Author Topic: Improved Refractometer Correction calculator  (Read 18859 times)

Offline klickitat jim

  • I must live here
  • **********
  • Posts: 8604
Re: Improved Refractometer Correction calculator
« Reply #45 on: February 04, 2018, 11:02:31 PM »
You guys think dme will dissolve in room temp water? I might break out my stir plate for this project

Offline Robert

  • Official Poobah of No Life.
  • *
  • Posts: 4214
Re: Improved Refractometer Correction calculator
« Reply #46 on: February 04, 2018, 11:09:23 PM »
You guys think dme will dissolve in room temp water? I might break out my stir plate for this project
Jim, I liked this idea and I don't care about the super bowl hype I'll miss.  I just made up some samples with BOILING water and stuck them in the fridge to chill to room temp.  Never thought to try with cool water, but hot works.

If I do decide to use the old refracto again, I'll know my number! Thanks for the idea.
Rob Stein
Akron, Ohio

I'd rather have questions I can't answer than answers I can't question.

Offline klickitat jim

  • I must live here
  • **********
  • Posts: 8604
Re: Improved Refractometer Correction calculator
« Reply #47 on: February 04, 2018, 11:23:11 PM »
You betcha. I'll try dme in room temp on the stir plate and see what happens. Actually, i have a bunch of precanned 1.040 to start with. Record my findings, add more... etc etc. I don't think it needs to take 6 months of brew days to figure this out.

Something fun to do that should end up with easier results. Maybe even more reliable results, given that we're learning that hydrometer in suspended solids is inaccurate
« Last Edit: February 05, 2018, 12:17:33 AM by klickitat jim »

Offline klickitat jim

  • I must live here
  • **********
  • Posts: 8604
Re: Improved Refractometer Correction calculator
« Reply #48 on: February 05, 2018, 12:20:35 AM »
You guys think dme will dissolve in room temp water? I might break out my stir plate for this project

While I've never tried dissolving DME in cold water, this 
http://blog.brewingwithbriess.com/kiss-those-dme-clumps-goodbye-2/
suggests your approach will work.
Hilarious! Thanks

Offline Robert

  • Official Poobah of No Life.
  • *
  • Posts: 4214
Re: Improved Refractometer Correction calculator
« Reply #49 on: February 05, 2018, 12:20:43 AM »
You guys think dme will dissolve in room temp water? I might break out my stir plate for this project
Jim, I liked this idea and I don't care about the super bowl hype I'll miss.  I just made up some samples with BOILING water and stuck them in the fridge to chill to room temp.  Never thought to try with cool water, but hot works.

If I do decide to use the old refracto again, I'll know my number! Thanks for the idea.

Well, my samples (3) were all over the place, correction factor ranging from 0.93 to 0.98.  I'm just going to keep on not using the refractometer,  I don't trust it. Part of why I quit using it.  I'll rely on my longtime experience that tells me my mashing procedure is solid!  But hey, it was fun to give this a try.  Hope you have better luck, Jim, I know you kinda dig that refractometer!
Rob Stein
Akron, Ohio

I'd rather have questions I can't answer than answers I can't question.

Offline Robert

  • Official Poobah of No Life.
  • *
  • Posts: 4214
Re: Improved Refractometer Correction calculator
« Reply #50 on: February 05, 2018, 12:26:01 AM »
You guys think dme will dissolve in room temp water? I might break out my stir plate for this project

While I've never tried dissolving DME in cold water, this 
http://blog.brewingwithbriess.com/kiss-those-dme-clumps-goodbye-2/
suggests your approach will work.
Made my day! 😂
Rob Stein
Akron, Ohio

I'd rather have questions I can't answer than answers I can't question.

Offline klickitat jim

  • I must live here
  • **********
  • Posts: 8604
Re: Improved Refractometer Correction calculator
« Reply #51 on: February 05, 2018, 12:32:04 AM »
You guys think dme will dissolve in room temp water? I might break out my stir plate for this project

While I've never tried dissolving DME in cold water, this 
http://blog.brewingwithbriess.com/kiss-those-dme-clumps-goodbye-2/
suggests your approach will work.
Made my day!
Reinheitsgebort-bort-bort

Offline Robert

  • Official Poobah of No Life.
  • *
  • Posts: 4214
Re: Improved Refractometer Correction calculator
« Reply #52 on: February 05, 2018, 12:36:39 AM »
So I'm thinking. Long ago when I got my refractometer it was reliable.  Then at some point it seemed to become anything but (this little test confirms that's still the case) so I just stashed and forgot it. Wonder if anyone knows of them just going bad?  (It is a <$100 model.)
Rob Stein
Akron, Ohio

I'd rather have questions I can't answer than answers I can't question.

