1957 Urania 2nd gen refurb - Page 5

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Lambretta58
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#41: Post by Lambretta58 »

When I was working on heavy equipment we always had broken off studs. We would weld a nut smaller than the stud and use an impact on it. These were 1/2"-1" studs and sometimes this was the only way to get them out due to space limitations.

Can't see why it wouldn't work for you also. It just gets a little tricky with small diameter studs. You could tig them. We used a 7018 stick electrode.
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mingiunate (original poster)

#42: Post by mingiunate (original poster) »

After a few more attempts at removing the studs myself, I called in the pros. A local machinist was able to extract the final two studs for me, and this cleared the way to begin soaking the boiler in citric acid and cleaning it up.





After about 8 hours of soaking, most of the scale was removed. There are still some harder deposits left at the bottom, but I think this is might have to be good enough. Please chime in if I should keep soaking or if there anything else I should be doing prior to sealing this up to make sure the water that will eventually flow thru this boiler is fit for consumption?

Before:


After


As for the outside of the boiler. The soak started to remove the after-market layer of zinc paint that was on the boiler, and I used some scotch brite pads to finish it off. I don't plan to do much else on the outside - besides a basic cleaning. I think it looks pretty good as-is with the copper body and brass ends and fittings.




mingiunate (original poster)

#43: Post by mingiunate (original poster) »

I tried to get as far as I can with the reassembly before needing to put this project down for about a month or so while I head out of town.

The boiler was reassembled, and installed onto the frame with all of the original copper pipes. I replaced the heating element with a 110v version, and a new gasket.




To reassemble the group I used the Astoria 130mm spring. Curious if others have feedback - but this looked like the closest spring to the original which was just too rusted to reuse. https://www.tse.at/us/shop/product_info ... toria.html


Besides new gaskets, I replaced the shower screen and kept all of the other original parts (bearings, washers, etc) Also worth noting is that without the preinfusion piston/plunger, the nut at the top of the group was sealed with an M4 brass screw and a o-ring. The bottom part of the preinfusion mechanism had a weak spring and gasket - but it feels like it could have just been left out altogether. I would love to know if others have seen this as a stock factory configuration.


The water and steam valves were reassembled with new gaskets - not much to say there. The valve shafts need three of 15.5x7.5x4mm gaskets, which I'm waiting for a delivery on.





When I return, left to do are:
  • Finish installing the water knob and steam levers and manometer
  • Wire up the heating element and the electrics to power the Neon. Can anyone point me to a good 101 with considerations for wiring up the element?
  • Desolder the steam and water pipe fittings from the original badly bent pipes and attach to new ones. I'll have to figure out how to nickel/chrome plate them. Apparently these Urania's use 3/8" copper pipes (which just so happen to measure 9mm :shrug:) while modern pipes are all 8mm.
  • Test, troubleshoot, test
The remaining items on my list of optional side quests include:
  • hooking up a mercury pressostat.
  • finding a few backsplash stickers - no one seems to carry the 'Minimo' and 'Massimo' stickers that are approx 40mm wide, all the one's I've seen are much smaller
I'd also love to know what people's thoughts are on some of the more modern safety features: vacuum breaker, OPV, pressostat. My current thinking is to leave this as stock as possible; It will really only ever make a few shots a day max and always be under supervision - no timers or remote starting.

Marcelnl
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#44: Post by Marcelnl »

I got some stickers here, they have white and blue (E61) (and a wealth of other parts)
https://www.drtradingshop.nl/a-37195224 ... escription

I also went with the Astoria spring at TSE but have not yet installed it as the original was crusty but OK to use IMO.

the pipes I replaced were 8mm, although I would not read anything in that in a machine this old and the fact that Italian factories are known to have used whatever was available in them days post war.

Did you contact Thijs (Brooks) he had steampipes made ( I may have mentioned that before, as I vagely recall he stopped doing that)
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IamOiman
Team HB

#45: Post by IamOiman »

Wobbler weights work fine, just don't let the machine move suddenly while under pressure :D . With a gasket between the metal pin and the valve holder that screws into the boiler they can work just as well as the modern ones. Safety valves work fine, but if you really like to go old school the modern stuff is easy enough to switch out if you are concerned. From how it sounds you don't intend to make this a daily driver but more for specific times


I like vacuum valves so no vacuum occurs when the machine is cooling down, which is also a big cause of the old manometers not set to 0, but perhaps 0.1-0.4 bar. It's fine to not have one if the machine is on 24/7 though in theory, although I try to fit a vacuum valve on all my machines anyways.


Mercury pstats do work well and are simple, but I personally refrain from them on my 110V machines (which is most of them for me) with the higher current over 220V. Otherwise I would be more inclined to try them out. Like the vacuum and safety valve it can be switched out with mecury to modern or vise versa when you feel like it withut too much hassle. I usually use Sirai 20A pstats, model P203/T01 20A. I only source them from eevad now since they are so cheap there even with shipping

https://www.eevad.com/en/sirai-pressure ... 75180.html
-Ryan
Using a spice grinder violates the Geneva Convention
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mingiunate (original poster)

#46: Post by mingiunate (original poster) »

Marcelnl wrote:I got some stickers here, they have white and blue (E61) (and a wealth of other parts)
https://www.drtradingshop.nl/a-37195224 ... escription

I also went with the Astoria spring at TSE but have not yet installed it as the original was crusty but OK to use IMO.

the pipes I replaced were 8mm, although I would not read anything in that in a machine this old and the fact that Italian factories are known to have used whatever was available in them days post war.

