A funny thing happened on the way to the forum today . The great christmas eve crash of 2006. Silver lining - I got to re-register and put the "y" in my screen name that I forgot the first time.
Anyway, I will relist this thread.
The discussion centered around setting up a programmed dose for the V2. Turns out while some have been able to set a dose using plain water and an empty PF and getting the same pour with a packed PF, others - me and Stubaby - have not had consistent volumes with or without this this method which led us to think that we are either doing something wrong or maybe there is an issue with the flow meter on some machines.
I am rewriting this for the benefit of others who may have this issue and also because when I call Chris' I will post follow up.
What is my aim with Volumteric dosing?
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Niko
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chas
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Re: What is my aim with Volumteric dosing?
I'm not sure if you've added new information this time or if I am just reading it differently. Are you saying that if, for example, you set the dosing to exactly 2oz without coffee in the PF and then pull successive shots still w/o coffee in the PF, you get widely varying amounts each time and not approx. 2 oz each time??? If so, that doesn't sound right. I can see that with coffee the amount can vary with coffee, roast, grind, age, phase of the moon, etc. but without coffee in the PF, I would expect pretty consistent results.italyhound wrote:
Turns out while some have been able to set a dose using plain water and an empty PF and getting the same pour with a packed PF, others - me and Stubaby - have not had consistent volumes with or without this this method which led us to think that we are either doing something wrong or maybe there is an issue with the flow meter on some machines.
That said, I've never seen an accuracy spec on the volumetric doser's flow sensor.
Chas
LM GS/3 & LaSpaziale Dream v 1.25 (US 120V)
Mazzer Kony E, Customized Rocky
Hottop P/B
LM GS/3 & LaSpaziale Dream v 1.25 (US 120V)
Mazzer Kony E, Customized Rocky
Hottop P/B
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italyhound
This is what Stubaby and I have been experiencing. Chris' said you must set dose with coffee (even though others here say it's not necessary) but Stubaby was getting volumes all over the place with and without coffee. I remembered getting various amounts as well but checking tonight again with an empty PF I was getting consistently 2.25 oz pours. Now I remember setting it at about 1 oz or so with coffee and can check accuracy tomorrow but I also would not expect that of the 2.25 oz dispensed that it would all end up in the cup - I assume that's a correct assumption since water would also end up in the puck right?
I will check a few runs tomorrow with a full PF but Stubaby did and got varying volumes. Maybe he will repost.
I will check a few runs tomorrow with a full PF but Stubaby did and got varying volumes. Maybe he will repost.
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Weska
If you guys haven't seen this thread http://www.home-barista.com/forums/viewtopic.php?t=2402 at Home-Barista, then you might be interested in AndyS's idea of describing our drinks to each other by the ratio of dry bean weight to weighed coffee throughput in the cup.
The application here is that, if you have a 0.1 gram scale, you could check on your doser's consistency through coffee better by weighing than by volume. Presumably, the doser is stopping after a certain volume of water has passed through it. That volume should depend on the temperature of the water in the line, presumably pretty stable in our Vivaldis, and the accuracy of the doser. If dose, distribution and tamp are all consistent--and the beans are all of one kind--the throughput weight should reflect the doser's performance.
By the way, I do find a major difference in the throughput when I set the doser with and without coffee in the portafilter. Seems to me that it should be set with a loaded portafilter.
The application here is that, if you have a 0.1 gram scale, you could check on your doser's consistency through coffee better by weighing than by volume. Presumably, the doser is stopping after a certain volume of water has passed through it. That volume should depend on the temperature of the water in the line, presumably pretty stable in our Vivaldis, and the accuracy of the doser. If dose, distribution and tamp are all consistent--and the beans are all of one kind--the throughput weight should reflect the doser's performance.
By the way, I do find a major difference in the throughput when I set the doser with and without coffee in the portafilter. Seems to me that it should be set with a loaded portafilter.
