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Thread: Londinium L1 luxe Edition - Evolution

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    Londinium L1 luxe Edition - Evolution

    This is going to be a long one, folks. Bear with me.

    So for those that are wondering what became of Andy's Londinium - it made it's way to my workshop shortly after the L1 Luxe First Look thread descended into slander and wild accusations of ulterior motives, in the hope that we could turn it into something that performed as good if not better than was advertised.

    That review was contrary to most of what was being written about the machine in the early days, but as I can now see, was pretty much on the money. As soon as I got it onto the bench I had to agree, the thing was just not that well finished for an object that was sold as a 'Luxe' with all that the word implies, and all that was advertised.

    First of all, let me preface by saying, I have no particular interest in slagging off Londinium, Reiss or anyone else that extols the virtues of the machine. After all, he just inadvertently gave me a source of income.

    He has done really well to bring his creation to market and it's very easy to sit on the sidelines and criticise his efforts, but as Chopinhauer I think said in the other thread, it just reinforces that it's no trivial task to design, construct, market and sell a high end espresso machine. I wish I could do it. Maybe I will one day, but not any day soon.

    My one major gripe is that many things have been said publicly on the Londinium blog which are just plain silly, full of hyperbole and pseudo-science that in my opinion is designed to bamboozle the non-technical reader.

    In no particular order, some below issues that Andy and Chokkidog observed and I agree-

    -Dings in boiler, leaky fittings and poorly applied lacquer

    -Poor finish of laser-perforated vents etc, ie. not finished post-cut to remove scorch marks and burrs

    -Over-tightened fasteners that have permanently distorted panels

    -Inattention to design issues with poor ergonomics and internal heat buildup (switch placement, vent behind the water tank)

    -High tolerances in panel folds and poor alignment during assembly leading to user annoyances (drip tray impossible to remove when full)

    In all fairness some of these issues are not unique to the L1, and many Italian machines are poorly finished if you look hard enough, but they are not labeled 'Luxe'. The bottom line is that this machine is not even close to being in the same league as a Rocket in terms of quality fit and finish and attention to detail.

    So, to get on with it. Andy brought it round and gave me carte blanche to do whatever I thought needed to be done, and invoice him for the parts and labour accordingly, within reason! My first task was to figure out what was going on with the seemingly inconsistent results in the cup. By this stage there was plenty of data coming in from customers in the States with mixed reports about temperature stability - manifesting itself in some machines as a seemingly random drop in idle temperature measured at the exterior surface of the group, with correspondingly cool shots.

    At this stage, the erroneous measurements were attributed to the way those users were pulling shots, somehow delaying the downward pull and pushing air into the thermosyphon. Bollocks, says I, and carried on logging measurements. I was definitely seeing the dip in the group temps. In normal circumstances, the thermosyphon works really efficiently and as soon as there is steam pressure in the boiler the group temperature comes up really quickly and reaches an idle temp in the low 80's C. However, sometimes it would not recover after a shot, and keep falling over until a quick flush was performed, or self-righting after a longer delay.

    In short, I found that the group temps and resulting shot temps were perfect, as long as you could see the group temp starting to drop and reverse it with a quick flush. Occasionally it worked flawlessly by itself, often it didn't. So, the question became, why does this thermosyphon / heat exchanger have issues that conventional ones don't seem to have? As far as I am concerned, the answer lies in the source of water to the HX loop - namely the boiler. In a standard HX, the injection pipe that feeds the HX tube comes from pressurised cold mains water, or a vibe pump / tank, with a check valve in place to prevent backflow. Thus, when cold water is heated inside the HX, the thermal expansion of the water creates pressure as the system is a closed loop. Pressure increases up to the limit of the expansion valve, commonly 11 bar.

    In the case of the Londinium with it's open thermosyphon fed from the boiler, there is no expansion and associated pressure increase as the boiler pressure and the thermosyphon pressure are always equal - there are no intervening valves, just a short length of copper pipe. This is not the first machine to work this way - my guess is that it's a Faema design (the Lambro for instance) but I have also seen pictures of Pavonis, Astorias and of course the QM Achille that work in the same way.

    So, my theory was that if the thermosyphon loop was turned into a true HX (ie a separate hydraulic system), everything should work properly and the operating pressure in the HX would increase due to the thermal expansion of cold water entering the system. So I blanked off the boiler connection and fed mains water into the HX injector, with a one-way valve, expansion valve and gauge. And guess what, it worked flawlessly with rock solid group idle temperatures shot after shot, contrary to a statement by Reiss about how that configuration would be a total disaster.

