Main Problem Solved

Tomaso Tarini at Zacconi answered my query about the odd behavior with putting pressure on the lever and having something give way and spill grounds into the cup. Of course it wasn't the piston gaskets. The portafilter gasket that was installed in my machine was the wrong kind, an o-ring instead of a flat gasket. I dropped by Christopher Cara's shop today and picked up the correct gasket and installed it. When installing it I used a short, stubby screwdriver because it fits very tightly and the outer edges must be tucked to get it fully seated. Christopher had advised me about this. Now I can put pressure on a pull without anything giving way and I can get crema. The first shots I pulled this way were nicely layered too.



Tomaso also suggested that I put a spacer on the piston rod to limit the travel so that when the handle is raised it stops in the middle of the hole inside the cylinder. Christopher didn't have one of those spacers in stock so I asked him to order one. Meanwhile I'll be careful to not raise the lever beyond what's needed for preinfusion.

So, I'm very happy to report this Baby is a viable manual lever and one of high quality. Thanks to Tomaso the main issue is solved. The short pull doesn't seem to be an issue because coffee can infuse into the coffee cake. Now I will enjoy dialing in dose and grind for this machine.

Well, glad that's settled.
But I wonder why Cara sent me that o-ring?
If he'd sent me the proper gaskets, those lovely shots would be MINE!!!

Frustration is the worst part, when you KNOW you're doing things correctly, and no matter, the results disappoint.

Keep us posted on how the mod for the lever level works.

Lost in Translation?

I can only speculate that since Christopher only drinks a traditional dark roast with robusta in it, you easily get crema and a less dense shot is better. Therefore he provides the o-rings because they're easier to install. I had to work diligently to make sure the gasket was fully snugged into place. If you grind coarse with that setup you'll optimize his coffee but not the lighter arabica roasts we are used to drinking. My Lady Duchessa is a study in this. It's obviously a high quality machine with a pretty weak spring. It optimizes a dark roast and you would get crema with robusta in the blend. I've added a booster spring to adjust it to the coffees I like. Now it pulls more like an Elektra Microcasa a Leva with a standard spring.

I tried some of the Baby Lussos in Christopher's shop and the piston action was a bit firm but smoother than mine. Now I'm thinking of removing the Teflon tape from under the gaskets to see if the standard piston gaskets are good as-is and yield a pleasant, smooth feel that still provides enough of a seal.

Sometimes tenacity succeeds where reasoning isn't sufficiently clear. I should have reasoned that there's no way coffee grounds can leak through a shower screen. They had to be leaking through the portafilter gasket, which was where pressure was releasing.

Baby Has Sniffles

Well Rob, if it were only so easy. Read and and you'll see why Christopher thought it a better to ship an o-ring.

After my last post, I was shutting down the Baby and did a flush to clear the shower screen, which popped out. It's one of those stamped metal screens with edges that look like this.



So I decided to take the piston out, reseat the piston gaskets without PTFE tape underneath so there would be a smoother feel to the pull, and if I could find the o-rings I thought I had create a spacer as Tomaso had suggested. I was in luck for the o-rings.



But the shower screen was a struggle at first and re-seating the portafilter gasket created a nose drip. I thought it might help to bend the tabs on the shower screen outward. Since this is stamped metal it holds its shape. I was able to bend them out a bit but found the edges did not snug under the portafilter gasket when it was installed. So I went the other way and bent the tabs inward a bit as this shower screen is held on by the tabs, not the gasket.

The gasket posed a problem, though. When the Baby came up to pressure there were drips all around the shower screen. These were not through the screen so the culprit was the piston gasket, I believe. When I was trying to snug it into place, it gets a bit bendy, so I crimped the outer edges into place using a screwdriver blade. The portafilter gasket is made of soft rubber which shredded in places on the outer edge. Very frustrating. I've ordered another through OE.

Yeppers, those gasket were unexpectedly soft, much more so than the Cremina's if memory serves.
Baby's being naughty!

It's not the piston gaskets but the portafilter gasket that's causing troubles now. It's dripping on the inside next to the shower screen.