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StuBaby
I spoke to Roger at Chris'. He and I beleave that the impeller in the flow meter may spin too fast without coffee in the PF, the high rpm being out of accurate range for reproducible dispensing. With coffee in the PF, flow is slow enough such that the rpm signal to the PC board is within accurate range and thus reproducible volume dispensing is possible.
I spoke to Jason at Chris' today who thinks the large variance in dispensing volumes with coffee in the PF is too large in my case to be explained by grind amount, finesse, and tamp alone. I told him I plan to keep a better record of grind weight and tamp pressure once my boiler's heat sensor is replaced. He said that if necessary, they can send me out another "flow meter brain" is necessary (what ever that is).
I spoke to Jason at Chris' today who thinks the large variance in dispensing volumes with coffee in the PF is too large in my case to be explained by grind amount, finesse, and tamp alone. I told him I plan to keep a better record of grind weight and tamp pressure once my boiler's heat sensor is replaced. He said that if necessary, they can send me out another "flow meter brain" is necessary (what ever that is).
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Niko
Did you guys get your VII's with the volumetric doser already set to dispense single and doubles shots?
I'm just wondering about this because my old S1 arrived without it being set, the double shot button would dispense forever and the single didn't pour anything out (it just clicked).
But my VII arrived setup already, just glad I didn't have to do it. It was a nice surprise to push the buttons and get the exact shot quantity.
I'm just wondering about this because my old S1 arrived without it being set, the double shot button would dispense forever and the single didn't pour anything out (it just clicked).
But my VII arrived setup already, just glad I didn't have to do it. It was a nice surprise to push the buttons and get the exact shot quantity.
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maxspivak
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Niko
Sounds about right, try it with some old coffee (so you don't waste fresh) to measure how many oz's you're getting. For a single shot you should be getting about 1.25 oz - 1.75 (@the most), the latter would be an ideal setting to dose most coffees with some room to manually cut of for long extractions (if needed). I have my dosing set @ 1.4 oz which which works really well for me.
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maxspivak
Thanks Niko, but now I'm really confused...Niko wrote:Sounds about right, try it with some old coffee (so you don't waste fresh) to measure how many oz's you're getting. For a single shot you should be getting about 1.25 oz - 1.75 (@the most), the latter would be an ideal setting to dose most coffees with some room to manually cut of for long extractions (if needed). I have my dosing set @ 1.4 oz which which works really well for me.
I thought a single is 0.6 to 1 oz and a double is 1.2 to 2 oz espresso. That's where my problems are -- my doubles are closer to 3.5 extracted, which seems like too much.
http://www.home-barista.com/espresso-guide-skills.html
http://www.coffeeresearch.org/espresso/definitions.htm
I know this is not a specific LaSpaz question, but I figured I'll ask anyway, and will hopefully not blunder into inappropriate area too much.
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Niko
I know it's very confusing! Especially when a source says one thing and then another one says otherwise.
http://www.coffeekid.com/espresso/minifaq#whatis
It really depends how much coffee you're dosing your baskets with.
Do you weigh your beans? If you don't, you should get a little gram scale which will make a huge difference in your dosing consistency. You don't have to do what everyone else is doing, pulling exactly "so many" oz's of coffee into your cup - just find a sweet spot that works for you and go with it.
Follow your tastebuds, they don't lie.
Here's a quote from another source (Karen Siegelman):
"Generally speaking, a single shot of espresso is about 1 to 1.5 ounces, while a double shot measures 2 to 2.5 ounces".
-The Ristretto or the
http://www.coffeekid.com/espresso/minifaq#whatis
It really depends how much coffee you're dosing your baskets with.
Do you weigh your beans? If you don't, you should get a little gram scale which will make a huge difference in your dosing consistency. You don't have to do what everyone else is doing, pulling exactly "so many" oz's of coffee into your cup - just find a sweet spot that works for you and go with it.
Follow your tastebuds, they don't lie.
Here's a quote from another source (Karen Siegelman):
"Generally speaking, a single shot of espresso is about 1 to 1.5 ounces, while a double shot measures 2 to 2.5 ounces".
-The Ristretto or the