I'm trying to improve my shots further. They're good i feel, but i wondered how other people pull their lever strokes; i hoped i might pick up an improved method.

I'm really just talking about the pressure of the pull. At the moment i preinfuse to moisten the puck, then gently pull until i see drips on my bottomless pf. Then i increase the pull pressure slightly and maintain it. I'm not getting early blonding, any the shots taste great, with rich tiger's eye crema, but i often get small hints of channeling - nothing massive, but sometimes a slightly eccentric flow, sometimes two dribbles both near the centre of the basket.

I'm paying close attention to dose (accurate scales), distribution (WDT), and tamp (probably 20 pounds pressure), and i try not to break the edge seal of the puck in the basket....

Any ideas to get one central pour out of the pf basket?

make the grind slight more coarse and tamp a little harder. That should take care of it.

Ray

I've been spending more time with my 15 year old LP lately (got to - it was a wedding present from my wife, and we're about to celebrate our 15th next week ), and there are a couple things I've just done that seem to make a difference in my shot quality. The biggest improvement came with using a larger PF basket that I easily fill with 16 grams. That right there, and the espresso-making-experience with various machines that I've gained over the last 15 years has been huge.

Next, and I don't have enough data yet to feel comfortable calling it an improvement - I changed out the stock nylon piston to a brass one I got from OE. My feeling is that it will lead to greater thermal stability... all I know is the one shot I pulled after installing it this last weekend was one of the best I've ever made. Klatch's Belle never tasted better. Nutty, caramel, and hints of brandy. Amazing. I'm going to enjoy getting to know this machine all over again.

One thing I've been enjoying experimenting with this, and my other levers, is with pressure profiling. For me, that means more of a backing off on the pressure near the end of the pull. My goal is to keep the flow of espresso steady, and that requires easing up on the pressure toward the end. On my PV Lusso (spring lever), I actually gently resist the spring's force.

uyeasound wrote:Any ideas to get one central pour out of the pf basket?

Like you I have a millennium, and have done a lot of experimenting, but cant say I've found a method to reliably get an even, central, no-donut pour.

I like to updose to 18g on some blends (e.g., Black Cat), and this I think is contributing to a tendency to donuts and unevenness. I do think my pulls tend to do a little better when I use a nutating tamp. I'm most careful about getting that dose perfectly evenly distributed, level, and evenly tamped. I tamp really hard or pretty light depending on the grind (have a baratza virtuoso, and use the tamp to make up for not having fine adjustments) and cant say that harder tamps help with evenness in my case.

My technique is like yours, except I hold the lever up, and leave it there for 15 seconds, or til I see beads forming at the perimeter of the basket - whichever comes first. Then I smoothly lay into it so that the center fills in with beads. Sometimes the whole center fills in nicely, but often not. As the gloppy drops become a mini mouse tail (alas, sometimes two) I ease off as needed for a steady slow ristretto-ish shot. I'm generally easing off the pressure as the pull progresses.

Put it on a bathroom scale. As I recall, 15 pounds of pressure will get you around 9 bar at the puck. I use to raise the lever, let it infuse for about 5 seconds, pull the lever until I got one drop, then gently raise the lever, wait another 5 seconds and then pull my shot. Not a big fan of multiple lever pulls. It breaks the pucks adhesion to the portafilter and gave me sub par shots. Every time you raise the lever, you suck air back up through the portafilter and puck.

Not a big fan of multiple lever pulls. It breaks the pucks adhesion to the portafilter and gave me sub par shots. Every time you raise the lever, you suck air back up through the portafilter and puck.

I do a slight Fellini. Before I attach the portafilter, I let water enter the group (and remove air), then I drop the lever enough to close the valve and then lock in the PF. I lift the lever to resume the flow of water and when the chamber is full, I start the extraction. If I am interested in maximizing the volume of the extraction, I gently raise the lever again to replace the volume of water saturated into the puck. Since there is always some amount of compressible air at the top of the column of water, I am not convinced that a Fellini move will suck air through the puck. I think that the Fellini represents a decrease in the pressure exerted on the puck, but not a negative pressure. (This method applies to the pavoni and the commercial spring group.)

Yes, i use fellini, but no double pulls. I think the fellini move helps to fully fill the group.

Does everybody level after distributing in the basket?

I have a 51mm tamper for my pavoni, and there is a tiny clearance, possibly enough to mean the edge is less compacted than the centre, and liable to channeling. I have been experimenting with a bowl ish distribution before tamping. Meaning more coffee further away from the centre. After i have tamped it looks even and solid, but the centre is actually less compacted, and i think i'm getting reliably even single central pour from my bottomless basket.
The bowl distribution might be counteracting the slight tendancy to leave the edge (relatively) uncompacted, and hence giving even pours. But i'm still experimenting.

Thanks for that tip. I tried that a while back - was using the lid of my grinder hopper to get a concave rather than level distribution before tamping and gave up on that. I'll need to try it again more carefully.

I noticed that a couple of the 'old hands' were encouraging a coarser grind and a lighter pull. I think that helps get a more even pour, not sure I like the taste as much when I do that. However, by my calculation, given a 44mm cylinder diameter and an 11:1 lever arm advantage, I believe that 9 bar works out to 27 lbs at the end of the lever.

I do a sort of fellini when I make coffee (split shot) for my sisters, who like single-shot small breve drinks. But beware that the millenium does not benefit so much by working back and forth at the top because the cylinder does not have the vent hole above the inlet hole, it has only one hole and it's right against the lower gasket when at the top of the stroke. The advice on this thread, to pull til you see some drops then gingerly go back up and let it refill, is a good one - works for me when I want more volume.

I always WDT stir, level, thump,thump, then lightly use my 51.0 mm tamper NSEW to press down the perimeter, then thump again, then give it a leveling tamp with my thumbs feeling the basket rim and tamper shoulder, then give it a little nutating tamp, then give it a real (usually 20# - 30#) tamp. Whew! actually it's easier and quicker than it sounds. But I can't honestly say how much of this nonsense is necessary.

P.S.
One poster recommended a larger basket. On the millennium you have only one size available, and it's comparable (maybe even larger) than the large Elektra 49mm basket that many of the pre-M owners seem to be using.

homeburrero wrote:One poster recommended a larger basket. On the millennium you have only one size available, and it's comparable (maybe even larger) than the large Elektra 49mm basket that many of the pre-M owners seem to be using.

Yeah, I realized later that I should have provided additional information. The basket I use on my pre-Millenium is an Elektra 49mm in which I can easily fit 16+ grams. That's the amount of coffee I've been working with lately, and I like the results.

With the original "double" basket I have, 12 grams is the max, and that little would barely the screen. Though my technique and knowledge of espresso have dramatically improved lately (at least I'd like to think that's the case ), moving to the larger basket, and more coffee, really made a difference.