Offline klickitat jim

  • I must live here
  • **********
  • Posts: 8604
Re: Improved Refractometer Correction calculator
« Reply #53 on: February 05, 2018, 12:41:17 AM »
Seems to me the simple ones are totally mechanical, like a pair of binoculars. Maybe something got knocked loose. But my most likely suspect is that your solution was not totally homogenous. Big volume with hydrometer in it, measuring gravity of the whole volume... Then tiny variable sample on the refractometer.

Hence why I'll be doing mine on a stir plate. 10 min stir, measure, add , 10 min stir etc

Did you recalibrate before each sample?
« Last Edit: February 05, 2018, 12:47:06 AM by klickitat jim »

Offline Robert

  • Official Poobah of No Life.
  • *
  • Posts: 4214
Re: Improved Refractometer Correction calculator
« Reply #54 on: February 05, 2018, 12:53:51 AM »
Seems to me the simple ones are totally mechanical, like a pair of binoculars. Maybe something got knocked loose. But my most likely suspect is that your solution was not totally homogenous. Big volume with hydrometer in it, measuring gravity of the whole volume... Then tiny variable sample on the refractometer.
Either is possible.  It got farther off the higher the gravity, and mechanical misalignment could do that, or the lack of homogeneity would be more of a factor as gravity went up.  But I did try to avoid just that kind of problem with the samples, and if the cheapies are all mechanical,  I'll bet on jiggly bits inside the thing. Don't really need it, won't bother with it again. 

Good lesson for anybody thinking of buying one -- you get what you pay for!

 And hydrometers and iodine are dead simple.
Rob Stein
Akron, Ohio

I'd rather have questions I can't answer than answers I can't question.

Offline Big Monk

  • Brewmaster
  • *****
  • Posts: 840
  • I’m Derek Scott. Trappist Please! 🍷 🇧🇪
    • The Modern Brewhouse
Re: Improved Refractometer Correction calculator
« Reply #55 on: February 05, 2018, 12:54:14 AM »
So I'm thinking. Long ago when I got my refractometer it was reliable.  Then at some point it seemed to become anything but (this little test confirms that's still the case) so I just stashed and forgot it. Wonder if anyone knows of them just going bad?  (It is a <$100 model.)

Not sure but mine cost all of $15 and is bang on every time.
“It doesn't matter how beautiful your theory is, it doesn’t matter how smart you are. If it doesn't agree with experiment, it's wrong.“ Richard Feynman

"Messieurs, c’est les microbes qui auront le dernier mot." Louis Pasteur

www.themodernbrewhouse.com

Offline klickitat jim

  • I must live here
  • **********
  • Posts: 8604
Re: Improved Refractometer Correction calculator
« Reply #56 on: February 05, 2018, 12:57:59 AM »
Mine is Chinese cheaply too

Offline Robert

  • Official Poobah of No Life.
  • *
  • Posts: 4214
Re: Improved Refractometer Correction calculator
« Reply #57 on: February 05, 2018, 01:06:59 AM »
Mine may have been ok at some point then, but it did definitely start wildly disagreeing with my hydrometer all of a sudden years ago. If I ever replace it I guess I won't worry about price, though I've heard  cheap ones derided by those with $3000 or whatever bench models.  Of course they have to rationalize their investment!
Rob Stein
Akron, Ohio

I'd rather have questions I can't answer than answers I can't question.

Offline tommymorris

  • I spend way too much time on the AHA forum
  • ********
  • Posts: 2700
Re: Improved Refractometer Correction calculator
« Reply #58 on: February 05, 2018, 01:37:52 AM »
After reading the post above, it's confirmed my decision to stick with a hydrometer.
I applaud you for actually reading it.

Offline tommymorris

  • I spend way too much time on the AHA forum
  • ********
  • Posts: 2700
Re: Improved Refractometer Correction calculator
« Reply #59 on: February 05, 2018, 01:44:17 AM »
FWIW, I love my hydrometer and use it for OG and FG. I generally don’t know how accurate it is. Ball park is close enough for me.

I did check it against my hydrometer today. The Refractometer + BeerSmith calculator matched a hydrometer for the FG of a batch of blonde ale.