Jar sized Hygrometer/Thermometer

Nah looks great just knock those burrs off and it will lay more flush :)

Did you glue it in yet

yea, i missed a few burrs in my rapid cleanup.

did not glue it in yet. can't be airtight, but it is a tight fit.

i'll check it later to see if the humidity is holding
 
yea, i missed a few burrs in my rapid cleanup.

did not glue it in yet. can't be airtight, but it is a tight fit.

i'll check it later to see if the humidity is holding

I just made a jar lid with mini meter like yours. Took me all of 5 minutes with my Dremel tool. The fit was tight enough that it should be air tight, but I might glue it in just to make sure. Thanks for the great suggestion. P.S. I put a packet of 55% in the empty jar and will see how close it comes to that. With my mini meter, it can take up to 3 hours to come to a final reading.
 
I just made a jar lid with mini meter like yours. Took me all of 5 minutes with my Dremel tool. The fit was tight enough that it should be air tight, but I might glue it in just to make sure. Thanks for the great suggestion.

awesome, but the credit for the idea really belongs to @charface

agree, i have not glued mine and humidity is holding fine. will watch it over the next few days.

already ordered some more meters :bigjoint:
 
I just made a jar lid with mini meter like yours. Took me all of 5 minutes with my Dremel tool. The fit was tight enough that it should be air tight, but I might glue it in just to make sure. Thanks for the great suggestion. P.S. I put a packet of 55% in the empty jar and will see how close it comes to that. With my mini meter, it can take up to 3 hours to come to a final reading.

plastic lid?
 
I wish it were my idea, others here and im sure elsewhere have already done it.
So thank you, whoever you are. Lol
 
Walmart has 6 packs of plastic mason jar lids (with threads) in store for $2.45. I have 3 China bought mini hygrometers that cost me only $5.10 free shipping for all 3. They all compared within 1% of my Accurite hygrometer. Took 5 weeks to arrive from China tho. These only read Celcius, which is no big deal. They have a slight flange which makes it fit nicley on the top of the cutout lid. I'm evaluating how accurate it is. I have a pack of Boost 55% inside the jar, and so far the top meter reads 45% while the inside mini reader already reads 48%. So, I'm still in the evaluation process. I'll give it overnight. It might end up being the meter inside reads more accurately than the meter stuck into the lid.
 

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Stay tuned. This method of inexpensive mini hygrometers inserted into the lid of a mason jar to read jar humidity may not be accurate. My mini hygrometer reading inside an empty jar of a fresh Integra 55% packet is getting closer to 55% humidity (48% now), while the lid hygrometer is behind in coming up on humidity reading (45%). I'm suggesting that micro type hygrometers may only read accurately when they're placed inside the jar. The fit is airtight.

Heh. Just to make sure , I placed some Saran wrap over the jar and a rubber band to see if that changes things.
 
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Or they are just not calibrated in sync?

Would be hard to believe cheap meters are all calibratex the same but i could be very wrong
Hmmm
Now im getting the wheels turning
 
My gauges were a bit off.
I calibrated against my digital then wrote +2 for on the face of the one that was off by two.

Ill have to test like you did once they are together and hopefully if they are off I can just update my calibration mark
 
Or they are just not calibrated in sync?


These are hygrometers that cost $1.10 ea. Free shipping.
(All 3 read well within reason in my tent, when next to my more expensive Accurite hygrometer nearby).

Who knows? So far, all these dollar hygrometers are still suspect to me. China makes millions of them. All 3 read within reason of each other (in my grow tent along side a more accurate hygrometer), but not so much now with the meter in lid thing. Still evaluating.
 
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