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  • 392392
    replied
    Originally posted by noidle22 View Post
    I'm afraid it's not good news.

    My primary concern about the machine was realised. The whole group head is completely isolated from the thermocoil and is made of plastic.
    It is fed by hot water from the thermocoil that has to travel through a solenoid valve and some tubing before getting to the group. There is no way to maintain any sort of reasonable thermal stability.

    The portafilter is surprisingly high quality and is stainless steel, it seems as though they have taken inspiration from La Marzocco in this regard. The shape of the portafilter itself along with the spouts attached with an o-ring fitting rather than a conventional thread. The problem with this big heavy portafilter is that it makes it quite hard to fully heat up. Leaving the handle locked in the machine doesn't heat it up at all (due to plastic group/no thermal connection to thermocoil) and it needs to be ran under hot water for quite a while to get hot.

    The next problem we face is pressure. Fortunately, the gauge is simply teed off the water line to the group head so it was easy to fit a gauge from a BES900. I brewed a shot and watched the gauge. The graduations on the gauge end at 13 bar, I've never taken one of them even that far. The needle kept going and stopped near 6 o'clock, I would assume somewhere around 17-18 bar. Not good.

    The pump is one I have not seen before. It's just attached through a safety valve to the cold water line to the thermocoil, no sort of pressure control at all. Fortunately there was just enough space that I could fit an over pressure valve from a BES900.
    After some adjustments I was able to get consistent pressure at the group. I set it to peak around 10.5 bar and found that it would drop to around 8 by the end of the shot.

    The espresso was definitely drinkable at this point but lacked any sort of body. There's just no way to improve the thermal stability and this is the real problem. This is the problem you are having with your sour shots Gil80, you have likely nailed the grinding, dosing and tamping but the machine is letting you down. Pair the lack of thermal control with your machine still cranking out 17-18 bar through the puck, you don't have a chance.

    Also one more issue re: water coming mostly from the front of the shower screen. I took the screen off and the output from the group is directly at the front of the screen, right where you see most of the water dripping in your video. The screen is also of poor design and quality so it does a bad job of distributing the water.
    Many other domestic machines also have water exit the group from a hole but they don't suffer as much as this machine does. I think that this is because of the way the water is delivered to the group. The tube feeds directly down through the hole and is not diverted or restricted in any way so it just comes out at full force. Most other machines have a passage or pipe that the water runs through before exiting the group, making it less of a direct jet of water straight down.

    That covers most of it, there's some other issues that I found but aren't as noteworthy. If people are interested I can write it up.

    [ATTACH=CONFIG]22365[/ATTACH] [ATTACH=CONFIG]22366[/ATTACH] [ATTACH=CONFIG]22367[/ATTACH] [ATTACH=CONFIG]22368[/ATTACH] [ATTACH=CONFIG]22369[/ATTACH]

    Some fine detailed work there; Have to say i was tempted to give the machine a shot (pun not intended).
    I know you save me some coin there.

    Leave a comment:


  • Dimal
    replied
    Terrific stuff noidle22...

    Hope you can write off the cost of this experiment to at least get something back for your generosity...

    Mal.

    Leave a comment:


  • Gil80
    replied
    Thank you for your efforts and help.

    I'll try to refund it.

    Leave a comment:


  • 338
    replied
    Great review NoIdle, you have probably saved a few people.

    Leave a comment:


  • noidle22
    replied
    Some more photos. As you can see, the machine is built on the Sunbeam EM4820 chassis. The water tanks and drip trays are identical.

    Click image for larger version

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  • noidle22
    replied
    I'm afraid it's not good news.

    My primary concern about the machine was realised. The whole group head is completely isolated from the thermocoil and is made of plastic.
    It is fed by hot water from the thermocoil that has to travel through a solenoid valve and some tubing before getting to the group. There is no way to maintain any sort of reasonable thermal stability.

    The portafilter is surprisingly high quality and is stainless steel, it seems as though they have taken inspiration from La Marzocco in this regard. The shape of the portafilter itself along with the spouts attached with an o-ring fitting rather than a conventional thread. The problem with this big heavy portafilter is that it makes it quite hard to fully heat up. Leaving the handle locked in the machine doesn't heat it up at all (due to plastic group/no thermal connection to thermocoil) and it needs to be ran under hot water for quite a while to get hot.

    The next problem we face is pressure. Fortunately, the gauge is simply teed off the water line to the group head so it was easy to fit a gauge from a BES900. I brewed a shot and watched the gauge. The graduations on the gauge end at 13 bar, I've never taken one of them even that far. The needle kept going and stopped near 6 o'clock, I would assume somewhere around 17-18 bar. Not good.

    The pump is one I have not seen before. It's just attached through a safety valve to the cold water line to the thermocoil, no sort of pressure control at all. Fortunately there was just enough space that I could fit an over pressure valve from a BES900.
    After some adjustments I was able to get consistent pressure at the group. I set it to peak around 10.5 bar and found that it would drop to around 8 by the end of the shot.

    The espresso was definitely drinkable at this point but lacked any sort of body. There's just no way to improve the thermal stability and this is the real problem. This is the problem you are having with your sour shots Gil80, you have likely nailed the grinding, dosing and tamping but the machine is letting you down. Pair the lack of thermal control with your machine still cranking out 17-18 bar through the puck, you don't have a chance.