I'm really puzzled with this attempt to service what should be a working machine. In trying to fix the nose drip I changed out the soft rubber squared white gasket for a standard gasket that size from Orphan Espresso. It seems to fill the space well and the portafilter locks in, or so it seems. I've replaced the stock gaskets, wrapped them with Teflon tape underneath to snug them out and the nose drips stopped. The replacement gaskets had only a tiny nick or two at the edge, so I thought that was the problem. The gaskets were tight enough I had to work hard to get them in but did this very carefully to avoid any further tears. But then again today I tried a moderate pull and the gaskets slipped again, spraying coffee into the cup. Coffee also got past the piston gaskets and washed into the boiler. I've found another thread on here where someone had the same problems. Here's a best guess on that thread:

mikekarr wrote:I've tried pumping the lever a bit and I hear a squishing sound before the first drops come out.... It really feels like there is air in the piston. The water is getting a little dirty too, so clearly pumping it is pushing water back into the boiler.

ziobeege_72 wrote:If the water in your boiler is getting 'dirty' from coffee then generally that means the seals are not sealing properly. Espresso is escaping past the first seal on the downstroke (likely to be the problem seal your case), past the second seal (which is expected as it is 'facing' the other way - with its job sealing water above the piston, not from below) and the force of the downstroke pressure is bigger than the pressure coming from the boiler resulting in coffee finding its way into the boiler. No wonder you are finding it springy with little resistance.

I had a similar problem with my PV Lusso with a dirty boiler. It was that first seal that was the problem.

The trouble is that seals may seem fine to you to the naked eye, seated well and nicely lubed but often you cant easily what the problem is. You can get leak between the inside of the seal and the piston groove, or a tiny nick somewhere, or that the seal itself isn't perfectly snug. OE has a solution that helps fill the gap of the piston groove so that it fills the seal better. I think that is where you should be focusing on.

Here are photos of the inside of the group and the piston. I took the interior group photo with an iPhone backed up to the drip tray because this group isn't easily removed. I don't think anything's broken there. You can see the weep hole at the top and the hole that flows water into the group below it. I believe the issue is piston gaskets that are too soft and easily give way. And these are the factory gaskets.



I put spacers on the piston rod following Tomaso's (at Zacconi) suggestion that a spacer would help keep coffee from getting into the boiler. I removed one of these before installing. When the piston gaskets slip, coffee gets by them and into the boiler.



Here are the two portafilter gaskets I tried. The white one is the stock gasket from Zacconi. It's very soft, like a rubber eraser and the edges bend. Trying to get it into place and tighten down the portafilter it easily shreds. The black one is supplied by Orphan Espresso. Both seem to fill the space and the portafilter appears to lock in tight, but tonight the portafilter exploded out of the group, spraying coffee everywhere and ejecting the shower screen into the capp cup it broke underneath. This makes me wonder whether the portafilter tabs are not fitting tightly in the group, but as you can see the group appears undamaged. I checked the boiler pressure at that time and it was 1.3 bar, not extremely high. The measurements of the portafilter gaskets are slightly different with the OE one slightly smaller, but both fill the groove around the shower screen and neither holds the shower screen in. It snaps in place. Both portafilter gaskets seem to lock in the portafilter very tightly.



You would think this should be simple. The portafilter gasket holds the portafilter in place and keeps things pressurized. The piston gaskets allow water into the cylinder and push it down and if water gets above them it exits the weep hole. Why is this not working? And does anyone want a fancy milk steamer???

I have a similar problem with my Graef ES 90, losing pressure and/or dripping from the PF gasket.
This behavior has been identified, and well explained in Coffee Snobs, with the identical Sunbeam 6910.
In this case the problem is that the group collar wears out, they call it "lipping" and the PF (and filter) are not able to seal well anymore. As the PF is made of ss, it's harder than the collar that seems to be of a zinc or aluminum alloy, and wears out the collar when forcing the PF in place.
As the gasket and the collar are very smooth, it's quite difficult to perceive when you're over thightening and deforming the group collar.
In Australia they just replace the collar (about $80), as I can't get one here I added some paper gaskets (shims ?) that took care of it.
Latter, as I had to replace the original gasket, the shims wouldn't do the work anymore and I had to use another filter with a higher lip, that seals much better, with no leaks about 90% of the time.

That is very interesting. It seems like the next best fix attempt, then, is to shim under the portafilter gasket? This fits my experience that when I first installed the white portafilter gasket the portafilter didn't blow out of the group and the seals weren't slipping. The difficulty was that gasket was so soft it started badly shredding on the second install.

Yes, under the PF gasket.
I used (as recomended in the german Keffeenetz) magazine cover paper and a compass.
After marking the center I cut the paper with the needle side of the compass, just turning around and around.
With the shims the PF will seal earlier as the "ears" will make contact with an unused part of the collar lips.