Peppina Redux - Page 9

[espressme]

The greatest problem with these machines is that a normal machine vocabulary does not handle the upside down piston configuration.
Draw a sketch of the washer positions and where the piston is and what happens when you do what. I had to do that.

Washer under kettle - over piston. (Cylinder is a hypodermic syringe business end up., plunger thumb rest down.)

Channel below washer to the group washer and over it, and the Pf below.

Lever up, piston up. (Thumb plunger in {spring loose})

Lever down, piston down.( Thumb plunger out { spring compressed })

In between, what happens to the flow?

Syringe sucks from kettle through the opening piston washer - can't draw from the group because that washer is closed.- Closes that piston washer and squirts to the group through the opening group washer. washers assure flow is in the correct direction.
Have fun!
richard
Play with her for a while and decide for yourself about washers when the action is clear to you.

Okay, more overthinking here (sorry Rich):

What I'm gathering is that although my La Pep is probably capable of making me a decent shot with some practice, that she really does have not so good valve washers and that if/as/when I actually dig down farther and replace them that there will be NO water coming through the brew group when the lever is pulled down the first time.

Izzat right? She may be okay but not any better than that at this point?

And, by the way, Rich, the only thing better than working at home is NOT working at home (after having worked at home for years and years and years).

Susan

[SJM]

Draw a sketch
Have fun!

Two excellent ideas (as usual)
Thanks.
I'll keep quiet now for a while until I get some smarts where my questions have been.

Susan

[timo888]

Water trickling out to the puck from the force of gravity is not, in and of itself, a bad thing, since in most real-use scenarios, it would be followed in a second or two by more water under spring-pressure -- under full spring pressure if the barista has let go of the lever, or under partial spring pressure if the barista is restraining the lever.

On an old machine with old washers, you can safely conclude from the trickling that the small group washer is too stiff*. Too stiff, and some water trickles down; but on multi-pull shots, with the upstroke of the piston some coffee oils will be drawn back from the wet puck into the channel connecting the group to the piston chamber. This is not a show-stopper, but the washer should be replaced when you get a chance and the right tools to remove the group bell. However, upon removing the bell, you may discover that the o-rings have rigor mortis ....

Regards
Timo

*Yet on a machine using the thin nylon-reinforced washers I used to have a stock of, the trickling was actually an indication that the washers were very pliable -- they would not let coffee oils back into the group because they would get drawn tight against the group head with the piston upstroke.

[SJM]

One more (tiny) question: I have the exploded diagram of all the parts, with numbers attached, but....is there a list that I have missed that names those parts?

Oh, nevermind. I see that there are now coffee grinds in the kettle.
Bad juju. Flapper valve has to go.
Where do I find one?
Nevermind, I found that thread with the reference to the parts supplier.

Further deconstruction to follow....No sense not doing it right....

Dang...

[SJM]

Well, clearly I've gotten as far as I'm going to get for tonight. I've got the set screw out of the front and the bolt holding the "clamshell" out of the back, and now I'm slightly stuck.

Timo, I've been reading your notes from April 3 of last year, and at this point it seems that you were trying to rotate the "chassis". I haven't been able to discern whether rotating it was how you were trying to get it apart, or whether rotating is how it has to be gotten out.

Can you possibly clarify the next step(s)?

And, by the bye, as I understand the mechanics of this machine: as long as I leave the lever in its up position, I am not in any danger of opening something that is going to let it go off on me....right?

I'm going to shut down for tonight....back to it tomorrow.

Susan

[Bushrod]

I had an aha moment last night. Apparently, what I though was a "light" tamp was not very light at all.

I made two wonderful shots just using the weight of the stock tamper to tamp. Just the barest kiss of compression.

What a difference! Now I know what you mean about making it sing.

[timo888]

... I've got the set screw out of the front and the bolt holding the "clamshell" out of the back, and now I'm slightly stuck.

Timo, I've been reading your notes from April 3 of last year, and at this point it seems that you were trying to rotate the "chassis". I haven't been able to discern whether rotating it was how you were trying to get it apart, or whether rotating is how it has to be gotten out.

Can you possibly clarify the next step(s)?

.... as I understand the mechanics of this machine: as long as I leave the lever in its up position, I am not in any danger of opening something that is going to let it go off on me....right?

Look for the picture of a small stubby screwdriver sticking in the back of the housing, as though Colonel Mustard had murdered Peppina in the Parlor with it. You tap the screwdriver gently into the housing to spread the clamshell apart a little.

You can rotate the group back and forth (i.e. it isn't threaded), wiggling it upward as you do so. This takes no little amount of effort, if you find yourself wondering, "Should I really be pulling this hard?" Also, it seemed to me that the housing was easier to remove with the lever depressed, and IIRC Richard used a clamp to do this. I used my thigh and knee to hold the lever down, and came very close to regretting that decision big time.

The lever arm is bolted to a sort of cam near the base of the machine; the spring won't jump out at you if all you do is remove the group housing as above. The piston will be exposed and on it you will see a rather hefty o-ring that seals the piston cylinder. That too ought to be replaced if you have the old machine opened up. Spread a little dab of Dow 111 (available over the internet if your local supply house is dragging their feet) on the new o-ring before you place it on the piston, and afterwards as well. A little dab'll do ya.

Regards
Timo

[timo888]

I had an aha moment last night. Apparently, what I though was a "light" tamp was not very light at all.

I made two wonderful shots just using the weight of the stock tamper to tamp. Just the barest kiss of compression.

What a difference! Now I know what you mean about making it sing.

These domestic spring levers produce approximately 6-7 bars of brew pressure, and an older spring might produce somewhat less than that, so you want to make the puck penetrable. 'Cake' is probably a better word than 'puck', because 'puck' implies a hard disk with well-defined edges. With a light tamp, the natural hydrostatic swelling of the cake of ground coffee during the preinfusion phase will yield a delicious espresso.

