# Microcimbali - pimp my snow globe



## jimbojohn55 (Jan 15, 2016)

I couldn't resist a lever with little bolts on the front - these are very much off the radar although in production from 1954, this is a 98 model with a pressurestat the earlier models having twin elements - kindly supplied by @coffeechap in a driveby hopper swop in a m62 service station car park.

Unfortunately its in great nick so no major rebuild - booo, maybe the piston seals - more pics to follow later - and the snowglobe effect !









a wee bit bigger than a pav!


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## jimbojohn55 (Jan 15, 2016)




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## Jacko112 (Oct 29, 2015)

Don't these suffer from the aluminium boiler Jim?


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## ashcroc (Oct 28, 2016)

Looks good. How does the coffee out of it taste?


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## jimbojohn55 (Jan 15, 2016)

Jacko112 said:


> Don't these suffer from the aluminium boiler Jim?


they do - particularly the early ones - I'm optimistic that over 50yr production run they did something to improve the situation but im not sure - I found one thread in the USA forums that describes adding a small piece of zinc as a sacrificial anode, not sure it would work - the reason they have a tap at the bottom of the boiler on the steam arm side is so you can empty the boiler after use if you want to - bit of a pitta - and I will be tempted not to.

funnily enough there is a rumour they are still in production not that ive seen them for sale new ? anyone know

certainly you can get most of the parts inc a new boiler casting &#8230;&#8230;&#8230;...for £315 hahahahahahahahaha

https://www.bullonerosso.de/espressomaschinen/espressomaschinen/cimbali/microcimbali-liberty.html?___store=gb&___from_store=de


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## Jacko112 (Oct 29, 2015)

Yeah I considered one of these before the la pav but was put off by the boiler issue, I was quite tempted though by the spring lever. The other one I looked at was the la peppina. Both very decorative machines


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## jimbojohn55 (Jan 15, 2016)

at the moment its in descale mode - not tried it yet


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## jimbojohn55 (Jan 15, 2016)

So looking through the sight glass on the front after first fill shows an interesting snow globe effect - lots of tiny white snowflakes of white aluminium oxide - as it heats up it snows harder and little snow drifts start to form as the front of the glass - its worth getting one just to see this









Im now on my second descale using tartric acid as its a bit kinder on aluminium apparently - we will see - the machine came with a complete seal kit and I think after the descale it will be time for some new piston seals or at least a partial disassembly.


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## jimbojohn55 (Jan 15, 2016)

so looking into the use of anodes in aluminium water heaters and boilers - there is an interesting thread here https://www.home-barista.com/levers/putting-zinc-in-aluminum-boilers-t23830-10.html that explains things in a technical detail but basically if your going to do it you need a magnesium alloy anode designed for a water heater - fortunately such things exist and are fitted in aluminium water heaters in domestic and commercial settings - https://www.ebay.co.uk/sch/i.html?_from=R40&_trksid=p2386202.m570.l1313.TR0.TRC0.H0.Xmagnesium%20anode%20for%20water%20heaters.TRS0&_nkw=magnesium%20anode%20for%20water%20heaters&_sacat=0#item3aeaaaa3ee

The other fact is that if dried out occasionally the boiler forms a coating of aluminium oxide which helps prevent corrosion - it has to be completely dried out though - the white snow im removing at the moment from this boiler is "



hydrous aluminium hydroxide"
​
which needs to be dried out to form aluminium oxide - so why am I removing most of it - well there is a lot of "snow", so im getting down to a manageable level - that a lot of chemistry for a sunday am, but using an magnesium anode and drying the boiler out completely now and again seems the way to go.


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## jj-x-ray (Dec 31, 2017)

I'm a sucker for steam punk and I think that looks better than the la pav.

I'm guessing there are no substitute boilers in different materials. Good luck with the cleaning and sacrificial anode install...


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## jimbojohn55 (Jan 15, 2016)

jj-x-ray said:


> I'm a sucker for steam punk and I think that looks better than the la pav.
> 
> I'm guessing there are no substitute boilers in different materials. Good luck with the cleaning and sacrificial anode install...


Hi -the boilers are cast in an aluminium alloy, and not available in anything else - one option that I have heard of is getting them anodised to prevent oxidisation but ive not seen any done, will start with the anode approach and occasional drain and dry see how it goes.


