1953 Gaggia Classica 1 Group [Finished] - Page 3

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

It's been a few months since I posted about the Classica becuase I was tracking down two parts for it (a sight cover for the water level glass and the plexi). I also had to place a thread insert on a bad group thread.


Luckily the parts were sourced and finalized this week so I started assembling the machine in a temporary setup to check the integrity of the boiler and a weird little 5/16" 18 TPI screw that threads into the center of the bottom boiler 'arms'. I think it was added after leaving the factory but I need it to be sealed properly because I cannot access it when the machine is assembled due to the backsplash covering it. Used a fat wad of teflon tape to get that dealt with. I checked one more time that the boiler threads were in good shape and I used 30mm long stainless steel bolts that thread in nicely. The boiler lid itself has a workaround for the two extra holes on top since I only have one element installed. I added the vacuum valve to one hole which will be isolated from the heating element when fully assembled. The unused hole in the lid is just plugged and can be used for manual filling. Everything is 3/8" BSPP.







In this state + later adding the lower drip tray I brought the machine upstairs, and even without everything installed it was an effort due to the weight, which is over 68 pounds/31 kilos with the drip tray. I had to reweigh a few times to confirm the huge mass but it makes sense why I struggled moving it! They don't make 'em like they used to :lol: I had my little bowls to catch any water and allow me to diagnose anything suspicious. Once upstairs I just hooked up a power cable directly to the terminals and enable power at my GFCI reset button.






The element itself is rated for 1500W 110V, and when I turned it on for the first time I was struck by two things: it heats up quickly (just over 10 minutes with 3 liters of water) and it is very quiet. Hardly any water came out of the vacuum valve and it sputtered for a second before sealing. It's a little weird to not see a manometer but I turn off the machine when the safety valve starts sputtering. I don't know what the wobbler weight is rated to start releasing steam but it is quite heavy at nearly 1.5kg. I was able to flush the group (without the shower screen to allow debris still inside to escape) to satisfaction and tightened all the bolts and gasket stack when the machine cooled down overnight. I turned it on again this morning to similar results and so far nothing is leaking from the boiler outside of the temporary fittings I installed.




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

After changing the water out in the boiler I was almost ready for the first shot. However I needed to borrow a cafelat portafilter gasket from my Marte because it is the only one that will fit into the Gaggia Lever group without fighting me while also installing an IMS shower screen. The other gaskets are just too hard.



I waited 80 minutes for the group to heat up fully, and I pulled the first shot with the original portafilter. It tasted ok but the machine needed to heat up more and I needed to adjust the lever a bit. Unfortunately the video was not recorded properly but I at least have a pic of the moment.



I did take a 2nd video with better results, and after I adjusted the lever. In this configuration I need to do a Fellini pull but the result is something just great. I basically got a dark choco bar in the shot. You can also see how much space I have between the drip tray and the portafilter. I can easily fit my tallest cup with no issue. I am quite happy with the results but I cannot call this project complete until all the fittings and panels are installed.

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

I have tested the machine under pressure enough to decide the boiler and lower screw are sealed fine without issue, so I will take off the grouphead and front foot so I can install the backsplash then fittings. In prep for the full assembly I cut a pstat bracket from a 20 mm wide x 2 mm thick aluminum sheet, then bent to shape and drilled. I installed the big panel piece to make sure the pstat does not brush against it and fits in where I placed the bracket. I also placed the top on so I could confirm the boiler lid pieces have a gap/are not touching, and if I could secure the lid with its screw. However without a plexi it looks a little incomplete...










A quick two day trip from Hong Kong and the replica plexi + some other bits were received today. Paul did a great job with the plexi and sight cover glass. I quickly installed the plexi to confirm it fits. From the back the Classica looks complete, but going to the front you can see a few bits not installed yet.






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

Juggling multiple reassemblies right now, but I got the Classica valves all installed tonight.

The water inlet was first, where I pressure tested it with my FloJet to 2.7 bar which passed without issue on both the boiler side and inlet side. I also added a second gasket for the pin the lever presses against to open the valve, where only one was pictured. These valves are very beefy, the inlet for example weights 1.2kg :shock: .




The steam and hot water valves are identical besides the length of the tap rod (longer is hot water). The only sealing gasket is the one going on the tap rod. The teflon packing rope and teflon gasket only seal for the steam/exiting water.




The lower sight glass also has the hot water valve, and this is the biggest valve assembly. I partially assembled it off the frame then installed the hot water valve when I installed the former on the machine. The elbow fitting is for the pstat pipe that I will make. Any threads that don't have any gaskets seen were sealed with Loctite 55 thread (for all valves). The 1/2" BSP threads I wrapped 6-8 times, the 3/8" BSP threads 5 times, and the 1/4" BSP threads 4 times.



