Official Luthiers Forum!
http://mowrystrings.luthiersforum.com/forum/

Testing Hygrometers
http://mowrystrings.luthiersforum.com/forum/viewtopic.php?f=10101&t=50269		 Page 1 of 1
Author:  Dave Rickard [ Tue Feb 06, 2018 2:54 pm ]
Post subject:  Testing Hygrometers
I use potassium Bicarbonate in wine making so I have it on hand.
Rather than buy Potassium Carbonate can I use Potassium Bicarbonate to check a hygrometer?
Author:  Colin North [ Tue Feb 06, 2018 3:04 pm ]
Post subject:  Re: Testing Hygrometers
Potassium Carbonate is used commonly for checks because the RH of a saturated solution is 43 which is useful for us builder types, and doesn't vary a lot with temperature.
Good luck finding what the RH for a saturated solution of the bicarbonate, I googled it and had no luck.
P.S. Fortunately, Potassium carbonate is pretty cheap, try ebay?
Author:  Dave Rickard [ Tue Feb 06, 2018 3:11 pm ]
Post subject:  Re: Testing Hygrometers
Thanks Colin.Yep I tried googling it also with no luck.
I was relying on the wisdom of the group.
I may have to get a crow bar and pry my wallet open and buy the right stuff.
Author:  arie [ Tue Feb 06, 2018 3:14 pm ]
Post subject:  Re: Testing Hygrometers
a $5.99 calibration kit won't do?
Author:  bcombs510 [ Tue Feb 06, 2018 5:47 pm ]
Post subject:  Re: Testing Hygrometers
arie wrote:
a $5.99 calibration kit won't do?


FWIW, the two calibration kits I saw on Amazon test at 75% and 35%. I read somewhere (maybe here :)) that assuming that the reading is linear might be a mistake. Meaning, assuming that +1 at 75% would just be +1 at 45% is not guaranteed. So the potassium carbonate test which I think hits 43% is closer to the luthier Goldilocks zone.



Sent from my iPhone using Tapatalk
Author:  J De Rocher [ Tue Feb 06, 2018 6:26 pm ]
Post subject:  Re: Testing Hygrometers
https://www.amazon.com/dp/B00J5SWLK0/re ... 1_ST1_dp_1

This amount is good for years of tests.
Author:  Dave Rickard [ Tue Feb 06, 2018 10:19 pm ]
Post subject:  Re: Testing Hygrometers
Well now y'all now how cheap I am.
Author:  Hesh [ Tue Feb 06, 2018 10:58 pm ]
Post subject:  Re: Testing Hygrometers
Dave Rickard wrote:
Well now y'all now how cheap I am.


Bet I'm cheaper....

Three words:

Wet Bulb Testing

What Brad said about these various chemical tests have sweet spots for accuracy in terms of range where a Wet Bulb Test could care less. Two cheap lab thermometers and either a vac or fan and you're in business.
Author:  jfmckenna [ Tue Feb 06, 2018 11:18 pm ]
Post subject:  Re: Testing Hygrometers
You used to be able to get those Psychro-Dyne psycrometers for pretty cheap on eBay and they are perfect for calibrating cheap hygrometers.
Author:  Dave Rickard [ Wed Feb 07, 2018 6:48 am ]
Post subject:  Re: Testing Hygrometers
[quote="Hesh"
Bet I'm cheaper.....[/quote]

They call me "Nickel Dave"
When I pry my wallet open moths come flying out
I'd bet ya but I don't want to take the risk.

Thanks guys
Author:  arie [ Wed Feb 07, 2018 3:10 pm ]
Post subject:  Re: Testing Hygrometers
J De Rocher wrote:
https://www.amazon.com/dp/B00J5SWLK0/ref=pe_385040_30332190_TE_3p_M3T1_ST1_dp_1

This amount is good for years of tests.


"Loud Wolf" brand.. omfg -how loud is the wolf?
Author:  Bryan Bear [ Thu Feb 08, 2018 12:42 am ]
Post subject:  Re: Testing Hygrometers
I think I’m going to fill a big bucket with wet potassium carbonate in the shop and keep the door closed. Then I won’t need a hygrometer because the room will always be 43% :)
Author:  joe white [ Thu Feb 08, 2018 9:27 am ]
Post subject:  Re: Testing Hygrometers
Brilliant! [:Y:]
Author:  doncaparker [ Thu Feb 08, 2018 1:08 pm ]
Post subject:  Re: Testing Hygrometers
Bryan Bear wrote:
I think I’m going to fill a big bucket with wet potassium carbonate in the shop and keep the door closed. Then I won’t need a hygrometer because the room will always be 43% :)


Sploosh! My mind is officially blown. "No, man! We're IN the bag! Right now!"
Author:  bcombs510 [ Thu Feb 08, 2018 1:22 pm ]
Post subject:  Re: Testing Hygrometers
I was kind of surprised how much heat that little dish kicked out when I did this recently.


Sent from my iPhone using Tapatalk
Author:  Bob Shanklin [ Thu Feb 08, 2018 11:18 pm ]
Post subject:  Re: Testing Hygrometers
jfmckenna wrote:
You used to be able to get those Psychro-Dyne psycrometers for pretty cheap on eBay and they are perfect for calibrating cheap hygrometers.


They still are cheap on fleabay, and they are fantastic for calibrating.

Bob
Author:  Michael.N. [ Fri Feb 09, 2018 3:43 am ]
Post subject:  Re: Testing Hygrometers
bcombs510 wrote:
I was kind of surprised how much heat that little dish kicked out when I did this recently.


Sent from my iPhone using Tapatalk


With Potassium carbonate you get a reaction that produces heat. Shouldn't be enough to set the place on fire but not sure about a bucketful.
Author:  doncaparker [ Fri Feb 09, 2018 6:33 am ]
Post subject:  Re: Testing Hygrometers
I suppose the bucket of wet potassium carbonate doesn’t pass the “how will I explain this to the paramedics” test. Darn.
Author:  Bryan Bear [ Fri Feb 09, 2018 10:04 am ]
Post subject:  Re: Testing Hygrometers
I suppose I should say, for the record, I am not keeping an open bucket of potassium carbonate in my workshop. My typing tends to look the same whether my tongue is in my cheek or not. . .

I'm glad to hear that the reaction gives off heat though. It will give me a little more time before my hide glue gels. Wait, there I go again. . . :)
Author:  bcombs510 [ Fri Feb 09, 2018 10:13 am ]
Post subject:  Re: Testing Hygrometers
Porcelain dishes suspended from the ceiling approximately 3 feet above the work area. Should be able to get rid of any heat lamps you might be using.
Page 1 of 1 All times are UTC - 5 hours
Powered by phpBB® Forum Software © phpBB Group
http://www.phpbb.com/