La Marzocco - adjustable headspace? - Page 3

Need help with equipment usage or want to share your latest discovery?
Billc
Posts: 304
Joined: 15 years ago

#21: Post by Billc »

LM does make a thicker portafilter gasket. It is about 1mm thicker so you can increase you head space if you like. Instead of the nickel trick try inserting the basket and filling until you see an impression of the dispersion screw in the middle but no contact with the screen.
Here is a pic of what the head space looks like (cross section of the group).

One thing to try is to increase the distribution. There are 2 types of distribution. The distribution of coffee in the basket and the distribution of particle size within the coffee. Depending upon how your grinder is working the later can change. Try grinding the coffee, place it in a stainless container (or something else) and mix it up with a spoon. Then pour it into the portafilter and see if there is a difference.

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shawndo (original poster)
Posts: 1013
Joined: 14 years ago

#22: Post by shawndo (original poster) »

The other thing that turned me on to a possible headspace issue is that the screw actually touched the thermocouple in a scace device. This happened on mine and Jon K's Shot Brewer. I think the latest hypothesis is that we just have big dispersion-screen screws.

I did have some success today with just tamping harder. I think I was tamping at 10lbs or something, but did 30 today. I have to do more testing through the week. another one of those embarrassing mistakes if all this turns out to be a tamping issue.
Darmok and Jalad at Tanagra

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shawndo (original poster)
Posts: 1013
Joined: 14 years ago

#23: Post by shawndo (original poster) »

alright, I'm 3 for 3 today with no more channeling or super-puck expansion. I was just tamping without fortitude the whole time. :oops:

I think I read an odd post a while ago that suggested tamping lighter. I must have tried it and liked the results and immediately thought I was doing it all wrong and now i have it all figured out!
But then some other variable probably changed which back-pedaled my espresso. Oh well, the journey continues....
Darmok and Jalad at Tanagra

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