Did you contact Thijs (Brooks) he had steampipes made ( I may have mentioned that before, as I vagely recall he stopped doing that)

I did reach out to Thijs - and he did confirm he longer makes steam pipes, but I will post my plan for the steam pipes shortly. The e61 sticker sets don't have large enough Min/Max stickers (~40mm), as well as the older carico/scarico stickers - in any case I think I was able to source what I needed for now from another member.

mingiunate (original poster)

#47: Post by mingiunate (original poster) »

IamOiman wrote:Wobbler weights work fine, just don't let the machine move suddenly while under pressure :D . With a gasket between the metal pin and the valve holder that screws into the boiler they can work just as well as the modern ones. Safety valves work fine, but if you really like to go old school the modern stuff is easy enough to switch out if you are concerned. From how it sounds you don't intend to make this a daily driver but more for specific times

I like vacuum valves so no vacuum occurs when the machine is cooling down, which is also a big cause of the old manometers not set to 0, but perhaps 0.1-0.4 bar. It's fine to not have one if the machine is on 24/7 though in theory, although I try to fit a vacuum valve on all my machines anyways.


Mercury pstats do work well and are simple, but I personally refrain from them on my 110V machines (which is most of them for me) with the higher current over 220V. Otherwise I would be more inclined to try them out. Like the vacuum and safety valve it can be switched out with mecury to modern or vise versa when you feel like it withut too much hassle. I usually use Sirai 20A pstats, model P203/T01 20A. I only source them from eevad now since they are so cheap there even with shipping

https://www.eevad.com/en/sirai-pressure ... 75180.html
Does the gasket on the wobbler help with noise or is there some other benefit? This looks like a good idea, and I'll add this to the to-do list.
I will look into vacuum/safety valves - I can see how these add safety and convenience to the operation.

I thought I saw somewhere the mercury pstats were rated for 20a, is that right or is there any way to tell? But I do agree that 110v elements might be pushing it (my 1500w element draws 13a).

mingiunate (original poster)

#48: Post by mingiunate (original poster) »

I'm back from a break, and have begun the final push to get this restore completed.

First up is planning out the electrics. I replaced the orig 270v 1400w element (which I discovered still works after a very long soak in citric acid to remove the scale) with a 110v 1500w element. For the moment, I've decided I'm going to skip installing a pressostat, and instead hook up a double toggle. However, I need to decide on the exact wiring configuration for the elements - so I ran some numbers to see what warmup times would look like under various configurations:

It would be great to get a sense check for these numbers, but essentially assuming 4L of water in the boiler (80% full) and about 20kg of metal (between the boiler and the group) heated up 80 degrees (from 20C to 100C) it would need about ~2m joules. At 500, 1000, and 1500 watts, that would take 65, 33, and 22mins respectively. Does this roughly check out with real-world observations?

My thoughts are to configure the double toggle as Lo/Hi, where the Lo position only keeps the 500w element on, and the Hi position turns the 1000w or both elements on. Once up to temp, will the 500w element be enough to maintain temperature? I sketched out the wiring for these two options, please let me know if you think there is an error in them:




In the 1500w configuration theres about 13a drawn, which feels like it might be on the high side as its close to the 15a limits on the breaker, so I'm tempted to try out the 1000w configuration first, I'm just not sure if I'll regret the extra 10mins of warmup time. I'd welcome any feedback on this proposed wiring setup.

old element:

new element

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IamOiman
Team HB

#49: Post by IamOiman »

mingiunate wrote:Does the gasket on the wobbler help with noise or is there some other benefit? This looks like a good idea, and I'll add this to the to-do list.
I will look into vacuum/safety valves - I can see how these add safety and convenience to the operation.

I thought I saw somewhere the mercury pstats were rated for 20a, is that right or is there any way to tell? But I do agree that 110v elements might be pushing it (my 1500w element draws 13a).
The gasket helps seal the wobbler weight from releasing steam too early, so I guess by not letting the steam escape it makes the weight a little quieter. The bulbs are rated at least 10 amps but the wiring going from the bulbs to the ceramic block where you connect the rest of the wiring is unknown, which is why I do not usually use mercury pstats on 110V (also it's not allowed to be used inside the house).

12-13A is perfectly fine on a 15A 120V circuit. The circuit is designed to be used constantly up to 80% of the rated current (12.5A) as a continuous load

The National Electric Code defines a continuous load as anything in operation at its maximum rated current for greater than 3 hours. All of my espresso machines will probably not sustain an electrical load this long even during initial warmup

What this means is you would be able to max out the 15A 120V rating of 1875W rather than the 80% load for safety purposes of 1500W since the machine is not always on/heating the boiler, and operates on a duty cycle. But even with the 80% restriction you will still be fine even if the heating element on was constantly without turning off.

The heating time sounds about right but that is just until the machine reaches operating pressure. The group still needs to warmup after that which adds 15-20 minutes for a Zodiac group. Dippers need more time
-Ryan
Using a spice grinder violates the Geneva Convention
LMWDP #612