Flow rate of a rotary pump espresso machine - Page 5

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erics
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#41: Post by erics »

See this:

Group jet for an Elektra A3 .

I have some left over from the GS3 project - ~0.60 mm
Skål,

Eric S.
http://users.rcn.com/erics/
E-mail: erics at rcn dot com

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cafeIKE
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#42: Post by cafeIKE »

nixter wrote:9bar on the button. I'll measure longer tonight.
9 bar where? On puck flow post gicleur or the tuppeny gauge w blind basket?

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HB
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#43: Post by HB »

Grant wrote:So....where can I find a "real" gicleur for the Elektra with this flow rate? (....not that I see any reason why my copper wire restrictor will not work for some time.)
According to Dave, a Keihin motorcycle carburetor jet will fit. See Group jet for an Elektra A3 for discussion and related topics Low flow from a 1993 Elektra T1 and Elektra T1 - trouble with channeling / early blonding.
Dan Kehn

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nixter

#44: Post by nixter »

erics wrote:And your pump pressure is?

You would be much better off measuring the flow in 30 seconds or 60 seconds and dividing appropriately.
Over 30 sec the volume was 400ml or 133ml/10sec
cafeIKE wrote:9 bar where? On puck flow post gicleur or the tuppeny gauge w blind basket?
Read from the gauge on the machine.. unrestricted@8.5bar, blind basket@9.25bar.

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nixter

#45: Post by nixter »

So let's say I want to reduce my flow rate down from the current 133ml/10sec. I've read that installing a smaller gicleur will effectively reduce the pressure at the group even though the on board pressure gauge won't reflect this. If this is true then why not just reduce the pump pressure to reduce the flow rate? Or will that not have an effect on flow rate? Assuming adjusting the pump pressure won't reduce flow rate then a)How do I access my gicleur? b)How do I measure such a small hole to figure out what size I have? c)Where do i find different sized gicleurs?

Thanks,
n

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erics
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#46: Post by erics »

Adjusting the pump pressure will reduce the flowrate but not significantly within the ranges espresso machines are accustomed to. Flow is proportional to the square root of the pressure.
How do I access my gicleur? b)How do I measure such a small hole to figure out what size I have? c)Where do i find different sized gicleurs?
You read the links that others have referred to in this thread :) .
Skål,

Eric S.
http://users.rcn.com/erics/
E-mail: erics at rcn dot com

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nixter

#47: Post by nixter »

Eric, I can't believe you're making me work on a Sunday. :D

Ok so I know how to get to the gicleur. Standard e61 gicleurs appear to be different than Elektra gicleurs though so the Keihin jets are out. I can find a single .5mm e61 gicleur on espressoparts.com. (fun searching when "gicleur" is spelled 3 ways, 2 on EP alone!) I'm still not sure how to measure the one in my Evo. I have an email in to Rocket so perhaps I can find out without having to disassemble anything.

Is there anything special I need to know about removing the top cap? As in.. "be careful of X" or whatever.

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nixter

#48: Post by nixter »

So the Evo has a .8mm gicleur and a 3mm thermosyphon restrictor. Seeing as the .5mm e61 gicleur is only one I can readily find online I may order that and give it a go.

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SiD-

#49: Post by SiD- »


I simply put a ball valve to the output of the rotary pump to regulate the flow rate.
First I set the ideal flow rate with the valve, then I set the maximum water pressure on the bypass valve of the pump. I think it is a good solution for a one group, home use machine.
The machine is an Olympia Express Maximatic. Now with external rotary pump. :roll:

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erics
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#50: Post by erics »

Where did you get that info from? Possibly the parts book the dealer graciously copied for you? :)

The usual gicleur installed in E-61 machines is 0.70 mm; the usual gicleur installed in Elektra's is 0.80 mm; the usual gicleur installed in the LM GS3 is 0.60 mm. Actual gicleur sizing can vary +/- 0.05 from advertised from what I have seen but all of this is just an FYI.

Thermosyphon restrictors, when utilized, are typically 2.0 to 3.0 mm .

I would at least put a little faith in the mfg (Rocket) that they knew what they were doing and would concentrate on getting to know the machine and your grinder and your coffee choices. This does not occur overnight - GUARANTEED.
Skål,

Eric S.
http://users.rcn.com/erics/
E-mail: erics at rcn dot com