    So at that point I could have gone back to Andy and said you have to plumb the machine directly into the HX to get it to work, but clearly that wasn't going to work as Andy paid for a tank machine, and damn it thats what he wanted. By this stage Reiss had got his act together and offered a retrofit kit to add a one-way valve between the boiler and the TS tube to turn the TS into a closed loop. The key detail he missed out on was that in such a setup you need to be able to let the excess pressure escape other than by doing potential damage to pipes and seals... this is why we have expansion valves. He got there in the end and the current configuration is a combination Fluid-o-tech one-way and expansion valve.

    At this point, the only viable solution seemed to be to drastically reconfigure the way the thermosyphon worked, and gain effective control of the group temperature. A cartridge heating setup similar to the Strega was investigated, but unfortunately there wasn't enough room in the group casting to get away with it.

    Eventually I settled on shoehorning a small volume brew boiler directly behind the group, with short, rigid pipes attaching it to the TS ports. The one-way valve and expansion valve was retained, as well as the system of feeding it via boiler pressure. The control loop is very effective as the heat source is only about 60mm from the group, and water is directly circulated to the group by straight 12mm brass pipes with no restriction, and in operation the brewing temperature is completely discrete from the steam boiler, as it is in conventional dual boiler machines.

    While I was redesigning the innards, I also did the following:

    -Replaced Sirai pressurestat with an Expobar with a much tighter deadband (this is now a moot point except for the space saving)

    -Moved mains switch to a more sensible location below the gauge

    -Re-aligned the front panel and modified the drip tray to fit properly

    -Machined the group sleeve to fit the E61 screen properly, so it bottoms out on the screen, freeing up about 2 mm of clearance in the basket

    -Vented the anti-vac valve into the tank so it doesn't fog up the glass panels

    -Stopped all leaks

    -Replaced stock tiny steam wand with cool-touch standard length unit

    There is still more work to do on the exterior, we plan to add a cup tray and vent the top panel but I am in the process of locating a stainless steel specialist to undertake this work, it goes well beyond my skill level/patience.

    I'm pleased to report the machine is behaving dare I say it as advertised, with a few added niceties and the wonderful ability to compensate for changes in ambient temperature or bean choice by adjusting the PID setpoint - Reiss got it right when he said that these groups are EXTREMELY sensitive due to the enormous surface area. Even walking past the machine can cause a movement of air that will suck one degree out of the group's thermal mass. Quite amazing that the TS works at all!

    Pictures of the work done so far to follow in the next post, I think this one's long enough, but I bet I've missed a few points that I wanted to expound on... oh well. I'll think of them soon enough.
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    The Boiler. My theory with the dings and the crazed lacquer around the autofill probe port is that they realised they had to change the alignment to prevent the probe bottoming out on the HX tube. So they resorted to a Birmingham Screwdriver. Perfectly fine, if it's not an objet d'art in a glass case.



    Similar heavy-handed treatment on the TS pipes. I didn't do it, I swear!





    Machining the flange for the brew boiler



    All sealed up



    Relocated pressurestat and safety valve to make room for the new boiler



    additional pipes fabricated and ready to run it up and bleed the air





    skimming a tiny bit off the sleeve to fit the shower properly



    small difference in the stack height of the spring / piston in the Londinium configuration of the CMA group (Londinium on the left). To the right is the '11 bar' spring, actually measures 9 bar, the Londinium 7.5.
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    This is epic... can you please give us an indication of how much this work costs to get done?

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    Relocated mains switch



    external PID box



    Internals finished

  5. #5
    TC
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    I have had the honour of admission to the inner sanctum to observe this transformation of Andy's machine day by day as Rick problem solved it and it was amazing to play with it over the last couple of weeks and to sample what it can reliably do now. There have been some incredible shots.

    All I can say is that I am awestruck by his level of technical expertise. We are lucky to have amongst us those who are prepared to push the envelope and are yet so humble about what it is they do.

    Stand tall Rick. This is incredible work.

  6. #6
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    aw shucks, thanks Chris

    Thankfully I have people such as yourself who can actually make coffee, pop in and tell me if it's working or not.

    Everything I know I have learnt from a certain reclusive master technician who is not seen around these parts much anymore, but can often be found roaming the wilds of Brunswick foraging for discarded IT equipment.

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    Senior Member skydragondave's Avatar
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    This is amazing.
    I'm just finishing a restoration of a CMA lever group machine with dip tubes, and wonder if adding a HX will improve stability with it.
    Is your brew boiler completely scratchbuilt, or is the body an off-the-shelf component?
    Thanks for documenting this modification and sharing it with us.

