Our Valued Sponsor
OpinionsConsumer ReviewsGuides and How TosCoffeeGeek ReviewsResourcesForums
Coffee: Machines and Brewing Methods
Strange problem with weighing water for V60
Green Unroasted Coffee
Free shipping. Save 15% on variety pack, use 'variety' at checkout
www.madbeanscoffee
 
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 > Coffee > Machines > Strange problem...  
view previous topic | view next topic | view all topics
showing page 2 of 2 first page previous page
Author Messages
jpender
Senior Member
jpender
Joined: 11 Jul 2011
Posts: 708
Location: California
Expertise: I like coffee

Grinder: OE LIDO
Vac Pot: S/S Moka Pot
Drip: Aeropress
Posted Thu Jan 31, 2013, 11:56am
Subject: Re: Strange problem with weighing water for V60
 

Nice to see you got to the bottom of it.

There must be a thermal carafe that would suit your needs. Even a glass one would be better than metal. In the meantime why not just use a hot pad, a piece of ensolite, or a copy of Everything But Espresso?

Unfortunately the spec sheets for inexpensive scales tend to lack details. Temperature sensitivity is usually given in ppm/C and for a cheap scale would be in the tens of ppm, not enough to cause you a problem. But that's within operating temperature limits. Setting a metal container of really hot water on the metal weighing pan almost certainly pushes it outside of these (unstated) limits. I tried this last night with my cheapo scale (American Weigh SM-501). I poured boiling water into an aluminum bottle, sealed it and placed it directly on the metal pan. After about 5 minutes of this mistreatment the scale drifted 0.5%, not enough to have been noticible during a pourover. Either your scale is more sensitive to mistreatment or your carafe got it a lot hotter than my aluminum bottle got my scale.

edit: From the CJ-4000 manual:

"Avoid lengthy exposure to extreme heat or cold, your scale works best when operated at normal room temperature."

"Do not operate near an in-use cell phone, cordless phone, radio, computer or other electronic device. These devices emit RF and can cause unstable scale readings."
back to top
 View Profile Link to this post
dyqik
Senior Member


Joined: 7 Oct 2011
Posts: 383
Location: Cambridge, MA
Expertise: I love coffee

Espresso: Bezzera BZ07 PM
Grinder: Baratza Virtuoso Preciso...
Vac Pot: Cona D
Drip: Bona-Vita, CCD, Aeropress.
Roaster: Gene Cafe, Modded Poppers
Posted Thu Jan 31, 2013, 12:23pm
Subject: Re: Strange problem with weighing water for V60
 

The temperature sensitivity quoted will be measured with the scale at the same temperature throughout - it'll be an environmental temperature.  With a hot coffee carafe on top, you're heating one part more than the others, and the sensitivity could be much higher.

A cork mat or similar would probably be good enough insulation for the duration of a V60 pour.
back to top
 View Profile Link to this post
jpender
Senior Member
jpender
Joined: 11 Jul 2011
Posts: 708
Location: California
Expertise: I like coffee

Grinder: OE LIDO
Vac Pot: S/S Moka Pot
Drip: Aeropress
Posted Thu Jan 31, 2013, 4:52pm
Subject: Re: Strange problem with weighing water for V60
 

dyqik Said:

The temperature sensitivity quoted will be measured with the scale at the same temperature throughout - it'll be an environmental temperature.  With a hot coffee carafe on top, you're heating one part more than the others, and the sensitivity could be much higher.

Posted January 31, 2013 link

That may be true as well. The point I was making was that the sensitivity drift (had it been specified for the Jennings) would only be valid over a limited temperature range.
back to top
 View Profile Link to this post
andys
Senior Member
andys
Joined: 10 May 2003
Posts: 857
Location: NY
Expertise: Just starting

Espresso: Speedster, Londinium 1
Grinder: EK-43,Robur, HG One, M3
Vac Pot: Yama
Drip: various
Roaster: PIDed Popper
Posted Fri Feb 1, 2013, 4:45am
Subject: Re: Strange problem with weighing water for V60
 

DoctorBeans Said:

I tried it today with a book underneath the carafe and I saw no drift in the weight measurement

Posted January 31, 2013 link

This could lead to great thread about which books work best. For instance, I've gotten poor results insulating with books published by Random House -- my readings were all over the place.

 
-AndyS
picture page:  http://flickr.com/photos/andy_s/sets/
back to top
 View Profile Visit website Link to this post
Buckley
Senior Member


Joined: 25 Jan 2011
Posts: 423
Location: Internet
Expertise: I love coffee

Posted Fri Feb 1, 2013, 7:24am
Subject: Re: Strange problem with weighing water for V60
 

I do the same thing with a preheated mug right on the metal of my CJ-4000 and have never had the spurious readings that you are reporting.  I am glad insulation solved your problem.  Perhaps they reengineered more recent models (mine is about 10 months old).  I will look out for the same.  Thank you for your post and I am glad someone knew the solution.
B
back to top
 View Profile Link to this post
yakster
Senior Member
yakster
Joined: 25 Feb 2009
Posts: 1,043
Location: San Jose, CA
Expertise: I live coffee

Espresso: Gaggia Factory / La Peppina...
Grinder: Vario / Kyocera
Vac Pot: Yama 8 + Pyrex Lox-in Rod
Drip: Brazen / Kalita / Chemex /...
Roaster: Behmor
Posted Fri Feb 1, 2013, 11:35pm
Subject: Re: Strange problem with weighing water for V60
 

I'd heard of this in various places but it really came to light for me when Able Brewing ran into it with the Elite Scale 1000.  They ended up pulling the product back and liquidating their inventory from what I can glean from Twitter.

I picked up four cork coasters for a buck or two to use on the scale at home and work.

 
-Chris

LMWDP # 272
back to top
 View Profile Visit website Link to this post
showing page 2 of 2 first page previous page
view previous topic | view next topic | view all topics
Discussions > Coffee > Machines > Strange problem...  
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.
Great Espresso at Home
Curated selection of the best machines from La Spaziale, Izzo, Quick Mill, La Marzocco & more.
www.clivecoffee.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. (0.274466991425)
Privacy Policy | Copyright Info | Terms and Conditions | CoffeeGeek Advertisers | RSS | Find us on Google+