Building the Ultimate La Pavoni Europiccola - Page 11

Equipment doesn't work? Troubleshooting? If you're handy, members can help.
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drgary
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#101: Post by drgary »

Sure, but it be awhile before I get to that. I can say that the current model is functionally capable.
Gary
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drgary
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#102: Post by drgary »

An update: I've been using this "ultimate" machine for coffee this Christmas morning for me and my wife. Although there are some items yet to be completed and redone, it's going to be one of my best manual lever machines.

Currently I have a Jaeger PSTAT installed after having trouble getting the La Pavoni PSTAT to properly seal to the pressure fitting. The La Pavoni PSTAT female connection is concave and plastic. The Jaeger is metal and a flat surface and seals perfectly. I still need to bend the PSTAT pipe so the edge of the Jaeger fits fully under the bottom without slightly bulging against the rubber base. Other items left to do are repainting the base -- even at the low setting the base near the boiler heats to 220°F and beyond. The paint is specced for 200°F maximum, so it softened and wrinkled. Since I'm using the stronger, modern 1000W heating element controlled by a PSTAT this machine runs at a higher temperature than it did with vintage low and high heating element setup while also constantly venting steam. So be aware that the back of the base gets boiling hot and will need to be avoided along with the boiler. (Mods like this are done at your own risk.) This will also call for a different paint than the original may have been. It also gives a clue about the Olympia Express re-design into the Cremina version 2 to accommodate a PSTAT, where the boiler is enclosed and the outer parts of the steel frame are less vulnerable to transmitting heat. I also wonder whether La Pavoni Europiccolas and Professionals with the cast steel base don't sink heat as efficiently as the original aluminum bases.

The old lever pins protrude far beyond the lever fork and allow play. Over time that play wears away chrome at the top of the group. I'll make brass lever pins terminated by acorn nuts and possibly spaced by washers. I still will experiment with a roller bearing in the back. As it is the functioning of the machine is very smooth but these mods should make the action smoother, eliminate lever play and reduce wear except on the brass pins, which will be consumable parts. I'm also thinking of how to measure group temp. But I'll have to say that I've got enough practice with these machines I was able to temperature surf quite well without measurement. That may be due in part to the group on version 1 machines being such an excellent heat sink.
Gary
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gunman45
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#103: Post by gunman45 »

drgary wrote: The paint is specced for 200°F maximum, so it softened and wrinkled. Since I'm using the stronger, modern 1000W heating element controlled by a PSTAT this machine runs at a higher temperature than it did with vintage low and high heating element setup
Hi Gary and a belated Merry Christmas,

I read somewhere that standard powder coating can withstand 300 deg, hi-temp can go to 1,000. Is that an option for you?
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Larry - LMWDP #536

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drgary
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#104: Post by drgary »

Merry Christmas to you, Larry. powdercoating could work, and I've done that with other machines. I'd like to figure out a more straightforward DIY method, since this is a teaching thread. Fortunately a friend pointed me to a local specialty paint shop in Vancouver, WA, Bob's Paint Land. They advise on hobbyist projects, so let's see what I find.
Gary
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forbeskm
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#105: Post by forbeskm replying to drgary »

Understand the teaching thread. I'll add that one can find a powder coater or media blasting place nearby it can be cheaper than one's time and effort in paint and materials to powder coat. I had a base plate of my Cremina media blasted for 20 bucks which saved me time, they did it while I waited and I spray painted it when I got home. I also had a base stripped and powder coated for 35 (a few years back, probaby ~40-50 now).

Just adding as no you likely cannot do this at home from a 100% teaching side of things, not everyone has a media blasting box or powder coating but many small shops can help you out for a reasonable price to get you beyond your skills.

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drgary
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#106: Post by drgary »

Good suggestion, and I agree. I'd like to find a hammertone in a nice color. This place may media blast on premises.
Gary
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forbeskm
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#107: Post by forbeskm »

My powder coater had to redo one of my aluminum bases as we didn't keep the base dry enough and even powder coated sitting in water is evil. Second time round and he did it for free he made sure to do an epoxy coat underneath the powder coat as the aluminum bases corrode as well. The metal bases get zinc coating before he powder coats them. Just makes sure to check on prep as its its important for powder as it is for paint.

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drgary
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#108: Post by drgary »

Paint is Not the Problem?

During the last few days, I researched paint that is more forgiving of higher temperatures. Then one day I noticed the pressure soaring to 1.5 bar without the PSTAT shutting down. I assumed there was a leak at the PSTAT fitting. I unplugged the machine, put it away and inspected it last night. There was no leak at the PSTAT. Instead I was using the base as a heating element. Here's what I mean. The switch had a bare contact that I assumed wouldn't touch the base because of its OEM design. Wrong. I discovered that contact was touching the base and arc welding it.



No wonder the base was getting hot! I covered those contacts with many wraps of Rescue Tape.



The base no longer overheats, reaching a maximum of 167°F. The PSAT has resumed its regulating function. At this temperature the paint is well within its tolerance and won't soften. Most importantly I've found and fixed a dangerous short.
Gary
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#109: Post by drgary »

Paint is Not Ideal, So...

Further measurement has shown the boiler bottom lip where it meets the base reaching 220°F even though close to that the base measures less than that, but it's pushing the 200°F limit. Close inspection shows the paint somewhat degraded where the boiler attaches. Also the paint feels tacky when the machine is fully heated. It doesn't soften enough to lose shape, but it's a bit grippy. So I'm going to opt to use engine paint when I get a chance. I researched paints with a shop selling to professional auto painters and found their solutions very pricey. The least cost one was a catalyzed paint where you buy the can for over $20, then they fill it with the paint of your choice for over $40 if I remember correctly. One would get an endless selection of color. Then there's also a catalyzed primer. (Catalyzed means it's a similar process to mixing the ingredients in epoxy.) In any case, this was far more expensive than rattle can paint in a hardware store, albeit much higher quality.

Yesterday I went to the most well stocked auto supply store in town and found the same type of paint Doug Garrott used on my Lady Duchessa. He switched to that paint to avoid darkening of lesser paint when exposed to heat so that the boiler was looking darker than the base that holds the electricals.

The primer and paint each cost $6.99 before tax. And it's formulated to withstand transients temperatures to 500°F. That's more like it. Although the photo doesn't show it, the green color of this paint matches some of the green coloration in our granite countertop. I like it and it meets WAF.

Gary
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#110: Post by drgary »

Why La Pavoni Switched to Steel Bases

Experimentation like that in this thread can partly retrace the quest of espresso machine manufacturers to advance their machine features. Adding a 1000W heating element with a PSTAT improves steaming and ease of use over the old system of 200W and 600W dual elements that are manually switched and constant venting of steam to dissipate heat. But the base now gets hot enough it's uncomfortable to touch. Most of the base won't cause burns, but still, aluminum is too good a conductor.

I believe that this is why La Pavoni switched to steel bases when it introduced its second generation of machines, including the Professional that for the first time incorporated a PSTAT and a manometer. This introduced a rust hazard, but I expect those bases run cooler, since steel is a less efficient conductor of heat.

This also may help explain why Olympia Express redesigned the Cremina to its current 2nd generation configuration of a boiler mounted to a steel base and enclosed by a case.
Gary
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What I WOULD do for a good cup of coffee!