Our Valued Sponsor
OpinionsConsumer ReviewsGuides and How TosCoffeeGeek ReviewsResourcesForums
Espresso: Espresso Machines
pressure profiling with vibe pump
Stefano's Espresso Care
Repair - Parts - Sales
Factory Authorized &
Trained Technician
www.espressocare.com
 
Not Logged in: Log In to Postlog in
New Topics updated topics   New Posts new posts   Unanswered Posts new unanswered  
Search Discussion Board search   Discussion Board FAQ faq   Signup sign up  
Discussions > Espresso > Machines > pressure...  
view previous topic | view next topic | view all topics
showing page 1 of 10 last page next page
Author Messages
AndyPanda
Senior Member
AndyPanda
Joined: 12 Jul 2010
Posts: 769
Location: San Francisco Bay Area
Expertise: I love coffee

Espresso: Olympia Cremina, Various...
Grinder: Mazzer Major, Fiorenzato,...
Vac Pot: vintage Corey
Drip: AeroPress
Roaster: BreadMachine/HeatGun
Posted Sat May 12, 2012, 2:46pm
Subject: pressure profiling with vibe pump
 

When I first got started with espresso, I read a lot about pre-infusion and thought a lot about ways to mod my machine to that.  For a couple of years I ran my Gaggia Classic with a couple of resistors in-line with the vibe pump and wired to a three way toggle switch.  This allowed me, by switching one or both resistors in/out of the circuit, to let the pump go full blast or medium or low.

For the longest time I would simply run a really slow flow/low pressure for 6-10 seconds to preinfuse and then go full pressure.

Then I went with a different mod that gave me full variable pump pressure rather than just the three settings.  But still I was always thinking of it as low pressure preinfuse and then full pressure for the rest of the shot.  And for most espresso blends this seemed to work really well.

Now just today I came across this review:
Click Here (www.home-barista.com)

Now I do have some roasts that just haven't worked well as espresso ... and after reading that review and watching the video it was nothing short of a revelation to me - the idea of controlling the shot pressure to adjust how long you are in the chocolate/caramel phase.

I just tried pulling some shots of my troublesome roast using my variable pressure setup to try and duplicate the way Jim pulled his Esmeralda Geisha in the video link posted above.  

I started the shot letting it build to full pressure long enough to fully saturate the puck (droplets just starting to appear at bottom of basket) and then dropped the pressure and as the shot began to pour, continued adjusting the pressure (keeping it pretty low) throughout the shot to keep the trickle extremely slow.  I was able to bring out the chocolate and caramel of this coffee and pull a really great ristretto - the result was fantastic.  

This particular coffee and roast works well as brew but as espresso has never worked at all (bright/grapefruit peel/too acidic - sink shot) ... using the variable pump control to start out full pressure and then back off to 2 bars or so for a few seconds and then just dial the pump gradually through the rest of the shot (I'm guessing between 4-6 bars most of the time after the initial 9 bars) to keep the shot barely trickling and very dark in color I was able to get a really interesting and great shot with a vibe pump machine.
back to top
 View Profile Link to this post
AndyPanda
Senior Member
AndyPanda
Joined: 12 Jul 2010
Posts: 769
Location: San Francisco Bay Area
Expertise: I love coffee

Espresso: Olympia Cremina, Various...
Grinder: Mazzer Major, Fiorenzato,...
Vac Pot: vintage Corey
Drip: AeroPress
Roaster: BreadMachine/HeatGun
Posted Sat May 12, 2012, 6:17pm
Subject: Re: pressure profiling with vibe pump
 

Here's a video of the Gaggia showing the variable pressure control of the pump.  Sorry for the poor quality video taken with my phone.
http://www.youtube.com/watch?v=joQs13t15QI
back to top
 View Profile Link to this post
GlennV
Senior Member


Joined: 27 Oct 2011
Posts: 29
Location: UK
Expertise: I love coffee

Posted Tue May 15, 2012, 11:00am
Subject: Re: pressure profiling with vibe pump
 

This is interesting, how did you do the pump control? I tried this and had good results with both resistors and phase control for the pre-infusion part of the shot - but neither was able to maintain a low flow into a highish pressure without the pump stalling. I came to the conclusion that current limiting would be the answer but never pursued it and went instead for a hydraulic solution with needle valves, as Slayer do it. As for your conclusions though, yes I agree - it can make an enormous difference with harder to extract coffees.
back to top
 View Profile Link to this post
epengr
Senior Member
epengr
Joined: 1 Apr 2012
Posts: 46
Location: Saskatoon
Expertise: Just starting

Espresso: NS Oscar
Grinder: Baratza Vario
Posted Tue May 15, 2012, 5:21pm
Subject: Re: pressure profiling with vibe pump
 

+1 for how did you do the pump control?!