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    Senior Member Vinitasse's Avatar
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    c_m, your work is absolutely amazing and worthy of being in a museum of steampunk art... and that is meant in the best possible way!!!
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    Stunning work!

    For someone like me who works in an office pushing paper, it's quite humbling to see the work of a person who can design and engineer with such precision.

    Not sure the "Made in England" is relevant any more though...maybe "Made in Northcote" is more appropriate.?
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    TC
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    Quote Originally Posted by skydragondave View Post
    This is amazing....
    Is your brew boiler completely scratchbuilt, or is the body an off-the-shelf component?
    It's a souped up Silvia boiler sdd,

    You should see what Rick did with 3 of 'em to create his 19kg, dual boiler PID Silvia. It's also an astonishing machine!

    Quote Originally Posted by Jonathon View Post
    Not sure the "Made in England" is relevant any more though...maybe "Made in Northcote" is more appropriate.?
    Last I heard, Andy had dubbed it The Australium.
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    Loving the craftsmanship there! Very nice work.

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    Quote Originally Posted by Talk_Coffee View Post
    It's a souped up Silvia boiler sdd,
    Heh, I thought I recognised that boiler ;D

    Awesome work

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    Outstanding!
    Well done CM

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    Heh, in the context of this thread I feel it prudent to throw this in here;
    LONDINIUM I: right from day 1 from Londinium Espresso

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    TC
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    ....We admit that we got it wrong, so now we're reverting to the original wrong one....

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    I particularly like this bit thanking the "...large number of customers that have donated their time to help us get to the bottom of this issue" ;D

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    Senior Member Bosco_Lever's Avatar
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    And it starts all over again!

    How about we get back on topic, and stop the L1 bashing. To be honest, everyone is over it. Instead you should be joyful of the renewed interest in Levers which made it possible for the product to come to market; hopefully others will follow.

    Having a Retailer make smug comments about certain products; is not a way to endear themselves to potential customers. I know of at least six people personally who have avoided doing business with a retailer; who is guilty of this syndrome.

    Back on Topic,

    Thank you Rick for sharing your work in such detail. As you said, not all espresso machines are finished to the same standard as a KVDW product, but they can still produce the goods (no reference to the L1).
    It is always nice to see the skill of Australian technicians showcased.

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    Senior Member SniffCoffee's Avatar
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    I'm curious whether the Londinium temp issues are perhaps due to the smaller boiler?

    Both the Bosco and Achille have large boilers (6 ltr and 4.5 respectively) whereas the Londinium has a 2.4 boiler. Would the larger boilers keep the temp more stable by allowing a better flow through the thermosiphon?

    Sniff

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    Quote Originally Posted by SniffCoffee View Post
    Both the Bosco and Achille have large boilers (6 ltr and 4.5 respectively) whereas the Londinium has a 2.4 boiler. Would the larger boilers keep the temp more stable by allowing a better flow through the thermosiphon?
    I gather the problem is the thermosyphon stalling out because the feed isn't high enough pressure to kickstart it after pulling a shot. Though I suppose a physically larger boiler would have a larger temperature gradient between the top and the bottom of the boiler so that might assist in preventing it from stalling in the first place.

    But I do not claim to be a fluid engineer ;D

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    Senior Member chokkidog's Avatar
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    Great post and pics of the work, Rick.

    Truly, the work of a master craftsman passionate about getting things right.

    I'm looking forward to seeing the beast again.

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    Thanks for your kind words and ongoing support Bosco. Much appreciated.

    JB- we don't much like the Achille on tank either. We have a current Achille project and the intention is to go dedicated plumbed first and then look at the thermosyphon loop as well as the HX anatomy.

    Rick and Phil will be involved in this one as well. If we can get it anywhere near the performance of Andy's machine, I'll be wrapped. I am confident that the machine is in good hands!

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    Quote Originally Posted by Talk_Coffee View Post
    JB- we don't much like the Achille on tank either. We have a current Achille project and the intention is to go dedicated plumbed first and then look at the thermosyphon loop as well as the HX anatomy.
    Fair enough sounds like it might just be endemic to tanked, boiler-fed HX systems then. I look forward to seeing the results ;D

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    Rick, Superb work and an excellent result ..A dual Boiler Lever !

