Long Term Extraction Issue with La Marzocco Strada MP - Page 2

#11: Post by **Beaniac** » September 22nd, 2015, 2:16 pm

Like LukeFlynn I also see a lot of focus on the machine and not on either the grinder or the actual coffee.

But I'm probably being silly, you must have tried a different bean and grinder already right?

#12: Post by **LukeFlynn** » September 22nd, 2015, 3:22 pm

A tilted shower screen (If you put the screw in off level and strip it, or tightened too tight) can also cause weird problems like this. But I'm betting its a grinder issue.

#13: Post by **frank828** » September 22nd, 2015, 3:36 pm

first thought, coffee distribution issue.

September 22nd, 2015, 3:42 pm

OP says he's experimented with multiple methods.

Pergdistribution is my favorite if you haven't tried it, try it. Stockfleth's is generally good enough though.

I do think it would be a good idea to post a video on the entire process.

September 22nd, 2015, 4:51 pm

Are you sure the machine and/or grouphead is level? Have you checked this?

#16: Post by **bmb** » September 22nd, 2015, 5:45 pm

I had something like this and the solution was leveling the feet of the machine.
Try regulating higher (or supplement) the back feet.
Worked well for me.

#17: Post by **Terranova** » September 22nd, 2015, 6:19 pm

Beaniac wrote:Like LukeFlynn I also see a lot of focus on the machine and not on either the grinder or the actual coffee.

Pretty sure that the grinder is to blame.
Even if you redistribute and tried different distribution techniques, if something is wrong with the particle size range because of mechanical interventions (axial, radial play between cutting parts) then distribution doesn't help.
It would have been my first thought.
At least it is worth a try.

#18: Post by HB » September 22nd, 2015, 6:56 pm

canuckcoffeeguy wrote:Are you sure the machine and/or grouphead is level?

I'm skeptical that would matter. Being off-level could affect the direction the cone pours, but it wouldn't affect the initial beading. In the OP's video, the initial beading is quite uneven compared to this pour.

September 22nd, 2015, 7:11 pm

Doing a bit of pre-infusion does help slightly. But not something that should be required every time.

Agree about the EE.

boost wrote:Hmm, I'll double check my MP and see if it does that. But taste is what matters really.
Couple thing to check:
1. Is there noticeable channeling in the puck after the extraction?
2. What's the flow rate of the group head? Should be around 500mL/min. Since you go to full paddle right away if your flow rate is too high then you are more prone to channeling.
3. Try moving the paddle to lower flow/ mid position to saturate the puck first. This would make it more forgiving and really one of the advantage of MP.
Not quite related with the issue but personally I think EE is a better solution for shop, less maintenance and most shop don't really have time to modulate the paddle anyway.

September 22nd, 2015, 7:14 pm

The group heads are actually noticably out of level. I have the rear "feet" raised up with some cardboard to compensate and level it out. Again, not something I should have to do with a +$10k machine.

erics wrote:I assume this problem occurs on both groups. Make a scratch mark on the rim of the dispersion screen(s) and rotate them 180 degrees.

Insert a blind basket in your bottomless portafilter(PF) and check the level of the bottom of the PF from front to rear. Compare this to the levelness of the machine and possibly temporarily level the machine as necessary to get a more accurate reading of how the portafilter is sitting in the group(s).