Small single hole in puck

#1: Post by **Leva-rage** » August 7th, 2022, 4:46 pm

Hi,
I have an older ECM Giotto HX machine with E61(I think similar to the newer Rocket Giotto).

I don't have a wdt, leveling or tamping device, do puck prep manually. My extraction times are between 25-30 sec, and the puck is usually 'dry' after I have pulled the shot. Sometimes the puck surface has a small single hole in it, other times, the surface doesn't show any holes.
This photo shows the small hole 1/3 of the way down from the top of the portafilter, almost at 12 o'clock

Any suggestions what I am doing improperly?

Thanks,
Bill

#2: Post by **Jeff** » August 7th, 2022, 6:01 pm

Potentially just trying to read more meaning into the puck than is there.

When the exhaust valve opens, there's a strong rush of water which can do all kinds of things.

While I'm not sure about "correct extraction", here's one view of what it might look like

#3: Post by **yakster** » August 7th, 2022, 6:30 pm

Check and clean your shower screen if necessary.

#4: Post by **Pressino** » August 7th, 2022, 9:24 pm

I think Jeff nailed it...it's the turbulence created when the exhaust valve opens at the end of extraction. You can see this very clearly in the video. Bottom line, don't worry about what the top of the puck looks like when you remove the PF. The best way to visually follow an extraction is with a bottomless PF, and the ultimate test is how the coffee tastes in the cup. I've had great tasting shots from pucks that look like coffee grounds soup...

August 7th, 2022, 10:59 pm

Thanks, that is reassuring to know where the search for perfection may cause one to chase the wrong thing.