Edit: Better link 
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Neat! Gotta love graphs and data.
Can you elaborate a bit more on your process or methodology?
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I’m tinkering with a new drybox system. I had two old 2x4 tents lying around and got to thinking, what if I turned them sideways and stacked them, so I had a lower and upper area.
The lower box houses a 20" box fan, and an ultrasonic mist maker in a bouncer pitcher of RO water.
Between the lower and upper chambers is a cardboard sheet with 100’s of holes drilled through it, like an air hockey table.
On top of that cardboard I’ve placed two 16x20x1 carbon impregnated MERV 11 furnace filters, side by side. MERV 11 is enough to catch mold spores.
On top of that is a 60" closet rack. And not shown, I place stackable stainless steel drying racks across the rack, it fits 4 neatly, and can stack up 6x high if needed.
An inkbird humidity controller is looking for 62.6% RH, with a sensor placed 2" above the rack.
When it senses a low humidity condition (under 61.6% or -1% delta), it powers up the box fan and the mister. When it senses a high humidity condition (over 63.6%, or +1% delta) it powers up that exhaust fan to suck air out of the top chamber.
The data you see is for three samples in that dry tent. I weigh them over and over on a gram scale. The chart is % weight compared to fresh/live. The “fun” is in the trendline… that’s a 2nd order polynomial fitting SO well, that it can predict when I jar down to the hour.
It also shows evaporation “velocity” and “acceleration” which help to visualize things and adjust. Acceleration for example would help best to show if one side of the tent is buffering against swings better. In the case here, I see that the 907 side is a bit more finicky.
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Version 2
Air goes into the lower “box” via slits on each side, then mixed with fans, and pulled through two furnace filters measuring 25" x 16" each.
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We’re looking for <0.80 kPa VPD (so realistically shooting for 0.7X) derived from our drybox temp and humidity. We will go lower in the future on v3, when we add cooling.
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We’re targeting a not-to-exceed VPD by controlling humidity and allowing whatever ambient temps are experienced. Fortunately it’s winter. In this case we’re hovering around 63-64 F or 17.5 C. We’re going with an average of 63.5% RH, low 0.7X kPa.
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Zero odor permitted, caveat being that an open door will let some music out.
- Reliable, low input. Zero input is possible, maybe v3. I need to fill the humidifier res every 12 hours by hand. We might run a line from the RO system over to the res and trust a cheap 1/4 float valve?
- Jalalagod by Bodhi, flipped at day 30, harvested at day 70 of 12/12. Will update next when finished.
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Fantastic! Love the implementation and how you are dialing it in 
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Clearly you are a wizard sir. Thanks for the share. I like the ingenuity.
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UPDATE
The latest drydown experiment has concluded. Jalalagod went 7.5 days from harvest, losing 75% of it’s harvest weight, at an average of ~0.70 kPa VPD, now holding 65% in sealed jars.
A 3rd order poly fit this curve, shown. A second order did not. On my end I’ll continue to compile these curves over time to see what’s what.
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UPDATE
The latest (3rd) drydown experiment has concluded. TKNL5 Haze F3 (Haze Dominant) by AKBB went 9 days from harvest, losing 77% of its harvest weight, at an average of ~0.71 kPa VPD, now holding 66% in sealed jars.
I botched a macro and wasn’t recording the actual temp (red boxed data) at each point so the VPD calcs are off a bit, if anything they are calculated higher than actual (conservatively high VPD).
- I’ll take the next experiment to 10 days clean and see how the weight loss goes.
- TKNL5 was a bit less dense than Jalalagod, but interestingly it dried more slowly given the ~same VPD target.
- TKNL5 is fantastic, btw.
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