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bongo
05-02-15, 04:19
This week's experiment is with pre-infusion time.

I.e., on my DB vib pump (from reservoir), I lift the lever until the valve opens, you see the pressure drop and hear the water flow, then raise the lever fully to extract and pour...

But for how long? tick, tock....:clock:

DoubleShot
05-02-15, 04:23
I've been trying 5 secs on my Brewtus DB. Wholelattelove mentioned in one of their YouTube videos not to over do it. 10+ secs is probably too long. 5 to 7 secs should be about right.

jeebsy
05-02-15, 04:28
I don't think ti really works like that from a tank....try lifting the lever just past halfway and see if you get a constant flow

DoubleShot
05-02-15, 04:31
By flow do you mean reading on the dial?

jeebsy
05-02-15, 04:35
No, if water comes out the group. Do it without the PF in

DoubleShot
05-02-15, 04:37
Oh, I do that before extracting my first shot once the machine has fully warmed up. Thought pre-fusion meant adding very minute amount of water to grounds for a short while prior to lifting lever all the way up then more water being forced through group head?

I guess you're suggesting I try what you mentioned to see if pre-infusion actually works on my tank fed vibration pump?

jeebsy
05-02-15, 04:46
E61 does preinfuse a bit, but i'm not sure if there's any benefit to holding the lever in the middle position for an extended amount of time on a tank fed machine. Try lifting the lever just past halfway and see if you get a bit of water or a steady, slow flow.

DoubleShot
05-02-15, 04:48
Yeah I wasn't expecting similar results to say a L1 or GS3 but thought I'd give it a whirl. What's the worst that could happen...it doesn't make much difference, lol!

bongo
05-02-15, 04:58
I don't think ti really works like that from a tank....try lifting the lever just past halfway and see if you get a constant flow

It works.... see vid I just made...Nothing arrives for about 2 seconds, then a good flow with little pressure.


http://youtu.be/jat6_AVADHg

jeebsy
05-02-15, 05:00
Did the flow increase when the pump kicked in?

DoubleShot
05-02-15, 05:00
Brilliant! I do like clicking on links and videos that get posted on threads that interest me! [emoji4][emoji106]

bongo
05-02-15, 05:01
Did the flow increase when the pump kicked in?

Yes.

I could have run the video longer, but yes it did increase.

DoubleShot
05-02-15, 05:03
So what have we learned here? That pre-infusion does work on a tank fed Brewtus DB?

bongo
05-02-15, 05:05
As we say here in Somerset (and sometimes more associated with Gloucestershire)...

"YARP"

bongo
05-02-15, 05:06
Now back to the original question.... How long do people do this for?

Eyedee
05-02-15, 05:36
Isn't the concept of pre-infusion to build up the liquid pressure slowly so that the surface of the grinds are pre wetted before the pressure begins to build.

Having looked at the manual for my Brewtus I don't see a way of altering the pre-infusion time.

Ian

DoubleShot
05-02-15, 05:38
It's for however long you have the lever lifted to between 1/3 and half way up (just before you feel a click) I believe.

Eyedee
05-02-15, 05:41
The idea is that the machine does all this for you, I don't think it's supposed to be a manual process, lift the lever, pre-infusion begins then the pressure begins to build.

There was a discussion on this previously. http://coffeeforums.co.uk/showthread.php?6016-Espresso-pre-infusion

Ian

bongo
05-02-15, 05:54
while the machine does/can do this automatically due to the 'filling chamber' (that's my words not necessarily official), the process is pump driven and quite quick. There is a video explaining this mechanism online.

By lifting the lever as I do in the video, the pump does not kick in but water flows, wetting the grounds. From this point you have options;

1) push the lever down to close the valve. This will allow the water to saturate the coffee. Then lift the lever and off you go.

2) push the level up to start the pump and continue to extract as per normal.

3) vary the time that the lever is in the mid position which will ultimately effect the saturation (*assumption) before lifting the lever fully.

So there are a plethora of options.

Don't do it and use the 'automatic' preinfusion.
Vary the volume of water using the 'lever in mid position' option.
Vary the time of saturation before starting normal extraction.

Personally, I haven't played enough to notice a difference (yet).

Why am I asking - well I am interested, but mainly because I'm avoiding doing work.

DoubleShot
05-02-15, 06:04
What I tried whilst making three flat whites this morning was lifting lever to just before mid position, you can hear it make a sound and the needle on dial fluctuates a little, hold in this position for approx. 5 seconds then lift lever all the way up and begin extraction. Turned out better than yesterday's efforts. Whether that's down to me getting closer with dialling in the beans or due to this attempt at pre-infusion...I can't answer 100%. Still learning...

jeebsy
05-02-15, 06:25
Mrboots pre infuses for....get ready it..... 18 SECONDS

DoubleShot
05-02-15, 06:30
His machine though...worlds apart?!

jeebsy
05-02-15, 06:32
Try it out. I always go for 5-6 seconds but don't really have a basis for why. Garydyke uses 10 on his sage i think

The Systemic Kid
05-02-15, 06:47
Using 10-12 secs at the moment - grinding super fine.