Regards
Timo

[SJM]

Look for the picture of a small stubby screwdriver sticking in the back of the housing, as though Colonel Mustard had murdered Peppina in the Parlor with it.

Actually, I'm one step behind the scene-of-the-crime picture. I still don't have the shiny upper part removed from the grey lower part, but I think this is where I have to lower the lever to get one of the parts to let go of the other? Richard, can you tell me how the bleep you got a clamp to hold that lever down?



I'm feeling defeated.

The UPS man just brought my right angle ratcheting screwdriver, and....even with that I can't get those screws undone. It seems like the shank is just a hair too short so that I can't get the driver fitted into the screw slots, and it also seems as if the driver is just a hair too wide for those slots (but I can't tell because the angle isn't good.

Oh good, there's the phone....You won't have to listen to me whine.

Susan

And after that I was about to just put her back together again when I managed (by doing exactly as I was told with the screwdriver between the parts in the back, and lo and behold the chromed part has come about 1/4 inch out of the base. Guess there's no turning back now....

And I don't know if that's good or bad....but it is what it is....

Susan (again)

[SJM]

H U R R A H ! ! ! ! !

Top is off the bottom !

I wonder if they teach their techs to do it this way. Put La Peppina on the floor facing you. Put your left foot on the left side of the drip tray. Use your right foot to bring the lever down to the floor. Stand there holding the lever down while you do the next step: NPut a heavy duty rag along the side of the plug holder and whack it repeatedly until it shoves around a millimeter or so....

I hope not, because all that will do is convince you that it WILL move, and then deform the plug holder so that the safety gizmo pops out and will NOT go back in. Oh well, who cares about that anyway....

However there's the next step still to come: put the chrome part into the vise (protected well all around by soft rags) and whack the you-know-what out of the drip tray with a rubber mallet (no hammer this time) until you finally get it worked all the way out......Right....Whew....


Guess I won't have to throw her (or myself) in the dumpster after all.

If I can do it ANYONE can !
Youse guys aren't off the hook yet, by a long shot.
This is just the beginning....

Susan

[timo888]

Colonel Mustard's murder weapon spreads the clamshell slightly, to make it a little easier for the acrobat who would remove the group from the housing. You twist the group, as you did, so the plug is no longer on-center, then tap the driver gently into the shell to open it up a bit, and then pull the group slowly out by turning it back-and-forth, pulling up on it all the while.

Regards
Timo

P.S. Now that you have removed the group from the chassis, you can remove the difficult screws from the dispersion screen.

[SJM]

Now that you have removed the group from the chassis, you can remove the difficult screws from the dispersion screen.

Everything in the ripeness of time....(as long as Susan doesn't break it first....)

Susan

[mogogear]

You Ma'am are a champ! Three cheers for reading , application, and intuition! Also, "Want to"

[espressme]

You Ma'am are a champ! Three cheers for reading , application, and intuition! Also, "Want to"

Awomen!
rp

[SJM]

Thanks for all the encouragement.
I just spoke to Sergio, and he is going to be putting together a gasket/washer package for me.

Meanwhile, I will start getting her ready for her new software...

Susan

[SJM]

The screw (part #1154) holding the rubber washer (part #1130) is frozen. I'd be grateful for suggestions on how to loosen it.

Okay, I'm going back to see if anyone chimed in on this point and then will edit this out if so, but meanwhile it seems to me that the screws are the hardest part of this whole machine.

They seem to be made of such soft metal that they squish before they let go.

Is there something that will help to loosen their grip? Will citric acid soaking loosen the extra stuff that has grown the parts together.

And, by the way, that flapper part on mine looks pretty good, although I am going to replace it. It's still intact and still quite flexible.

Okay, a few pages on and I see that Timo still hasn't gotten the screw loose (I mean the one in La Peppina, by the way)

I'll try to seat a new flex washer over the frozen screw and will abandon my quest to free the frozen screw if that succeeds. If it fails, I will look for some food-grade penetrating oil and try to loosen the screw that way before turning to a dremel or the torch.

Back to reading, but if anyone can get me to the end of this particular chapter faster, it would definitely be helpful.

Susan

[timo888]

Back to reading, but if anyone can get me to the end of this particular chapter faster, it would definitely be helpful.

I tried heat (soldering iron applied to the screw) and days of soaking in edible mineral oil, but the screw simply wouldn't budge. The dissimilar metals seemed to have melded together. I finally settled on washers flexible enough to fit over the head of the screw.

Regards
Timo

[SJM]

but the screw simply wouldn't budge. The dissimilar metals seemed to have melded together. I finally settled on washers flexible enough to fit over the head of the screw.

Regards
Timo

Ah, well that makes me feel a bit less wimpy then.

I just had Sergio send me a full set of gaskets ($100?!)

Do you have any idea if the one he is going to send will be flexible enough to do what you did?

[espressme]

Aha So that is why mine went to the little local machine shop to get it out! Not bad, 30 bucks and it was removed and re-threaded. That allowed me to resurface the washer seat. The remains of the little screws of the group do sometimes take a Dremel! They are dead soft and may break off.
Susan, ask for a set of the group screws also. They are worth having.
Cheers
Richard

I tried heat (soldering iron applied to the screw) and days of soaking in edible mineral oil, but the screw simply wouldn't budge. The dissimilar metals seemed to have melded together. I finally settled on washers flexible enough to fit over the head of the screw.
Regards
Timo

[SJM]

ask for a set of the group screws also. They are worth having.

I'm quite sure Sergio said he was including these.
Whew !

Susan