Hygrometer calibration to 65% with Bovedas

Bob_Luken

Is there any scientific reason, or ANY reason why we must wet some salt or use a calibration kit in order to calibrate specifically to a 75% RH reading? Why can't we make our own "65% calibration kits" (or whatever RH% boveda you happen to have) using a regular 60 gram Boveda in a small Tupperware container or Ziploc bag? I know some hygrometers have a simple reset button that conveniently resets to 75% but most of mine don't.  I have googled the crap out of this and so far I can't find any other reason why calibrating to 75% would be a necessity, but sometimes you guys can come up with genius level knowledge. Gimme that if you got any. Or make jokes. I like jokes. 

  And another thing,  if we are always advising the newbies to skip all the difficult humidification options and go straight to the easy bovedas, then why do we keep expecting them to master the salt test, which can be easily be screwed up by someones interpretation of "damp"? 

ForMud

My guess would be......Before Bovedas/Beads were around, the only true way to  know how far off your hygrometer was the salt test ( Known to be 75% ) 
I don't see any reason not to use any rh Bovedas to set them. 

peter4jc

I never liked the salt test - it can be accurate, and I guess anything that gives you an idea is good - but there are some variables involved that can make it not true.

Based on the calibration kit that Boveda sells, I'd say you can take any Boveda and use it to calibrate.

Bob_Luken

Disclaimer: I did not search all the threads within our forum to see if this has been discussed before, or even if I may have asked this question before. There are just too many threads on calibration/salt test etc. 

Bob_Luken

Let's word the question a little differently.

"Does calibrating to 65%RH result in hygrometer reliability equal to calibrating to 75%RH? If it does not, then why not?",...... (Besides the convenience factor of some hygrometers having a reset to 75%)

Bob_Luken

peter4jc said:

I never liked the salt test - it can be accurate, and I guess anything that gives you an idea is good - but there are some variables involved that can make it not true.

Based on the calibration kit that Boveda sells, I'd say you can take any Boveda and use it to calibrate.

 If you look at enough youtube how-to videos on the salt test you get a range of salt to water ratios from "damp" to "slushy" and that seems like it would produce a range of different results. 

Yakster

Agreeing with you Bob.  For best accuracy, you want to calibrate your hygrometer with a reference that is close to the readings that you expect, so in most cases I'm thinking 65% would be closer to most people's target range than 75%.

What I don't know is if Boveda's 75% calibration packs are somehow more accurate than their regular 65% packs.

If you have the Bluestream or Boveda branded Smart Sensor (formerly known as the Boveda Butler) you have to use the 75% calibration kit (which is included with the sensor) to calibrate it and you can optionally do a two step calibration with the 75% kit for 24 hours followed by a 32% calibration kit for 24 hours for more accuracy.

genareddog

What’s a salt test?

90+_Irishman

You mix a capful of salt and distilled water together so it’s damp/kinda wet and then put it and hygrometer in a bag. That puts the rH at 75% and you can calibrate your hygrometer based on that

Bob_Luken

What's a hydrometer? 

90+_Irishman

Huh?

Guitarded

Bob_Luken said:

What's a hydrometer? 

An inexpensive tool that makes @nal retentive people insane. 

jlmarta

A hydrometer measures the specific gravity of a liquid. 

A hygrometer mearures relative humidity. 

Class duemissed..... 

ForMud

Which brings another question to mind.....If I understand correctly, rh % is relative to temp.....So you would also need your test to be at what ever temp your humidor will be at to get the most accurate result.

cbuck

I’m going to just smoke my cigars! No wonder you guys only have one or two a week! Too much thinking!

Patrickbrick

I do not have a working hygrometer in my house and never have issues with a cigar (user error/rolling issues aside).  I use bovedas, when they start to harden up I recharge, those things really take the stupid out of the game.  I laugh when people post that their RH should be at 70% but it is at 67% followed by this is bad what do I do.  As for actually answering Bob's question I'm guessing it wont make much of a difference either way.  This sounds experimentation time for someone other than me.

Bob_Luken

cbuck said:

I’m going to just smoke my cigars! No wonder you guys only have one or two a week! Too much thinking!

Which guys are only smokin' one or two a week? Point 'em out! They gotta step it up. 

Bob_Luken

90+_Irishman said:

Huh?

I didn't mean to imply that you or anybody in this thread spelled hygrometer wrong. I just thought since you did such a good job explaining the salt test that I'd give you a shot at also educating everyone on hydrometers vs hygrometers. It was funny when I thought of it anyway. 

IndustMech

@Bob_Luken funny and educational

genareddog

Bob_Luken said:

90+_Irishman said:

Huh?

I didn't mean to imply that you or anybody in this thread spelled hygrometer wrong. I just thought since you did such a good job explaining the salt test that I'd give you a shot at also educating everyone on hydrometers vs hygrometers. It was funny when I thought of it anyway. 

I am sorry. I was being somewhat of a smartass when I asked what a salt test was. I will go hide under my rock again.

peter4jc

You have your own rock, Larry? Very cool! 

90+_Irishman

Bob_Luken said:

90+_Irishman said:

Huh?

I didn't mean to imply that you or anybody in this thread spelled hygrometer wrong. I just thought since you did such a good job explaining the salt test that I'd give you a shot at also educating everyone on hydrometers vs hygrometers. It was funny when I thought of it anyway. 

Lol ahh I gotcha and no worries. I honestly didn’t know and enjoyed hearing the answer from Marty and learned something myself. 

90+_Irishman

genareddog said:

Bob_Luken said:

90+_Irishman said:

Huh?

I didn't mean to imply that you or anybody in this thread spelled hygrometer wrong. I just thought since you did such a good job explaining the salt test that I'd give you a shot at also educating everyone on hydrometers vs hygrometers. It was funny when I thought of it anyway. 

I am sorry. I was being somewhat of a smartass when I asked what a salt test was. I will go hide under my rock again.

And I again show I have trouble understanding sarcasm haha. Sorry Larry didn’t know you were being funny and I was apparently the straight man lol

Yakster

I think Bob's referring to the traditional salt test employed at herfs... the host shakes salt on all newbies to make sure that they're not slugs.

genareddog

peter4jc said:

You have your own rock, Larry? Very cool! 

I have 2, one to hide under and one to hit you right between the eyes next time I see you 

BKDog

In theory, you can calibrate at any %RH, that's what calibration is for, to accurately adjust your hygrometer to a known level so it works at any point. It's just a long standing fact to use the salt method because NACL will hold humidity specifically at 75% RH, so that's what makes it a good tool to use.

If, let's say for example, my old tennis shoe holds humidity at a steady 15% RH (again this is only speculation), you would still achieve the same results when you set your hygrometer at that level and locked it in because it would then keep on doing what it normally does, which is deliver the relative humidity level to you. Therefore, if you use a Bovida of any %RH sealed in a bag with your hygrometer for a few hours, then set your hygrometer to that specific level, it ought to be pretty close to the results you get with salt. The only stipulation would be if you used an older Bovida pack or one which may not be quite as good as a brand new one, you could hypothetically be a little off.

Personally, all the digital hygrometers I've used have been within 2% to 3%, so that's good enough for my needs. The old school analog hygrometers are junk (in my honest opinion).