    But could you explain one point.... as to the decision not to simply go with a low pressure pump feed to the HX in order to retain the tank supply..( if the mains feed was not acceptable) once you had a good solution to the stall problem. ?
    Quote Originally Posted by coffee_machinist View Post
    .....
    So, my theory was that if the thermosyphon loop was turned into a true HX (ie a separate hydraulic system), everything should work properly and the operating pressure in the HX would increase due to the thermal expansion of cold water entering the system. So I blanked off the boiler connection and fed mains water into the HX injector, with a one-way valve, expansion valve and gauge. And guess what, it worked flawlessly with rock solid group idle temperatures shot after shot,
    .....
    So at that point I could have gone back to Andy and said you have to plumb the machine directly into the HX to get it to work, but clearly that wasn't going to work as Andy paid for a tank machine, and damn it thats what he wanted.

    At this point, the only viable solution seemed to be to drastically reconfigure the way the thermosyphon worked,.........

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    Thanks everyone for your responses.

    B52, A HX that is driven by a tank / vibe pump is great if you have a means of switching on the pump when required, in a lever machine this is not easy. The strega achieves it with a microswitch hidden under the group cap that engages when the lever is brought down, but the lovely exposed group on the L1 makes this less than ideal.

    Another option was a pressure switch somewhere in the system to switch on the pump at 0 bar and switch off at say 2, but this has major reliability concerns for me. Or just a plain ol' toggle switch somewhere that would require the user to lower the lever THEN flick a switch to charge the chamber, but that was never going to fly.

    I would love it if there was a way to pressurise the feed to the group without the use of pumps or boiler pressure, with it's associated need for autofill to kick in on every second shot. Somewhat diminishes the beauty and simplicity of the lever principle. However, to my knowledge, mains water is the only way that's going to happen.

    The Victoria Arduino Athena and KvdW Mirage Idrocompresso are two machines that feature a true HX fed by mains water, there may be others.

  25. #25
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    Really nice work, Rick, thanks for posting it. A few questions:

    1. It appears that this machine is probably more temperature consistent than a stock L1, but was does the temperature profile look like? Since one of the lever machine's assumed advantages is its declining brew temperature profile, how does your modded machine's temperature profile compare with a stock profile? Have you logged and graphed it in order to compare?

    2. In that horizontal configuration, can you be sure that the Silvia boiler's heater element is covered with water? Seems like heater life will be significantly reduced if the upper portion of the heater is above the water level.

    3. What's the total electric draw during startup? I'm stuck with 110v here in the States, and this means the extra 6+ amps that a Silvia boiler normally requires could be a problem.

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    Hi Andy,

    Some pertinent questions, thanks!

    Re. the temperature profile, nothing much has changed. The design goal was to keep group idle temperature constant. Because the group is acting as a huge heat sink, there is still a large thermal gradient across from the brewing boiler to the front of the group. To achieve a peak shot temperature of 94 degrees C, the actual SV of the controller is about 105. As such, the brew water is shedding heat as soon as it hits the group in exactly the same way as if it were fed directly via the TS. There is no appreciable difference in the curve. With my scace set up to replicate 30 ml outflow over 30 seconds, you see an initial rise as the chamber charges, followed by a rise of approx two degrees C as preinfusion ends, then the classic taper off of circa. 4 degrees C as heat is absorbed into the group over 20 seconds ish. The longer the shot runs, obviously the more heat is lost. I am gathering data over the next few days, it was really stupidly cold in the workshop last week with ambient temperatures of 12-13 C. Not good for getting readings consistent with my previous data from the stock machine and the mains-fed HX.

    I'm pretty confident that there will be no adverse effect on the element with the boiler mounted such as it is. The brew boiler is kept saturated by the one-way valve on the inlet preventing backflow into the boiler. I have added a bleed screw to the top and will check in a few days whether there is any air entering the system. With the probe literally millimeters from the element, I don't anticipate any problems with overheating. I will most likely add a safety thermostat to the boiler before Andy takes delivery of the machine though, just in case the controller or SSR fails.

    I have swapped out the element in the steam boiler to a 1200W unit, so we have 1200W +1200W for exactly 10 amps. I would have preferred to go for say 1600 steam plus 600W brew but the extra power in the brew is not a bad thing to have. Steam performance is still excellent with the new pressurestat, although warmup times are extended a bit. It's a large boiler for 1200W, but definitely workable.

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    Member ASchecter's Avatar
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    Excellent. Sounds like this machine must be rather foolproof in making some terrific espresso. Again, thanks for posting your story.

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    Last I heard, Andy had dubbed it The Australium.
    Yep, banished to the colony and then made better...

    australium.com.au

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    Senior Member Vinitasse's Avatar
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    Quote Originally Posted by Andy View Post
    Yep, banished to the colony and then made better...

    australium.com.au
    Absolutely brilliant!!! :thumbup:

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    I have a question, Was the lacquer used at the factory just a standard clear lacquer applied straight to the boiler or is it a high heat formula? And how does it stand up over time?
    Thanks

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    Life-long Learner DesigningByCoffee's Avatar
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    Beautiful work Rick - a true work of art.
    And stunning photos!