It seems to me that if this works it would be a much easier way to tweak the pressure to the brew group down to ~9.0 bar for for machine that don't have an OPV (as opposed to plumbing in an OPV...)  Or if the control not fine enough to achieve this?

Thanks in advance!
back to top
 View Profile Link to this post
germantownrob
Senior Member
germantownrob
Joined: 2 Dec 2007
Posts: 2,140
Location: Philadelphia
Expertise: I love coffee

Espresso: Duetto 3, A Dead Oscar
Grinder: Vario-W, Preciso w/Esatto,...
Drip: Brazen
Roaster: Diedrich IR-1, HT B
Posted Tue May 15, 2012, 5:54pm
Subject: Re: pressure profiling with vibe pump
 

Click Here (www.home-barista.com)

Click Here (www.home-barista.com)

Just some reading until Andy responds.
back to top
 View Profile Link to this post
Frost
Senior Member
Frost
Joined: 26 Jul 2007
Posts: 2,070
Location: Sierra
Expertise: I love coffee

Espresso: Isomac Venus
Grinder: Lelit PL53
Roaster: Poppery I w/variac, MET, BT
Posted Tue May 15, 2012, 6:58pm
Subject: Re: pressure profiling with vibe pump
 

"Is anyone using voltage to control Vibe pump pressure instead of OPV?"

You can certainly control brew pressures in the range of 6-10 bar with a variable voltage device, dimmer, rheostat or variac, etc. Good control in the range of 75 to 110 volts should be good for this pressure range.
back to top
 View Profile Link to this post
SJM
Senior Member


Joined: 17 Nov 2004
Posts: 1,707
Location: CA
Expertise: I love coffee

Espresso: SAMA, Gaggia Classic
Grinder: K-10PB, Rancilio MD-50
Vac Pot: no like
Drip: no like
Roaster: HotTop
Posted Tue May 15, 2012, 7:06pm
Subject: Re: pressure profiling with vibe pump
 

What I wonder is whether buying a Variac (or other device mentioned above) and putting whatever sort of drag onto the pump might not cost more in the long run (in worn out pumps??) than the cost of installing an adjustable OPV?
back to top
 View Profile Link to this post
wsikes
Senior Member
wsikes
Joined: 3 Oct 2011
Posts: 396
Location: West Virginia
Expertise: I love coffee

Espresso: Gaggia Classic
Grinder: Promac MD-64 AT
Drip: Bunn
Roaster: Behmor
Posted Tue May 15, 2012, 7:33pm
Subject: Re: pressure profiling with vibe pump
 

SJM Said:

What I wonder is whether buying a Variac (or other device mentioned above) and putting whatever sort of drag onto the pump might not cost more in the long run (in worn out pumps??) than the cost of installing an adjustable OPV?

Posted May 15, 2012 link

I have heard this argument before, but haven't heard of anyone losing a pump while using this method.  I plan on installing a lamp dimmer on my Saeco Aroma this weekend... we'll see.
A thought on using a Variac... the vibrator pumps in espresso machines is usually in the 40-50 watt range.  Using a lamp dimmer rated at 300w makes the adjustments very sensitive (or so I hear).  I wonder if a Variac isn't rated at too high a voltage to make it practical.  I thought if using a router controller but have not tried it for this very reason.  Maybe I'll give it a look in a few days.  There are lamp dimmers out there rated at 100w and these would probably give nice control, but they are fairly scarce.  The 300w lamp dimmers are prevalent with a scattering of 200w dimmers around.
There is another thread running concurrently with this one and there are some good links and information in it.  You might want to check it out.

"Modifying Saeco Via Venezia (OPV, p. gauge, depres. PF, pressure profiling, etc)"

Also, here is a link showing the installation of a lamp dimmer in a Saeco/Starbucks machine.

Click Here (www.saecomods.com)

 
Bill
back to top
 View Profile Link to this post
Frost
Senior Member
Frost
Joined: 26 Jul 2007
Posts: 2,070
Location: Sierra
Expertise: I love coffee

Espresso: Isomac Venus
Grinder: Lelit PL53
Roaster: Poppery I w/variac, MET, BT
Posted Tue May 15, 2012, 9:28pm
Subject: Re: pressure profiling with vibe pump
 

The wattage rating on those devices is a maximum rating to avoid burning them up. There is no problem in using them for a lower wattage device. The issue of getting good resolution to control pump pressure is another matter however.  You will need an easy smooth response in the 75-110Volt range.