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## jimbojohn55 (Jan 15, 2016)

Ok given the chance to open it up with seals to hand the clock was ticking-

piston end casting off -

Piston out -

shower screen off

porterfilter holder off -

cleaning its teeth -

cafiza (couldn't resist)


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## jimbojohn55 (Jan 15, 2016)




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## jimbojohn55 (Jan 15, 2016)

The inside of the piston cylinder was a bit rough so popped in a flap wheel to take the ridges out of the surface

compressed the spring with a couple of clamps - removed the handle and piston top nuts to separate the piston

removed the piston seals to find more snow behind them! the piston has these interesting rubber dot bumpers to prevent contact between the piston and the cylinder wall - not seen this before - and then a quick buff - what else


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## jimbojohn55 (Jan 15, 2016)

Removing the piston cylinder - curious this but I thought this would be really a pain with oxidised threads and nothing to grip, but all it it takes is a couple of light taps with a wooden stick from above and they just drop out - no threads at all, I was keen to remove it to look closer at any scoring on the cylinder walls and smooth them out


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## jimbojohn55 (Jan 15, 2016)

The piston cylinder after clean up showed that some of the nickel plating was missing and patchy at best - Ive been wanting to have a go at this and so after a lot of reading and youtube videos I had a general idea about the process - next stop ebay for Nickel anodes £10 for 5 99.2% pure - Nickle sulphate solution 1Ltr £12 - you can make this yourself but for a tenner its made up ready and has "brightners" in it to give a better finish

To start clean the object by mixing distilled viniger and salt for 30 mins or so to pickle it and get all the grease and dirt off it - then rinse - but don't touch the piece again with your fingers - use gloves from now on.

Basic principal - suspend object to be plated on a wire attached to the negative wire from a small voltage adapter - ive used a 5V one from an old phone charger

Suspend 1 or 2 nickel anodes attached to the positive wire

NB neither anodes should contact the piece (nothing happens but the process stops working)

cover anodes and piece with the nickle sulphate solution - Ive warmed it by putting it in a bowl of hot water

2 hrs later after moving the piece around and turning it over and bingo


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## jimbojohn55 (Jan 15, 2016)

shiny


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## joey24dirt (Jan 28, 2017)

Oh wow that's so good!! Science eh? Crazy stuff


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## ashcroc (Oct 28, 2016)

jimbojohn55 said:


> View attachment 34404
> View attachment 34405
> View attachment 34406
> View attachment 34407
> shiny


Always prefered a nickel finish to chrome. Thought you were gonna plate the boiler when I saw the pics yesterday.


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## jimbojohn55 (Jan 15, 2016)

ashcroc said:


> Always prefered a nickel finish to chrome. Thought you were gonna plate the boiler when I saw the pics yesterday.


Its a tricky process apparently - depends on the alloy contents as to what and how to do it - a pro shop could do it but I'm reassured at the thickness of the boiler about 4-5 mm so adding a magnesium anode should help, hopefully.

The thing about chrome is that its actually a final coating for nickel and so thin that's its transparent - so when you look at chrome its actually nickel you can see - aparently


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## jimbojohn55 (Jan 15, 2016)

I was just thinking a couple of seals and this will be back together when I spotted some snow around the bottom of the boiler - this cheered me up as I had a reason to now do a full teardown









Turn it over- remove brass retainer nut- to reveal gubbins (not sure why it has a small capacitor)? remove brass nut , set screws etc disconnect the three wires that poke through to the switch and element

undo the big brass nut ontop of the boiler - can you tell which one


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## jimbojohn55 (Jan 15, 2016)

Tap on the threaded bar with a small hammer to separate the boiler from the base and element


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## jimbojohn55 (Jan 15, 2016)

Remove the cover of the sight glass - it has a hard soild gasket, designed to put pressure evenly around the glass pressing the glass onto a soft rubber gasket

remove the filler tube from the boiler top (no gasket just PTFE)

Remove the pressure valve ( has a flat rubber gasket )


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## jimbojohn55 (Jan 15, 2016)

unscrew steam arm - the threads were caked with snow sound, so ran a tap through the hole to clean them out


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## jimbojohn55 (Jan 15, 2016)

Repainting the boiler flange - the cimbali has an interesting textured finish in a satin black - I decided to just sand down the bottom of the flange back to metal and then mask it off , etch prime and give it 4 coats of satin - I also needed to level off the bottom mating face of the boiler so that it would press evenly on the new o ring gasket - should look ok


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## jimbojohn55 (Jan 15, 2016)

the shower screen for these is odd - held on with two little nuts and four copper studs - after much looking at diagrams I realised that the studs hold in place a small flat rubber washer that works as a one way valve, stopping a second pull of the lever sucking up coffee and grounds up into the boiler - Of course there was one in the seal fit from Francesco.

