Hi All,

I have a new Lucca M58 and am battling with a nasty issue...

I am using the bottomless portafilter that came with the Lucca. I am using a Rocky grinder (plan on upgrading soon) and am getting pretty nice shots, good crema and the taste is great. What I am struggling with is the extraction itself. Most of the pour comes out and enters the shot glass nicely, but I quite often also get one or two angled projection streams of coffee that goes sideways, missing the shot glass, it lands up hitting the back of the machine and even the kitchen floor. When I see this happening I have to hold the shot glass right up to the bottom of the bottomless portafilter.

Not happy with this obviously. I have purchased a scale but have not started using it yet. What do you think the issue here is: too much coffee or being too heavy handed with the damper, or ??? I like the look of the extraction of the bottomless portafilter when it performs well, but so far I am not getting consistent results due to this issue.

Thanks for any pointer here...

This is called channeling; there are a number of causes for it. Tamping too hard is one cause, but not necessarily the cause that is affecting you. The Rocky isn't necessarily at fault either, but it may be misaligned which could be also be a cause of channeling. Search these forums for channeling, nutation, WDT, and read the Espresso 101 tutorial here for some tips for eliminating channeling.

Personally I'd try WDT first and making sure you're tamping is level.

Thanks, I will try some reading soon. I am just about to unbox a new scale and I hope that will add some level of consistency.

By the way what does WDT stand for?

Weiss Distribution Technique
Improve your Espresso with Weiss Distribution Technique

As mentioned grinder, distribution, and tamp are factors. I will add that the coffee you use, the type, but more importantly freshness has a big effect. You can have perfect basket prep and still get channeling and spritzes with stale coffee.

PhotoMax wrote:Thanks, I will try some reading soon. I am just about to unbox a new scale and I hope that will add some level of consistency.

By the way what does WDT stand for?

It's a fancy term for using an extended paper-clip to stir the grounds around in the portafilter to break up any clumps while more evenly distributing them around the basket.

Also like the person above me said - make sure your beans are 10 days post roast or less. Old beans will make a mess.

Keep in mind that the purpose of the bottomless portafilter is to show you that you are having those spritzes at all.
I think it was originally conceived as a diagnostic tool so that we could really see/understand what was going on in the puck during the extraction.

If you were using a regular portafilter you would not see that there are some errors in your prep.
Sorta like sweeping the dirt under the rug ))

I'm guessing when you upgrade from the Rocky that it will get better, but also hopefully by then you will have worked on ways to eliminate the causes of the spritzes.

Thanks Guys...

I will start using the scale. I Just opened it.

I just made a shot and it turned out nicely. This time I spent a little more careful effort rotating the filter while grinding the coffee in my Rocky. I have the Rocky set pretty fine at around 5 or so (1-40 settings). The coffee is fresh, some fancy stuff from New Guinea. I think initially I was guilty of cramming a tiny bit extra coffee into the portafilter. I will stop doing that; the scale should help. I think my tamping is decent, I have been using the same muscle memory pressure for years while using my old Silvia. I timed the extraction and it took about 38 seconds. Pretty nice cup.

Be interesting to see if I maintain any consistency. But I do plan on upgrading the grinder. I have a 19" height limit (my 1st thread on this is on the buying advice section of this forum). Right now I am leaning to the more-than-what-I-want-to-spend MAHLKONIG K30 VARIO...

I'm on my fourth grinder - had I just bought a K30 to begin with I would have saved hundreds of dollars and enjoyed years of better espresso. Go for it.

Here is a bottomless portafilter post from one of the people I respect most on this site. It was made on the lever forum, but it applies to all machines:

Bottomless portafilters: Some thoughts