I wouldn't worry about pump damage when driving it at lower voltages. It certainly won't burn it up and so the next problem is the pump might stall. No harm done there....
back to top
 View Profile Link to this post
AndyPanda
Senior Member
AndyPanda
Joined: 12 Jul 2010
Posts: 769
Location: San Francisco Bay Area
Expertise: I love coffee

Espresso: Olympia Cremina, Various...
Grinder: Mazzer Major, Fiorenzato,...
Vac Pot: vintage Corey
Drip: AeroPress
Roaster: BreadMachine/HeatGun
Posted Wed May 16, 2012, 7:34am
Subject: Re: pressure profiling with vibe pump
 

I used to do it with resistors and a switch to bypass them.  But the way I'm doing it now is with a rotary lamp dimmer.  I've read many posts worrying about these and suggesting they wouldn't work well or might be bad for the pump -- but, at least with the dimmer I used, it works perfectly.  

I still get flow at the very slowest setting even though you can barely hear the pump (very quiet).  And the pressure is variable from about 1 bar to 9 bars (where the OPV is currently set).  And it is very smooth (even though in the video my gauge is jumping all around - I think I had air in there).

I have been getting the best espresso I've ever had - very different from what I was getting before.  And it has really widened the range of coffees I can use for espresso.  I'm now doing some lighter roasts that would be way too bright if pulled at 9 bars.  When I start out at 9 (just bring it up to 9 bars long enough to get the pour started) and then back down to 4-5 bars to keep the pour barely trickling, I get much more creaminess and rich deeper tones in the cup and much less of the citrus peel.  

It's just really cool to be able to vary the pressure to bring out different tones from the same coffee.  I've done some comparison shots with the same coffee, same grind, same dose - but one pull with straight 9 bar shot and then with the pressure profile I described above and the difference is dramatic.

The dimmer I used was $5.99 and the entire swing of the rotary dial is useful ... at no point (until you twist it to the "click" where it turns off completely) does the pump stop flowing - it just gets very quiet, low flow and low pressure.

My pump is the Invensys pump ... but I'll try doing the same on an Ulka and let you know how that works ... I expect it will give the same results.
back to top
 View Profile Link to this post
showing page 1 of 10 last page next page
view previous topic | view next topic | view all topics
Discussions > Espresso > Machines > pressure...  
New Topics updated topics   New Posts new posts   Unanswered Posts new unanswered     Search Discussion Board search   Discussion Board FAQ faq   Signup sign up  
Not Logged in: Log In to Postlog in
Discussions Quick Jump:
Symbols: New Posts= New Posts since your last visit      No New Posts= No New Posts since last visit     Go to most recent post= Newest post
Forum Rules:
No profanity, illegal acts or personal attacks will be tolerated in these discussion boards.
No commercial posting of any nature will be tolerated; only private sales by private individuals, in the "Buy and Sell" forum.
No SEO style postings will be tolerated. SEO related posts will result in immediate ban from CoffeeGeek.
No cross posting allowed - do not post your topic to more than one forum, nor repost a topic to the same forum.
Who Can Read The Forum? Anyone can read posts in these discussion boards.
Who Can Post New Topics? Any registered CoffeeGeek member can post new topics.
Who Can Post Replies? Any registered CoffeeGeek member can post replies.
Can Photos be posted? Anyone can post photos in their new topics or replies.
Who can change or delete posts? Any CoffeeGeek member can edit their own posts. Only moderators can delete posts.
Probationary Period: If you are a new signup for CoffeeGeek, you cannot promote, endorse, criticise or otherwise post an unsolicited endorsement for any company, product or service in your first five postings.
Home Espresso Machines
Watch videos with Gail & Kat, Rocket, Jura Capresso, Saeco, Rancilio, Quick Mill, Nespresso
www.seattlecoffeegear.com
Home | Opinions | Consumer Reviews | Guides & How Tos | CoffeeGeek Reviews | Resources | Forums | Contact Us
CoffeeGeek.com, CoffeeGeek, and Coffee Geek, along with all associated content & images are copyright ©2000-2014 by Mark Prince, all rights reserved, unless otherwise indicated. Content, code, and images may not be reused without permission. Usage of this website signifies agreement with our Terms and Conditions. (0.397921085358)
Privacy Policy | Copyright Info | Terms and Conditions | CoffeeGeek Advertisers | RSS | Find us on Google+