Mrboots2u
05-02-15, 07:02
Mrboots pre infuses for....get ready it..... 18 SECONDS

My pre infusion is at 2 bar or slightly less
The brewtus i dont think can replicate this in tank form.

jeebsy
05-02-15, 07:05
My pre infusion is at 2 bar or slightly less
The brewtus i dont think can replicate this in tank form.

Don't know what pressure the tanked delivers, was curious about that earlier

I use two bar for pre infusion, got a regulator on the line pressure

bongo
05-02-15, 07:17
Don't know what pressure the tanked delivers, was curious about that earlier

If you look at the trickle it certainly isnt 2 bar!

Just for clarity's sake, please could responses regarding preinfusion times be kept to those using the Brewtus?

Looking at the pressure, I think thatafter 4-5 seconds little more would be achieved, so may as well open her up, unless you simply want to give extra time to soak into and between the grounds...

jeebsy
05-02-15, 07:30
You'd be surprised how feeble ny two bar trickle is

Mrboots2u
05-02-15, 08:12
Reading this may be useful...
http://www.home-barista.com/espresso-machines/is-there-purpose-for-e61-middle-brew-lever-position-t3643.html

bongo
05-02-15, 08:36
Reading this may be useful...
http://www.home-barista.com/espresso-machines/is-there-purpose-for-e61-middle-brew-lever-position-t3643.html

I enjoyed that read. Basically, sod playing with pre-infusion until everything else is sorted, as it will only just highlight your poor methodology / technique...

Back to hitting the lever 'ON' for me then! haha

jeebsy
05-02-15, 10:58
If you look at the trickle it certainly isnt 2 bar!


http://www.youtube.com/watch?v=NpK_p3dKxTk

unoll
07-02-15, 12:04
Sorry of I'm treading old ground but........ Do you seasoned brewtus users start timing the shot for 25-30secs once the brew head reaches 9 bar or just start the timer once I push up the lever?

DoubleShot
07-02-15, 02:14
I start once I've lifted the lever up fully. If that's wrong then I guess I'm not seasoned 'yet!' [emoji16]

jeebsy
07-02-15, 10:02
Soon as water hits the puck (so when lever goes past the middle click)

twotone
07-02-15, 04:48
Funnily enough I've been playing about with the pre-infusion last night and this morning after watching a video that someone posted (thanks) and either I'm getting better a pulling a shot or the pre-infusion really works as the espresso has undoubtedly been better since.

I pre-infuse for about three seconds.

Tony

DoubleShot
07-02-15, 04:51
Now where's bongo got to?! [emoji12]

simonp
08-02-15, 06:21
E61 does preinfuse a bit, but i'm not sure if there's any benefit to holding the lever in the middle position for an extended amount of time on a tank fed machine. Try lifting the lever just past halfway and see if you get a bit of water or a steady, slow flow.
I didn't think it would make a difference but i tried it a few months back and it does seem to help reduce donut extractions. Could just be coincidence of course [emoji4]

bongo
10-02-15, 10:18
I've been busy playing with my [insert funny text].....

PRE-INFUSION times of course...!!!

I've not been up to much TBH as I've been grinder-less since selling on my Jolly, and my Zenith is in transit somewhere between Italy and the UK.

Curiously, I went to Colonna and Smalls and got some beans ground but unfortunately the Brewtus choked on it HARD. I think I got down to 7g before a drip came through and that was without tamping!

I then tried it I'm my Europicola but was pressing so hard I was forcing the gasket open between the head and the body!

Ended up binning the lot....

The C&S machine must be a Gold's Gym member the amount of bar its pushing....

DoubleShot
10-02-15, 10:42
The C&S machine must be a Gold's Gym member the amount of bar its pushing....

Too funny! [emoji16]

Mrboots2u
16-02-15, 12:36
https://www.youtube.com/watch?v=2jn28YTS3OQ#action=share
If you havent seen this already , it may make clearer how the e61 on your brewtus is working ...

dfk41
16-02-15, 01:03
I have been thinking this through, and am probably wrong of course, but I do not see how an E61 can really pre-infuse in the truest sense. If you mean pre-infuse, by definition ofttimes differential between starting the shot and first drops then is that pre infusion? On a lever, you lower the arm, count for an amount of time, and the way I do things, only once I have lifted the lever back do drips or flow start, which is my understanding of pre infusion. Once you lift the lever, then the spring takes over the pressure of the shot, so the pre-infusion meaning water being forced into the puck is doing just that, wetting the puck. On a pump machine, once you press the shot, so the machine is pumping x bar through the puck which is not the same.....or is it?

bongo
16-02-15, 03:22
Once you lift the lever, then the spring takes over the pressure of the shot, so the pre-infusion meaning water being forced into the puck is doing just that, wetting the puck. On a pump machine, once you press the shot, so the machine is pumping x bar through the puck which is not the same.....or is it?