    Also one more issue re: water coming mostly from the front of the shower screen. I took the screen off and the output from the group is directly at the front of the screen, right where you see most of the water dripping in your video. The screen is also of poor design and quality so it does a bad job of distributing the water.
    Many other domestic machines also have water exit the group from a hole but they don't suffer as much as this machine does. I think that this is because of the way the water is delivered to the group. The tube feeds directly down through the hole and is not diverted or restricted in any way so it just comes out at full force. Most other machines have a passage or pipe that the water runs through before exiting the group, making it less of a direct jet of water straight down.

    That covers most of it, there's some other issues that I found but aren't as noteworthy. If people are interested I can write it up.

    Click image for larger version

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  • noidle22
    replied
    I hope that I can fit a group head pressure gauge onto it, alternatively I have a few different pressure gauges that I hope are compatible with it. This will at least show what sort of pressure it's making.

    My other concern with it after reading your previous posts is that it is indeed not extracting hot enough. Sour tasting shots, even after isolating all variables, can mean a low brew temperature.
    I would think the thermocoil is heating correctly but the suspected isolation between it and the group may be causing some problems.

    I guess we'll find out tomorrow.

    Leave a comment:


  • Gil80
    replied
    Hahahaha

    I actually laughed reading your post.

    Kudos for the dedication and devotion!

    I can't wait to learn what you've figured out.
    That's going to be very interesting.

    Thanks for all the help.

    One thing that popped to mind is that the beans I bought have fruity profile to them which is probably higher in acidity and therefore perceived as more sour.

    I'll try to use nutty, chocolaty profile beans and see what comes out of it.

    Since I returned to use the pressurised basket, wow the creama it produces... But it also accentuate the sourness.

    Leave a comment:


  • noidle22
    replied
    Originally posted by Gil80 View Post
    I'll try to refund everything
    I was in Aldi today and there was two machines left on the shelf. I asked a girl if that's the last of them or if there was more out the back. She said that's the last of them. They get discounted after 6 weeks on sale so they weren't going to last.

    I did the rational thing of course, left the store and left the machine behind as spending $300 on something just to tear it apart immediately would be a terrifically stupid idea now wouldn't it......


    No, you're right, it's a GREAT idea. Bought the thing, I'll get into it tomorrow and see what I can make of it. I'll post here as soon as I can and you can make a judgement from there if you want to return yours or not. I also have a Breville BES840 in at the moment so I can do a side by side comparison.

    Leave a comment:


  • Gil80
    replied
    I've tested a few shots over the weekend and I simply can't get it.

    I've followed everything suggested here. My hopper is 2/3 full. Did a few blank grinds so the grinder will set it in with the burrs and just warm it up. I did it every time I had to change the settings on the grinder.
    27sec, 36g yield. Coffee is sour af.

    I'm down to grinder setting 3.
    Looks like it's still pouring out quickly, mostly through the end of the pour when it's hitting the 20g it gets quicker.
    1 week old beans, so they are still considered in the 'fresh' zone.

    I'm trying to be as consistent as possible with everything and change one thing at a time.
    I pre-heat everything that needs pre-heating.

    I clean and measure and time and you name it.

    Coffee comes out sour.

    I did order a Rancillio 58mm 18g basket but I doubt it will be a game changer from the VST, I doubt it will be OK just because of a basket change.

    I am returning my VST to the shop today and just wait for the Rancillio basket to arrive from ebay. Till then I'll have to revert to the pressurised basket.

    Other than the basket, I'm out of ideas. It could be that this machine pumps out 19 bar no matter what.


    I think I can understand now why people just buy capsule espresso machines
    I knew it's going to take a bit of time to get the grinder settings and pour time just right for the beans, but I never thought it's going to be virtually impossible. I could still be biggest variable and I just can't figure out when I hit the right dial settings or it's actually crappy coffee equipment + beans combo.

    If the basket I'll get from eBay won't help to achieve a nice espresso cup, I'll try to refund everything and just stick to my V60/Aeropress and no more espresso for me :/
    Last edited by Gil80; 3 June 2019, 12:49 PM.

    Leave a comment:


  • Barry O'Speedwagon
    replied
    Originally posted by Gil80 View Post
    But I'm the only one drinking coffee, this will make the majority of the coffee go bad because I expose most of it to oxygen, isn't it?

    .
    You can always return the unused beans to the ziplock bag at the end of the session. Given that you are using very, very fresh beans there shouldn't be a problem with staleness.

    Leave a comment:


  • Gil80
    replied
    Yep, agreed. I bought a Rancilio 58mm*Filter Basket 18g from eBay.

    I'll have to wait for it while I return the VST basket this Monday to the shop for a refund.

    Until I get this new basket (which I hope will fit snuggly) I'll default to the pressurised basket that came with the machine.

    Leave a comment:


  • Jackster
    replied
    I suggested getting a easier basket to work with than the vst. You can't sort anything out if it's channelling.

    My vst has had a dead spot right in the middle, even with a convex tamper. I wasn't getting enough grinds out around the edge of the basket, so the middle was packed more densely and not flowing as much. I think I have it sorted now...hard to see that without a naked portafilter.

    BCG refers to your grinder.

    It's a steep learning curve. At least you had the sour, and then the bitter. So you can pick the differences and taste the changes.

    Leave a comment:


  • Gil80
    replied
    What's BCG?

    At what point should I give up and return the machine?

    Leave a comment:


  • level3ninja
    replied
    Originally posted by Gil80 View Post
    Even though, it seems that there's too great variation between the sour and bitter tastes when adjusting grind settings by one.
    I would guess you are getting some serious channelling. VSTs are more prone to channelling and the BCGs clumping doesn't help that at all.

    Leave a comment:

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