    Matt

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    Quote Originally Posted by coffee_machinist View Post
    B52, A HX that is driven by a tank / vibe pump is great if you have a means of switching on the pump when required,.....

    Another option was a pressure switch somewhere in the system to switch on the pump at 0 bar and switch off at say 2, but this has major reliability concerns for me......
    ..
    Rick, i respect your decision and system design choice to configure a "dual boiler" machine,..it will open up many opportunities for brew temp adjustment.
    .......However, i dont understand your concern over the pressure switch system,.. had you wanted to retain a simplified cold pressure feed.
    Pumped water systems using pressure switches are very common in many "off mains" households throughout the world and have a very good reliability record. They are obviously designed with a "fail safe" configuration.
    Looking forward to some videos of this machine in operation. !

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    How often does the boiler fill from the tank? I was just wondering if cooling the HX return line with the boiler fill water might help maintain the flow in the thermosyphon loop?

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    Quote Originally Posted by MrJack View Post
    How often does the boiler fill from the tank? I was just wondering if cooling the HX return line with the boiler fill water might help maintain the flow in the thermosyphon loop?
    Well, since the HX is fed from the boiler, so the boiler must be topped up for every shot that is pulled.

    Yes, i also suspect there is a basic issue with maintaining the TS flow on the L1, and fundamentally its the result of a horizontal HX in the boiler, combined with a too short return leg from the group.
    ...Maybe just tilting the whole machine 10 deg such that the hot end of the Hx is a little higher may help !

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    I thought it was open to the boiler? In which case a Hx inside the boiler would seem a bit redundant with any geometry. The boiler does seem a long way from the group. Insulating the group feed would probably help also.
    Last edited by MrJack; 3rd August 2013 at 02:31 PM.

  36. #36
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    Quote Originally Posted by skydragondave View Post
    I have a question, Was the lacquer used at the factory just a standard clear lacquer applied straight to the boiler or is it a high heat formula? And how does it stand up over time?
    Hi Dave, to be honest I can't tell you much about the lacquer. It becomes slightly tacky at high temperatures, so where fittings have previously leaked it has peeled back a bit. As to the longevity, no idea. It's the last thing I would elect to coat fittings with that stand a reasonable chance of being undone in future, makes it impossible to fit metric spanners to anything without doing damage, as the lacquer adds thickness. The copper/brass Elektra Microcasa has a really durable clear lacquer that is high temp and I suspect also food safe, but no idea what product it is.

    Quote Originally Posted by blend52 View Post
    Rick, i respect your decision and system design choice to configure a "dual boiler" machine,..it will open up many opportunities for brew temp adjustment.
    .......However, i dont understand your concern over the pressure switch system,.. had you wanted to retain a simplified cold pressure feed.
    Pumped water systems using pressure switches are very common in many "off mains" households throughout the world and have a very good reliability record. They are obviously designed with a "fail safe" configuration.
    Hi B52, as you say pressure switches are not uncommon, but I would want to be convinced that it would work reliably in this application. The implication there is that I would have to trawl through the usual suspect's catalogues, Parker, Sirai, Mater, etc, to find a part that should theoretically do the job, then order a one off (stock in the country? Unlikely) test it in a real world application (with the sort of maximum pressure, switching frequency and ambient temperatures associated with this non-standard application), then if successful integrate it into the design.

    My reasons for going the way I did are quite simple. I know my solution is going to work, because the engineering principle is sound, I am using parts I am familiar with and they are proven in this application. I know how they fail, when they fail and why they fail so I have confidence using them. If I had prior experience with pressure switches for water feeds inside espresso machines, maybe, but I'm not prepared to explore it fully at this stage for a one-off project with a deadline.

    I doubt there is any simple modification that can be done to the way the HX in the L1 is set up that would improve stability. As far as I'm concerned it all comes back to that lack of pressure to drive TS activity after the temperature gradient between group and boiler drops. The fact that this issue seems to be confined to a few machines so far is baffling though.

  37. #37
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    I had a chance to hang around today and do some final temperature monitoring, so here is the data for anyone curious. The graphs show two measurements, the group temperature (in green) measured on the outside of the group, half way from front to back of the cylinder and slightly lower than higher and the shot temp / scace measurement (in red).

    In some graphs the group measurement is slightly lower, probably not enough heat sink goop applied. Consistency is the critical part, not so much the actual number. In practice there is a pretty clear relationship between shot temp and group idle temp, and I am always aiming for the shot temp. to fall between 90-95 degrees c. 84 seems to be the sweet spot for group temp.

