Grown Tent Pieces Parts

Fascinating photos, airscapes!

It has been a week since getting the humidity under control.
There is a marked improvement of the Dwarf plants, leave are uncurling and looking much happier.  However do see some tip and edge yellow/burn on younger leaves.  I am still not sure if this is a nutrient level issue or caused by the change in humidity on Sundays when the tent is open or maintenance.   
Since the range of Humidity during the day is not the same for at night, have bumped the control form 68-70 this will keep things between 65 and 70% which falls in the range for both day and night if grown in a green house.  Different sites list different values but 70 seems to be in the range no matter which site you look at.
 
Still working on my follow the sun dimmer control, it is more a fun engineering project than of any value to the plants as far as I can tell.   This new accessory will have the dimmer on the lights at lowers setting %5 and slowly move it up to whatever value I have set (55% atm) over an hours time after power comes on in the morning.  Then around 1/2 through the day cycle will increase the lever by 10% for 2 hours and an hour before power goes off reduce back to 5% to sort of simulate the sun.   There are light available that do this and also actually alter the frequency of the light to match the day.  Those are a bit pricy .

The humidity controller looks awesome! I love the 3d printed enclosure, it looks neat and tidy.

It is interesting to me that it works so well with setting a hard cutoff humidity at 68%. In the commercial control systems I have seen before, they have a “buffer” range in which fans/windows are controlled so for example fans would turn on if humidity is over 69% and turn off once its below 67%. It prevents the fans from being switched on/off too rapidly. But maybe because the fans are small and tent is small it works just fine to have a hard cutoff, I suppose working the fans for shorter bursts might be better than having them work too hard to correct for a larger difference in humidity. Nice work!

The Sunrise > Sunset control is in first stages of production testing.  This control  will start the lights at 5% output, raising it to where I have it set via controller (60%ish) over 1 hour.  Then 5 hours later increases about 10% to 75ish%  over 1 hour of time, then back down to starting point over the next hour.  At the end of the day, 1 hour before power off, it drops back down  to 5% which is lowest output.

The setup is working as designed and programed.  However, I am not happy with the friction control of the dimmer potentiometers.  And the code is not as stream line as I would like. So my next objective is to convert the friction control to gears.  Before that I have to learn how to 3d model the gears I will use.. Once that is complete I will focus on the program rework.  Overall this has been a great engineering and programming project.  I did expect the friction drive to fail, it has not, but I fear it is putting undue lateral stress on the pots and I would rather not do that.  I still don't have any idea how to tell if the plants even care.. 
For those who may notice the red button, that is a by-pass button to jump out of the hour long climb from sunrise to normal should the power be interrupted in  mid day by myself or a power blip.   Otherwise "Never Push the Red Button!" 

airscapes, Do you recommend any particular 3D printer? I have a Dremel that can only use PLA filament. I'm not really looking to replace it, because I have so little time to use it, but I can dream ....