I'm confused by your question / procrastination . I take it you're not talking about the brewtus but a lever machine? If so I have no idea how the good ones work - it also makes the thread slightly confusing due to being a totally different machine. (Less I just simply haven't understood of course).

With respect to the expobar/brewtus, I thought the video helped explain things quite well. I.e., what ever pressure is in the boiler tank pushes water through, which on the HX machine he is talking about is 0-9bar - this would obviously be a small volume of water at most, due to the constraints of space of the boiler's size and rapid drop in pressure as the water left. Then, only when the lever is lifted fully is the water pumped through.

What It could mean, if the brewtus worked exactly the same way, is that you may not be able to control the volume of water or pressure the water is pushed through at for the 'pre-infusion' before the pump is activated. (I feel another investigation coming on).

Unfortunately I'm not aware if this is exactly the same for the brewtus as its not a HX machine, so the pressures could vary, but as for how the e61 head works it was very clear.

Study design:
How about all of us get the machine up to temp. Then, recording the output, lift the lever to open the valve and weigh the output. We could correlate the output against time.
then, we could repeat this but using a pressure gauge on the portafilter to check the pressure that builds as the water flows through.

At the end we may be able to assume that if the lever is lifted for 'x' number of seconds then 'y' volume of water will pre-infuse the puck at an average pressure of 'z'.

Please add comments if anyone thinks this is worth while, suggesting any needed changes they can think of....

Mrboots2u
16-02-15, 04:51
https://www.youtube.com/watch?v=HWpOVdryALk#action=share

Rob666
16-02-15, 05:19
This may shed a little light:
http://youtu.be/zKDvJUxrXDo

dfk41
16-02-15, 05:39
Perfusion takes place with a reduced pressure. Can this be achieved on a Brewtus? DO you have any 'control' over the pressure once the pump kicks in?

Mrboots2u
16-02-15, 07:19
Perfusion takes place with a reduced pressure. Can this be achieved on a Brewtus? DO you have any 'control' over the pressure once the pump kicks in?
Have you watched the clip i posted.....

jeebsy
16-02-15, 07:28
Perfusion takes place with a reduced pressure. Can this be achieved on a Brewtus? DO you have any 'control' over the pressure once the pump kicks in?

Mine is plumbed so i get line pressure, this is reduced through a valve to two bar. Once the pump kicks in you're at pump pressure though

DoubleShot
16-02-15, 07:39
I've been manually pre-infusing for around 5 secs with my Brewtus IV as shown in wholelattelove video above. Don't ask me if it's made a noticeable difference to taste in the cup because I've been adjusting and experimenting other factors with some Swiss Espresso beans for the past fortnight.

DoubleShot
16-02-15, 07:40
Have you watched the clip i posted.....

I just watched both videos. [emoji4]

bongo
02-03-15, 11:30
out of curiosity, has anyone got a portafilter with pressure gauge they could put onto the Expobar to see what pressure actually does build up on a tank fed machine with the lever set to the 'magic' position...? (make sure there is water in the tank of course :p)

If so, please do get a video of it and also show the temperature at the time.

Thanks in advance...

DoubleShot
02-03-15, 11:39
Don't have a pressure gauge but do have an EricS thermometer fitted to the group head which measures the temperature of water passing through the group head. By 'magic' position do you mean just above the neutral position and therefore in pre-infusion mode?

bongo
03-03-15, 08:33
yes.... the place where the 'magic' begins haha

Obnic
03-03-15, 10:16
I preinfuse to just before the point where beads of coffee appear through my PF basket. Takes a little experimentation to get the time right for a given grind.

The Brewtus isn't the most flexible of tools but I have, in the past, 'primed' the group head by lifting the lever all the way up to put a little pressure into the group (the E61 preinfusion chamber softens the impact on the puck) then clicking the lever back to the mid position to allow that pressure to diffuse into the puck, before lifting the lever once more to extract.

With the Brewtus, I think the main benefit was elimination of donuts and a more even extraction. With a machine that has proper low pressure pre-infusion the benefit I perceive is that you can grind quite a lot finer which definitely changes taste.

DoubleShot
03-03-15, 02:55
I dedicate these two videos to bongo. First clip is in the 'magic' position. The second is with the lever turned fully upwards.

https://vimeo.com/121137100

https://vimeo.com/121137162

Now you just need someone with a pf pressure gauge to post a video and Bob's ya Uncle! [emoji4]

DoubleShot
03-03-15, 10:36
Forgot to mention display reading on EricS thermometer is supposedly 1.25 degrees C higher than the actual temperature of water exiting the group head.

bongo
03-03-15, 10:42
Like that!

out of curiosity what was the temperature set to on the machines display? Just wondering how it compares to the temperature at the head...

DoubleShot
03-03-15, 10:57
94 degrees c.

bongo
04-03-15, 07:29
So it actually runs hotter then.. As didnt your temp guage read out at 96 and rising?. I thought it would be cooler not hotter