just the other day I was wondering if anyone ever seriously tried/investigated making small holes in the top of the puck after tamping.
Of course I tried and did not come up with anything conclusive yet, so I still wonder....did anyone do this, is there any info on this?

I imagine it may help finding the water under pressure a couple of points of entry, MAYBE making channeling less...but I may well be thinking too much of it, so I wonder and keep playing in a really non scientific way, pricking away with the tips of the micro surgery tweezers I use for WDT.

Look up PorcuPress, SWDesigns.

thanks, always great to see that a thought that crossed my mind in a split second appears to have some value

I'm curious about the theory... If water will always take the path of least resistance, shouldn't the goal be to minimize those paths as much as possible? What would be the purpose of creating weak paths, knowing that the water will favor those pathways, potentially leaving the rest of the grinds less extracted?

The prevalent theory is that, for users that already have excellent puck prep, working with finely ground, lighter roasts, that it helps quickly and evenly saturate the puck. That's the theory, at least.

jdrobison wrote:I'm curious about the theory... If water will always take the path of least resistance, shouldn't the goal be to minimize those paths as much as possible? What would be the purpose of creating weak paths, knowing that the water will favor those pathways, potentially leaving the rest of the grinds less extracted?

I agree!! But that's just my opinion. Again homogeneous puck prep is the goal, along with a group head that supplies a shower of water evenly over the puck is key at controllable pressures...or I'm I asking for too much?!

I get that there will be weaker pathways for the water to find. Sure, ideally we want all pathways to be the same - nice and even - but there's no way. But it seems to me that purposely creating 100 guaranteed weaker pathways is the opposite of what I want to achieve. I've tried a device that does that and haven't seen the benefit. I don't have a refractometer so not measuring the results but I haven't found that it helps with channeling or better tasting extractions.

I am, however, using the BPlus shower screen and seeing a reduction in channeling and very consistent shots.

Homogeneous channeling? As N -> infinity it will be homogeneous. Maybe 100+ channels is a better approximation than a random weakness that's hard to avoid with certain types of coffee.

I dunno.

Using the needles was mentioned here:

Puck prep study

jdrobison wrote:I'm curious about the theory... If water will always take the path of least resistance, shouldn't the goal be to minimize those paths as much as possible? What would be the purpose of creating weak paths, knowing that the water will favor those pathways, potentially leaving the rest of the grinds less extracted?

I read somewhere there will be channeling no matter what. The needles facilitate the bloom (I think it might be designed to work with Previn fusion), so as the coffee blooms / swells the needle holes are closed. I think the theory is that the advantage is wetting the puck more thoroughly/uniformly.