SEMIJim wrote:I couldn't figure out what you meant by this until I started reading reviews of a bottomless PF candidate on Amazon and read complaints from some about them spraying coffee all over creation. It would never have occurred to me that could or would happen. Hmmm...

It looks like the Amazon complaints are about coffee spraying out of the top of the portafilter - so a portafilter that doesn't fit the group correctly, or a worn group gasket, or a basket with too pronounced a lip.

Another_Jim is talking about spritzing out of the holes in the bottom of the basket - which happens due to channeling, i.e., due to the user's puck preparation (which is what one is trying to improve).

This is a great topic I've wondered about myself. It seems like the question starts with channeling and its effect the shot. It stands to reason that channeling would affect taste and shot quality, making it thin and weak. Yet I wonder whether the visual feedback provided by a bottomless PF is that much more useful than simply tasting the output. I've avoided bottomless PFs because they seem to introduce more complexity to the brewing process. I can see how, for some (or many) the extra complexity and the gratification of the impressive visual result can enhance their brewing experience. But for me the extra complexity would need to be justified by a dramatic improvement in taste that's difficult to achieve without the bottomless. I'm not sure that is the case though.

It's not just massive channeling that a bottomless can reveal, but other inconsistencies in puck prep. My espresso has improved in both consistency and quality through the use of a bottomless PF, especially coupled with using cell-phone video to replay and see, in painful slow-motion, all the things my eye missed while it was pouring.

Ignorance is bliss definitely applies to puck prep. Slow motion video seems especially masochistic but its like training for anything. No pain, no gain. The idea is to isolate the things that do and don't work and narrow them down to a repeatable routine that gets easier over time as you develop muscle memory.

I'm dealing with a bag of coffee right now that required the bottomless for me to understand. I have pretty good puck prep but this bag started randomly developing dead spots and inconsistent flow on day 2 and 3 after opening. By day 4 it was having fits.

I know I'm doing the exact same things to it so it became pretty obvious that it was stale coffee. This particular roaster refuses to use roast dates on their bags to spite charging $24/340g.The way I worked around it was to change baskets to the E&B and spraying the dry tamped puck which made the extractions more even and the coffee bareable.

I would have not known any of this if I was not tuned into a routine that gives me repeatable results with a wide range of coffees.

10

You have no idea what your distribution is like if you don't have one. You might get a clue that something tastes off with a spouted. But there's no way to tell whether you're habitually doing something that leaves one area of the puck subject to channeling and not others, for example. And as others mentioned, You can clean it so easily between shots. This should be purchased at the outset for any person just getting into this.

As a new guy to espresso I let myself go down a bad path starting off with a bottomless. I got to grinding to fine and taking to long to pull shots all in the pursuit of good looking shot. Once I put the spout in the bottom of my flair basket, and got myself into the ballpark of a simple 30 second 2:1 shot, then I took the spout off, and was able to start fine tuning my puck prep. Happy to report that since doing this things are tasting much better, and I'm not having to clean up spurt messes. If I get a wildly different bean (like going from light to dark roast) I'll put the spout back on while I dial in my grinder, then go back to bottomless once I know I'm in the ballpark.

Wild. The opposite of the conventional wisdom. But if it works for you, then keep at it

I think it's an essential tool, but you don't have to use it all the time. I would definitely use it while learning to pull good shots (which, for me, took years!), for dialing in and for troubleshooting. Once you get a coffee dialed in, you can use the spouted PF if you prefer.

You can find a number of posts here from me talking about how I finally stopped obsessing about how my shots looked and went back to using the spouted PF. But later I went back to the bottomless and pretty much use it all the time now. Every now and then I pull a shot with the spouted to see if it tastes different. Sometimes yes, sometimes, no.

It's true that the bottomless is much easier to clean, which is one reason I went back to it. But the main reason was because I do flow and pressure profiling. The bottomless gives you a real time window on what's happening at the bottom of the puck, not only in terms of how good your distribution was, but also how the extraction is progressing. The spouted PF hides this information for a while. For example, when I set the grind and preinfusion flow rate, I need to know how long it takes before the first drops appear on the bottom of the basket, and whether they take forever to drip, drip slowly, or gush out.

You should definitely get a bottomless. It's very helpful for daily use and sometimes crucial for troubleshooting.

I don't know if this has been mentioned but another (minor) advantage is that the portafilter never gets dirty - just the basket!