The seal is so good that when I trial fitted the piston holding it by hand I couldn't remove it without removing the shower screen - needs a lever on it me thinks


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## jimbojohn55 (Jan 15, 2016)

Then of course the obligatory buff of the bakerlite parts, just for the shiggles - it has to be done


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## Stanic (Dec 12, 2015)

jimbojohn55 said:


> Unfortunately its in great nick so no major rebuild - booo, maybe the piston seals - more pics to follow later -










 well, you kept to the last statement









incredible work, can't wait to see it put together


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## jimbojohn55 (Jan 15, 2016)

You know the title sequence for the Simpsons with the rod - well couldn't help but think of it when the postman turned up with this - there is something a bit odd about rods of strange metal (Magnesium alloy) that turn up and say made in Chin - no e !

Anyway clearly it is sacrificial anode designed for aluminium water heaters so in theory is should be fine - probably - I mean the thing is supposed to corrode rather than the boiler case and magnesium is an essential part or your diet - tap waters full of it









I cut it down to a manageable size - rather than have it loose in the boiler ive strapped it to the central mast like Turner in a storm - except with stainless steal straps


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## jimbojohn55 (Jan 15, 2016)

reassembly - just a reversal of the teardown with new seals and gaskets


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## MildredM (Feb 13, 2017)

^^^^^ shine-eeeeee!


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## jimbojohn55 (Jan 15, 2016)

And back on with the boiler, new o rings all round - tighten the nut onto the central column with a new copper washer, add the pressure relief valve, filler tube, grease up the piston - compress and hold the spring to get the lever on and in it goes. sight glass on the front, steam arm back on and shes done


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## Jacko112 (Oct 29, 2015)

Looks great Jim. Be interested to hear about the quality of the coffee it produces


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## jimbojohn55 (Jan 15, 2016)

and after a quick warm up she settles at 0.3 bar as it is supposed to (why am I saying she) if you gave I a name its more of a Manfred or a Burt ...

anyway no leaks - load her up with 14G and away she goes smooth spring lever action - unfortunately I wont drink it till ive boiled and drained it a few more times - but she / he looks good


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## cloughy (Apr 11, 2018)

Impressive! nice work


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## Stanic (Dec 12, 2015)

a beaut!


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## jj-x-ray (Dec 31, 2017)

just stunning.....awesome machine and awesome job, well done

This is the coffee machine Isambard Kingdom Brunel would have used


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## jimbojohn55 (Jan 15, 2016)

jj-x-ray said:


> just stunning.....awesome machine and awesome job, well done
> 
> This is the coffee machine Isambard Kingdom Brunel would have used


Ha - interesting design note - the early machines had the bolts on the sight glass then they switched to countersunk screws, but due to demand brought them back again!

Its a hefty bit of kit dwarfs the pav - will post up some side by side later along with a video or as Isambard (which is a good name for it) would say a "launching"


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## jimbojohn55 (Jan 15, 2016)

Just a quick update a week or so into use - there is limited info about how to pull shots on these, the instructions from Cimbali that ive seen translation of suggest that the lever is pulled twice, certainly this gives you a 40ml - 50ml shot from 14g but not the best taste so far - the secolever rise is very quick

so this is where im at after dialling in ect

Half fill machine - heat up till the pressurestat kicks in at 0.3 bar

Turn on steam to drop the pressure again for second heat up

A quick blast on the lever to clean the screen and heat the portafilter

Dry the portafilter add coffee and tamp ( the coffee is a finer grind that the 49mm Pavs)

Portafilter in place, Lever down and hold for pre infusion

lift lever slowly (usually till its at 180 deg) at the point its just starting to put some pressure on the puck

lower lever again for a second or two

Lift lever till it holds the pressure and leave to rise on its on

Result 30ml (but let it drip for 30 sec after the main shot finishes)

Taste - great - but early days still

Steaming - lots and lots of steam but the nozzle sucks big time and needs changing


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