    Ignore the spikes in the data, they are random voltages induced in the probe leads by the machine doing various things like running the pump or switching on the element and I have not been able to get rid of them. Shielded and grounded probes perhaps...

    The timescale is in minutes.

    1.


    This is what the prolonged stall looks like. First shot good, but then it just falls off and falls of and falls off until a flush sends things in the right direction again.

    Stock machine, pressurestat 1.3 bar, ambient temp. 17 degrees C, side panels off


    2.


    This shows that with a short flush before brewing, the shot temps are pretty tightly grouped.

    Stock machine, pressurestat 1.3 bar, ambient temp. 17 degrees C, side panels off


    3.


    Now we have the HX running on mains water, operating at around 7 bar. Pretty darn impressive stability.

    Mains fed HX, pressurestat 1.3 bar, ambient temp. 16 degrees C, side panels off


    4.


    This with the brew boiler fitted. I tried to simulate back to back shots followed by a rest followed by another back to back group.

    Brew boiler @95.5C SV, pressurestat 1.5 bar, ambient temp. 13 degrees C, side panels off


    5.


    Two shots over 5 minutes, curve almost identical. Sweet!

    Brew boiler @95.5C SV, pressurestat 1.5 bar, ambient temp. 13 degrees C, side panels off
    Last edited by coffee_machinist; 3rd August 2013 at 06:54 PM. Reason: formatting
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    Senior Member Vinitasse's Avatar
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    I like your work :-)

    VERY impressive!

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    Quote Originally Posted by coffee_machinist View Post
    I doubt there is any simple modification that can be done to the way the HX in the L1 is set up that would improve stability. As far as I'm concerned it all comes back to that lack of pressure to drive TS activity after the temperature gradient between group and boiler drops. The fact that this issue seems to be confined to a few machines so far is baffling though.
    What seems strange, is that your data (1) seems to suggest an increase in the temperature gradient between the group and the boiler over time (unless of course the boiler temp is also falling). From the pictures, and what blend52 said before, it seems that the feed and return lines in the thermosyphon are working against each other (significant cooling in the upward flowing feed line?).
    Perhaps the long flush merely adds momentum to the water in the thermosyphon (much like sucking on a hose in a normal syphon)?

    I don't really follow what you mean by lack of pressure, but it would be very interesting to see what the temperatures of the group feed/return were like. Shame you've already fixed it

  40. #40
    Site Sponsor coffee_machinist's Avatar
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    Just for the record, since the predictable vitriol is appearing on the Londinium blog.

    The short flush theory, suggested by me and others, 3 months ago in the H-B thread:

    All machines, even saturated boiler pump machines, will require some degree of thermal management. In my experience, the back of a hand against the group then a quick flush is a pretty effective solution to the problem
    Reiss on his blog / platform for launching personal attacks yesterday:

    we quietly took our time and discovered that a short flush is all that is required immediately after a shot and the LONDINIUM series of lever machines are as thermally stable as any other espresso machine architecture. sometimes it takes a long time to get to the bottom of an issue, but it is only in doing so that a simple and effective solution can be found; a 60mL flush after you pull your shot
    This, after revising the design twice, shipping parts to customers then saying the revisions are not needed, while promising to publish his own data which is still forthcoming.
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    Quote Originally Posted by MrJack View Post
    .... but it would be very interesting to see what the temperatures of the group feed/return were like. Shame you've already fixed it
    MrJ,.. If you havent already seen it, Rick , and others have previously posted TS flow temperature plots over on the HB forum.
    I believe that most of the L1's monitored in this way have clearly shown the TS flow to completely reverse at times after a shot.
    Last edited by blend52; 4th August 2013 at 01:38 PM.

  42. #42
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    Quote Originally Posted by coffee_machinist View Post
    Just for the record, since the predictable vitriol is appearing on the Londinium blog.

    I'm very proud to think that I may well be one of the "juvenile, interconnected petrified individuals..." referred to in this most recent of rants.

    I contacted Reiss very early in the peace to express interest in selling the machine because I too believed the hype that I read. I never received anything significant in the way of a reply. Once I saw photos of the prototype, I moved on.

    I am very glad that Reiss stuck to his model and sold them himself- having eyeballed the build quality and performance of this machine.
    I have always said that when someone feels they know everything, it's time to get out. I am the first to admit I have much to learn- and I learned a whole heap by watching Rick work.

    I have the luxury of doing business with people and companies I respect.

    Last edited by TC; 4th August 2013 at 01:52 PM. Reason: more info

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    Thanks for posting this. It is nice to see such dedication.

