1958 La Cimbali Gran Luce Automatica (Hydraulic) [Finished] - Page 9

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IamOiman (original poster)
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#81: Post by IamOiman (original poster) »

boiler lids and group flanges are retrieved

I finally got my requested repairs completed, and collected the two boiler lids and group flanges today. I had to remove a total of 9 studs that were damaged or fully torn off, but I think they should all be set. I'm quite excited to try out the viton boiler gaskets I ordered, and they fit perfectly. I tried keeping the plating on the lids as best I could. The flanges were cleaned in the tumbler.






One of the boiler lids (heating element side) still had the old boiler gasket, so I scraped it off. It was much easier to remove than the one on my Cimbali Eleva as I was able to get under the gasket and peel off big chunks at a time, with minimal residue remaining that was scraped off then wire wheeled. The boiler threads that the manometer 1/4 BSP fitting screws into is damaged so I will need to procure a tap to clean the damaged threads. I had purchased 1.5 inch long 5/16 studs, but that is too long for one of the studs that secures the wobbler weight fitting (it will touch the fitting if too long) so I needed to cut my own to 1.25 inches.



-Ryan
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IamOiman (original poster)
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#82: Post by IamOiman (original poster) »

Now that I have the group flanges, I could mount the first group. The group studs I originally procured were 3/8 x 2 inches long, but I had to cut a few custom 2 1/4" long studs when I realized the group nuts would not have many threads to grab with the shorter ones. The group nuts can thread up to 3/4" deep, and I aimed to have at least 1/2" of thread going into the nuts. Each nut has a ptfe gasket for further sealing. When installing the group, the front gas shield must be placed right before the group or it will not be able to go on after. I did use a little Loxeal 18 for supporting the group gaskets on both sides in sealing, as I do not want to redo this step if possible










With the group on the boiler, I applied lots of grease on the big piston and installed the big cap. It squishes an o-ring to make a seal against the upper group with six 1/4 x 1 inch bolts. I installed all of the pipes too, and I intend to test the hydraulic circuit soon. It is a really cool group just in terms of looks.




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IamOiman (original poster)
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#83: Post by IamOiman (original poster) »

I got the other group on this morning after cutting more studs to around 2 1/4 (just under that).







I am test fitting the boiler lids too. I confirmed the heating element will fit in the boiler (ie it's not too long). The manometer for the hydraulic circuit has a support bracket that acts as a washer on one of the boiler bolts. I am using a manometer from newer Cimbali machines like the M21 Junior. The safety valve fitting also fits with its shortened stud too but you can see that the shorter length is necessary. I used a longer stud for the heating element to attach a ground wire.



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IamOiman (original poster)
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#84: Post by IamOiman (original poster) »

The frequency of posting and number of pics usually indicates my excitement. Today is pretty up there in how giddy I am.

I kept going with assembly. I installed the lower chrome panel that goes around the bottom frame along with the gas shields. I made a bracket for my Sirai/Asco pstat and wanted to check if it would fit where I wanted to place it. I installed the rear body panels, which is supported by #10 screws that go onto two brackets on the bottom frame.





It's a good thing I checked as there is definitely interference with the pstat and body panels, so I will need to figure out a new spot or re-do the pstat bracket. Of course I did not waste the opportunity, and took some photos of the panels actually fitting after taking off the pstat 8) . Even if I don't use it, the Gran Luce is quite the looker.



-Ryan
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#85: Post by IamOiman (original poster) »

First testing of hydraulic circuit

I managed to scrounge up some adapter fittings to hook up my hydraulic circuit to my MacGyver'ed pressure regulator assembly. I first did a pressure seal test of the regulator, then I connected to the Gran Luce via a 3/8 BSP braided hose. I only had the manometer connected, and it serves as a secondary indicator of what my line pressure is at. Right now I fiddled with the pressure to be set to just under 1.8 bar. It looks like I lose a little line pressure going into the machine, but I can just play with the settings of the regulator to get around that.




Once satisfied, I hooked up the assembled group inlet/outlet pipes along with a temporary drain hose into a bin. I turned on the water line and I heard gurgling as air was escaping the circuit (when I had a valve open for purging it). I had very minimal leaks on the pipe fittings, and it was at this point I had to try 'pulling a shot.'





It's simply incredible tech. The vid is shown with a double espresso selected.
And yes, I did measure both the single and double shot water usage.

-Ryan
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IamOiman (original poster)
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#86: Post by IamOiman (original poster) »

This is where I am stopping until a shipment arrives to wrap up assembly of the boiler lids. I got the cap on the 2nd group and was able to test it successfully, but I had a failing compression nipple on one of the pipes that now leaks a little less after fixing. It will need to be addressed long term but the leak is small enough that I can accept the tiny dribble during testing.






Overall I would consider today to be quite successful and interesting. I am getting pretty hyped up for the first shot!
-Ryan
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Jed
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#87: Post by Jed »

That video is mesmerizing! Incredible work!! It's so cool seeing this thing coming to life and it is drop dead gorgeous to boot.

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pizzaman383
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#88: Post by pizzaman383 »

The operation of the group is amazing! I hadn't realized that the piston operation is controlled by feed water not boiler water. Very cool.
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IamOiman (original poster)
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#89: Post by IamOiman (original poster) »

Definitely a unique design. I knew hydraulics were a thing but working them really opens up how wild the concept is.

Last last update: sight glass and water inlet pipe

I just kept on chugging this evening. I made a water inlet pipe to replace the one that had two tears. I installed the boiler lid to help figure out how to bend it properly. It has 8mm OD pipe with 3/8 BSP fittings. I also installed the water sight glass. Note that with the modern 12mm OD glass, the brass bushing that help compress the sight glass gasket will not fit (but the chrome nuts work fine). I had a vacuum valve with a little cylinder to catch water escaping but that was too tall and touches the top of the body chassis.





-Ryan
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austinado16
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#90: Post by austinado16 »

Just sitting here with a huge smile! Fantastic!! Thank you for the photos and the video!