In addition to the "learning tool" advantage, there's a simple but oft overlooked practical advantage to using a naked pf, at least for those of us who like milk drinks... you can pull into a taller cup.

HB wrote:Matthew, I'm curious, if you don't mind answering: What problems did it reveal, how did you fix them, and how was the espresso improved?

With a regular PF, the flow of espresso is all directed into a nice looking stream by the spout -no matter how uneven the extraction or channeled and cracked your puck is. With the naked PF, if you have a channel in the puck (a weakness thru which water can exit) you'll see it right away as espresso side squirts out the bottom. If you don't tamp and dose evenly, or if your coffee has clumps in it that you don't break up, the extraction will appear lopsided and uneven exiting the bottom rather than nicely centered.

I just assumed I was doing these things correctly but the naked PF showed me I was not! Once i started using it, I could see my extractions were lopsided and I had little side squirters making a mess on my counter. A regular PF hides this from you. The naked PF forced me to focus more on my grind, dose, distribution, and tamp. The naked PF also showed me more clearly the importance of the grinder; being able to grind finely at the expense of clumping the coffee is a poor trade off (this is where Rocky comes up a bit short, IMO). But the process was frustrating and it had to be done before 7 am since that's when I drink most of my espresso. It also wasn't that quick. At the end of the process I think my espresso is better than it was before but it took a lot of reading and experimenting to get there.

mborkow wrote:But the process was frustrating and it had to be done before 7 am since that's when I drink most of my espresso. It also wasn't that quick. At the end of the process I think my espresso is better than it was before but it took a lot of reading and experimenting to get there.

There's the rub being a Home-Barista. Because you may only have yourself and a few others as "customers" the opportunity for practice is pretty limited and the pace of progress is much slower then if your banging out drinks all day for a steady stream of customers. You do have the luxury of making your espresso routine as streamlined or as complex as you desire and add all sorts of measurements and rituals to making coffee that may not be practical in a production environment.

This is one reason I like singles and Saturdays, being able to spend some time and drink more shots while working on the espresso machine.

As for clearance, it would be nice to go bottomless on the La Peppina. I have to pull the drip tray grate off and put my Pavoni cup in at an angle to make long blacks for the Wife, something I don't need to concern myself with on the Gaggia Factory because it has much better clearance without the spouts (I think it would have more clearance if I still had a spouted portafilter too). Too bad I'd have to loose the handle if I went bottomless because it attaches to the integrated spouts below the basket.

Just got a bottomless portafilter for my CMA Lever machine.
Since I don't have all the cowlings and whatnot on the machine at the moment, you can watch the lever and the extraction at the same time:
I just love the quiet contemplation of a lever pull.

Bottomless portafilter is bit like being naked. Reveals more than you want to see sometimes.
Find it an essential aid in dealing with some deficiencies. Plus clean up is quicker and easier.

allon wrote:I just love the quiet contemplation of a lever pull.

It's a beautiful thing ... a sight to behold

narc wrote:Reveals more than you want to see sometimes..

Ain't that the truth. While the pull wasn't perfect, it was still damn good.

I think you need to be careful for the bottomless portafilter not to be your only portafilter. Espresso often tastes better with spouts, lever or no lever. Actually - that's derived wisdom, I think the reality is that bottomed but not necessarily spouted portafilters give different extractions, so bean choice may be affected by PF choice, as may brew temp etc.

However, they are a fantastic diagnosis tool for a lever pull - pull without, then pull with - it's well worth understanding the mechanics of the pre-infusion and infusion through the shot. As lever pulls are that much more user-affected, the naked pf is that much more of an effective training and diagnosis tool.

Spouts are nothing a monkey wrench can't handle.

...or a hammer.

Simple answer yes!
1) it's brutally honest, will highlight uneven tamping, donut problems, spritzes, dead spots/distribution problems.
2) instrumental in helping you fine tune your grind, dose and tamp.
3) I find preheating the porta filter to be much less important with the bottomless setup. The basket itself is such a small thin mass of metal plus no bottom = No massive chromed mass of brass a bottomed portafilter has to rob precious heat from/shock your shot.

Since switching over my shots have improved immeasurably. Of course I'm fairly new so I suspect the bottomless portafilter is helping me more than it would a pro with hundreds of pulls.

4) much easier to clean up.
5) last and most importantly... It is sexier than words can describe to watch that beautiful tiger striping in action.

Okay, a contrarian post. No howls please!

Advantages of a stock portafilter:
- Helps cool the group more effectively than bottomless with more metal mass
- No need to fuss with another PF or OE heat sink first. Just plug it in to adjust temp and pull the shot for a more efficient routine
- Dual spouts allow split shots (and yes, they can also get in the way)
- Less hassle at 6 a.m.

Am I a true believer in the contrarian view? No! I use one with my Isomac Amica, where it has refined my technique and I transfer that technique to my lever machines. Owning several levers makes equipping each of them with a bottomless PF costly because I would still need something additional for cooling the group.*

Bottom line: I think they're helpful but not essential. Even if I had them for my Pavoni machines, for efficiency I would only use them sometimes.

* Added later: I've gone to the bottomless portafilter on my La Pavoni pre-Millennium dual switch machine, and it's better. See below.