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    Senior Member Dragunov21's Avatar
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    To be fair, there's one thing that always bothered me about this whole saga; why didn't Andy simply take advantage of the highly-publicised no-loss/no-questions return offer?
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    Quote Originally Posted by Dragunov21 View Post
    To be fair, there's one thing that always bothered me about this whole saga; why didn't Andy simply take advantage of the highly-publicised no-loss/no-questions return offer?
    Great question and I look forward to the answer having read both this and the other locked thread. The machine might as well be called 'The Mudslingium' form here on in.

  46. #46
    CoffeeSnobs Owner Andy's Avatar
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    Quote Originally Posted by Dragunov21 View Post
    To be fair, there's one thing that always bothered me about this whole saga; why didn't Andy simply take advantage of the highly-publicised no-loss/no-questions return offer?
    Quite simply, I didn't know about the 30 day return else I would have claimed within a fortnight of it landing.

    I ordered the machine (which showed as in stock and available on the Londinium website) hoping it would arrive before Christmas as I would have a week to play with it. It arrived 2.5 months after ordering and during a really busy time at CS. It was taken out of the box, pissed water everywhere and I didn't get back to it for a fortnight when I decided to take it to Sydney with me in the hope that CS'rs at Beanology could have a good first play with it, I thought it would be a good publicity exercise for the Londinium but instead it ran for a couple of hours and started leaning again from different pipes so it got turned off. It came back to Geelong with me at the end of that week and sat in the box while I caught-up on orders and work. Chocidog was collecting an order and I offered him the chance to do a road test of it. By the time I got it back and asked Reiss what he could do to help it was 60 days after landing and he told me to go jump. http://australium.com.au/email.htm

    Call me gullible but when I bought this machine I was being told that it was temperature stable within minutes and every shot would be consistent without ever needing a cooling flush. I had no reason to think that was a flat out lie. When I queried some of these claims after using the machine I was told I'm the only one in the world with a problem, the machine was inspected by the owner of the factory and a whole lot of other rubbish.

    Today he is quoting that the feedback from "many" are driving his troubleshooting and he is now saying that a 60ml purge will help.

    The very expensive, Luxe, top of the line model that arrived here was nothing like advertised. It was a good first prototype and if I bought it as such (with a price to match) then it would have been a very different story we were telling.

    Anyway, this is totally off topic. This thread is about what has been done to improve what arrived here so lets keep it about that please.
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    Senior Member Dragunov21's Avatar
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    *EDIT* Sorry Andy, I posted before seeing your reply. Your choice if you want to nuke it, obviously, I just wanted to clarify my previous post.

    Mmm... I'd like to elaborate on my last comment, since it could read as "Don't like it? Send it back and shut up"

    From what I've seen, following the threads:

    - Andy got a machine that failed to meet his expectations (rightly so, it appears).
    - It appears the particular machine may have been a lemon (ie defective and not representative of Londiniums as a product line).

    At that point, the most obvious course of action (to me) would be to contact the manufacturer, ask if the performance/readings/cosmetic defects were significantly out of spec and return the machine (for replacement if the manufacturer felt the machine was a dud or for refund if it was found to be operating "correctly"). Lemons happen. It's a real bummer but it does happen despite best efforts.

    Instead, a scathing review was posted (I don't use scathing as a bad thing, necessarily) and the machine was modified, ad-hoc, to improve its performance. Without determining whether this particular machine was performing as intended no-one can make a determination as to whether the poor performance is the product or the particular example, and if the manufacturer is willing to absorb associated costs there's no reason I can think of not to give them that chance.

  48. #48
    Senior Member Vinitasse's Avatar
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    Quote Originally Posted by Dragunov21 View Post
    *EDIT* Sorry Andy, I posted before seeing your reply. Your choice if you want to nuke it, obviously, I just wanted to clarify my previous post.

    Mmm... I'd like to elaborate on my last comment, since it could read as "Don't like it? Send it back and shut up"

    From what I've seen, following the threads:

    - Andy got a machine that failed to meet his expectations (rightly so, it appears).
    - It appears the particular machine may have been a lemon (ie defective and not representative of Londiniums as a product line).

    At that point, the most obvious course of action (to me) would be to contact the manufacturer, ask if the performance/readings/cosmetic defects were significantly out of spec and return the machine (for replacement if the manufacturer felt the machine was a dud or for refund if it was found to be operating "correctly"). Lemons happen. It's a real bummer but it does happen despite best efforts.

