back again Steve and try but I did have the same issues. I've never had an issue with my precision baskets and I've used them now on three or four machines.

No Yelta none sticks. To my eye it looks like a good puck until I try to knock it out.

[Yelta]

Are your baskets ridged or ridgeless?

Do you knock the puck out as soon as youv'e pulled the shot ? Iv'e noticed pucks that are left to bake with the machine on for a while are decidedly more difficult to knock out, they often leave quite a bit of residue in the basket.

[Steve82]

Prob more to my point, that my experience over time was that 18g dose was the max and that 16 to 17g dose performed much better. But yes tastes / roasts vary.

A good experiment to run, try extracting a shot way longer than you normally would, until it starts to go translucent, then knock out the puck, I bet it comes out clean as a whistle.

If your extracting shorter from higher doses there will still be lots left in the coffee to " stick around "

[Lukemc]

Yep knock it out straight away Yelta.

Ill give that a go steve and see how i go, cheers

Ill also repeat the 5cent test and see how i go at 18 and at a lower dose

[Lukemc]

Are your baskets ridged or ridgeless?

Do you knock the puck out as soon as youv'e pulled the shot ? Iv'e noticed pucks that are left to bake with the machine on for a while are decidedly more difficult to knock out, they often leave quite a bit of residue in the basket.

Ridgeless had to check to make sure

[Lukemc]

16 gram dose has to be ground so fine that the 5 cent coin makes no imprint at all, shot tastes nice still, i let it run for 60 seconds (pulled the cup after 35). Very watery puck and broke up and sloppy when trying to knock out.

Will work my way back up towards 18 grams and see how i go.

[Barry_Duncan]

I usually use about 14g in the single basket. The puck usually comes out clean but I wash and wipe the basket between shots to remove oils etc. as cleanliness is next to godliness.

Barry

[Lukemc]

How much do you use in the double Barry? I might go back to the stock basket until I can sort it out.

[Lukemc]

I may have been under dosing........ Went slightly coarser and dosed higher, didn't weight just went back to basics, fill, collapse, refil, distribute, tamp....... 5 cent test, perfect, pulled shot good, banged out a clean puck........ How did I not go there weeks ago!!

Thanks for being a sounding board guys and for the suggestions.

As usual, back to basics instead of over thinking things like I often do

[Barry_Duncan]

I only use the doubly basket when making coffee for two.

It has been said that a single shot is made with 7g and a double with 14g. However the Breville Dual Boiler baskets when at the ideal capacity hold more like 14g in the single and 21g in the double.

Many people say to throw away the single and only use the double. I disagree and find that with the correct grind, dose and tamp great coffee can be made with the single. I always go naked with the single so that any channelling will show up.

Channelling through the puck gives an uneven, weak extraction. A naked or bottomless portafilter does not prevent channelling but lets you see when it happens.

Barry