I forgot to take pics of the manometer/upper sight glass assembly but it was nothing surprising, and similarly went together as the other valves. I did have to take off the left two studs of the group while tightening the assembly.



With the valves on I worked on the sight glass. I purchased a new 12 OD x 2 thick x 500 mm borosilicate glass tube after I realized my old 1/2" tube was too wide for the E61 sight glass gaskets. I measured 215mm between the upper and lower fitting holding the glass, and a depth of 5mm on the lower fitting and 10mm for the upper fitting. What I needed to do was cut the glass tube to be long enough for the 215mm clearance and short enough to slip the glass tube in (ie less than 230mm). I settled on 223mm, and after marking and cutting the tube (and sanding the cut end gently) I was satisfied with the results. Paul Pratt supplied a replica cover piece (thanks for that 8) ), and with some fiddling I got everyone on without issue.









And this is where I stop for now. Next step will be making the pstat pipe and the proper wiring setup, then I can do a final test.
-Ryan
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IamOiman (original poster)
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#25: Post by IamOiman (original poster) »

Sifting through my pics I managed to find the manometer/upper sight glass assembly. The little flathead screw that goes on top of the elbow fitting for the manometer used a 02025 o-ring to make the seal. For the sight glass I used 2 E61 sight gaskets on each side.
-Ryan
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IamOiman (original poster)
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#26: Post by IamOiman (original poster) »

The pstat pipe was brazed up this morning then cleaned up with citric acid followed by a wire wheel. I had to make sure the pipe did not interfere/touch the big front foot and the gas regulator to snake its way to the connection elbow fitting on the lower sight glass assembly. The pipe goes inside then wraps around the boiler and eventually gets to the pstat.





The wiring setup was completed too. I installed heat shrink and the boots where the heating element terminals are located so the vacuum valve does not get those wet during heatup (although hardly any comes out from past testing and I have the GFCI breaker if contact does occur).




I cannot test it right now because I need to wait for some space to free up in the kitchen due to other machines occupying counter space and my helping hand (dad) is away, so they are staying put until then. Give it a week I'd say.
-Ryan
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IamOiman (original poster)
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#27: Post by IamOiman (original poster) »

I decided to use the cleared main bench for testing. I brought the machine upstairs then mounted the group after I sort of struggled moving it with the group attached the first time. 3 liters of water will fill the boiler to the top of the visible glass, and I marked about where the element lies in the boiler. In practical use I intend to never let the water level be visibile (ie it's always filled above the visible part).





I turned it on yesterday but I had two leaks to address after reaching 0.4 bar, the lower sight glass fitting and group gasket. I cried a bit for the latter as it was not fun taking off the big fitting. I had to drain the boiler, take off the sight glass, and bring the machine up the edge of the table so I could unscrew the thing (held in place by hand so the machine does not tip over mind you). It was a two person job to get that fitting off and on with better applied loctite 55 (the original loctite was clump on two threads so I did not apply properly). I redid the group gasket without too much fuss.




Today I was able to bring the machine to full pressure (1.1 bar). There was very minor leaking with the wobbler weight that I will address when the machine is cooled off but everything else was buttoned up without issue. I pulled a shot with much better results, and I did not need to use a Fellini. I guess when I was originally testing the boiler I did not have the pressure very high and I did not change anything with the group, grind, or dose.





I pulled another shot for good measure, and hopefully I can continue using the machine tomorrow/Thursday.




The group takes 3-4 minutes to release the excess air from the portafilter, and if I remove it any sooner I get portafilter sneeze just like on my Gaggia LL/Tell. Kind of annoying but the shot quality makes up for it 8)
-Ryan
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IamOiman (original poster)
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#28: Post by IamOiman (original poster) »

After seeing how well behaved the Classica was yesterday I installed all of the body pieces (cup tray, body panel, front brackets) and I gotta say it looks pretty good 8)







I also got the water mains hooked up so I don't need to take off the lid every so often to fill the boiler from the top. I just needed a 1/2 to 3/8 BSP adapter. So far the machine itself is a little difficult to use with anything but a bottomless pf due to how high the espresso falls and drifts from the spouts, but that's ok. The fact it can even pull espresso is good enough for me to ignore the little quirks. It will also be my main driver for a few weeks since I already have it at my bench. I am not sure if I will try milk drinks on this machine, but we'll see.


Provided the machine acts well enough for the next few days I will mark this project as Finished. Of all the machines I've worked on this one I believe is among the most important, and the fact it can produce such good espresso even 70 years later is incredible to me, even more so the good condition of the machine after cleaning it up. I will not have too much more monologuing with this thread now. 8)
-Ryan
Using a spice grinder violates the Geneva Convention
LMWDP #612

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