    Instead, a scathing review was posted (I don't use scathing as a bad thing, necessarily) and the machine was modified, ad-hoc, to improve its performance. Without determining whether this particular machine was performing as intended no-one can make a determination as to whether the poor performance is the product or the particular example, and if the manufacturer is willing to absorb associated costs there's no reason I can think of not to give them that chance.
    Put your money where your mouth is and give it a go then.

    I look forward to your first review.

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    Quote Originally Posted by MrWhite View Post
    Great question and I look forward to the answer having read both this and the other locked thread. The machine might as well be called 'The Mudslingium' form here on in.
    I see from your profile picture that you have a GS3. At the time of purchase Reiss was claiming that people were replacing their GS3's with these... I don't know who those people were but they certainly didn't get the same coffee from the Londinium and GS3 as I do. For the record, my GS3 is firmly on the bench both at work and at home.

    This has nothing to do with slinging mud, it was just honest user experience. I also notice that most of the people defending the Londinium don't own one or at least don't own a Luxe and are forming their opinions based on words on an internet page.


    Quote Originally Posted by Dragunov21 View Post
    *EDIT* Sorry Andy, I posted before seeing your reply. Your choice if you want to nuke it, obviously, I just wanted to clarify my previous post.

    Mmm... I'd like to elaborate on my last comment, since it could read as "Don't like it? Send it back and shut up"

    From what I've seen, following the threads:

    - Andy got a machine that failed to meet his expectations (rightly so, it appears).
    - It appears the particular machine may have been a lemon (ie defective and not representative of Londiniums as a product line).

    At that point, the most obvious course of action (to me) would be to contact the manufacturer, ask if the performance/readings/cosmetic defects were significantly out of spec and return the machine (for replacement if the manufacturer felt the machine was a dud or for refund if it was found to be operating "correctly"). Lemons happen. It's a real bummer but it does happen despite best efforts.

    Instead, a scathing review was posted (I don't use scathing as a bad thing, necessarily) and the machine was modified, ad-hoc, to improve its performance. Without determining whether this particular machine was performing as intended no-one can make a determination as to whether the poor performance is the product or the particular example, and if the manufacturer is willing to absorb associated costs there's no reason I can think of not to give them that chance.
    Mmm... I'd like to elaborate on my last comment, since it could read as "Don't like it? Send it back and shut up"
    Yeah, I read it something like that.

    At that point, the most obvious course of action (to me) would be to contact the manufacturer, ask if the performance/readings/cosmetic defects were significantly out of spec and return the machine (for replacement if the manufacturer felt the machine was a dud or for refund if it was found to be operating "correctly")
    there's no reason I can think of not to give them that chance
    Yep, that is exactly what I did. http://australium.com.au/email.htm

    Instead, a scathing review was posted
    No, an independent review was posted. I was so angry that I was sucked in that I've still not written a review as it will be far more critical and truly scathing as it was my $4000 I spent on this half baked machine. I think Chocidog was very soft and actually missed a few things that I thought were very poorly done (and have been fixed in the Australium).

    I still might do a review one day but mostly any mention of the original machine and the process makes my blood boil, I'm way too busy (yes, still at work now) to write a review or continue these discussions.... ergo by last comment of:

    Anyway, this is totally off topic. This thread is about what has been done to improve what arrived here so lets keep it about that please.
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  50. #50
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    Quote Originally Posted by Dragunov21 View Post
    Without determining whether this particular machine was performing as intended no-one can make a determination as to whether the poor performance is the product or the particular example
    Ah, now that's the crux of the matter. There is now a fair bit of data out there on the interwebs, generated both by folks who feel very strongly that they have a problem with their machine, and those that feel very strongly that they don't. I have seen data of stock machines behaving badly (including our Andy's - the above data was generated before any modifications were done, not even changing the pstat setting), and data of stock machines behaving well (Kfir, FransG on Home-Barista).

    From day one when AndyS put his findings up on a UK forum and was thoroughly castigated for it, there have been numerous theories put forth by Reiss and others, ranging from moving the lever too slowly, to inadequate lubrication on the seals, to changing the pressurestat setting, to now a prolonged preinfusion time. It's clear that no one really knows what's going on, including Fracino, or we would not have seen a revised one-way valve configuration at all. It's also clear from recent posts on the Londinium blog, that Reiss now acknowledges there are issues with some machines as regards the TS stall phenomenon.

    What gets me though is that there is no inherent complexity or possibility for variation in the construction of the machine, so why should most perform admirably when a small number don't seem to - it's not like the PID settings have been altered, it's all simple mechanics as Reiss says. Sure, there are complex fluid mechanics at work inside the TS that go way beyond my knowledge, but the machines should all work perfectly or they should all be stalling.

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