ToeSmack's Build Diary


Hey all,

This build log is going to be mostly pictures and situations I’ve run into that are specific to my build. It’s going to be a log of what NOT to do, I hope it saves you all a lot of headaches :slight_smile: .

So first off, do not use this “other” kind of punched angle from Home Depot. You’ll spend most of your day cutting and grinding to get it to fit. While I did finally get it all to match up, it was a serious pain in the ass.

Lesson: Make sure you get the punched angle with ONLY 3/8 holes.

My box is off on one side, I believe this is because the foam panel was bowed a bit. I cut it on a table saw to exact measurements but I think the inconsistencies of it being bowed are showing. I’m not sure what to do here yet since I’ve already taped it all up. I may just re-do it later but I’m progressing to the motherboard section for now.

Lesson: Don’t build the foam box until you’re done with the frame. This will allow you to test fit each section of glue-up.


Very usefull. Thank you Derek


I totally agree with your “Lesson”. I built the shell before I had the parts of the frame. I have quite a gap at the bottom which I am filling in with extra weatherstripping.


Same here. Although I did build the frame first. Got like 4mm gap at the top and left… Lets see if it maters. If it does… New shell :slight_smile:
I think I welded the frame just tiny bit off…


I’ll take comfort in the fact I’m not alone in my screw-up, I’m sure it won’t be the last :slight_smile:


Things are progressing nicely on my build. My small little space has been completely overtaken :slight_smile:


At last! An update!

Sorry everyone for the long delay in updates to my build but I’m happy to report that I’m ready to grow!

Using the Arduino output to test the sensors on the bench before pairing it back up to the chassis.

Evian water bottles were the only bottles I could find to fit the humidifier.

Lesson: Don’t cross 12v like I did. I got lucky in that it didn’t fry any sensors or controllers, just wires, you might not be as lucky. This happened because I was testing the LED strip lights using alligator clips, they touched and the blue smoke was let out. Edit: It’s worth noting that in this picture I had the wire wrapped on the two GND pins (bottom left) instead of 51/52 so don’t use this picture as a reference.

ISSUE 1: One thing I had to troubleshoot were the AC relays. When they were activated, the LED would illuminate on the board, but the relay didn’t actually “click”. I needed to tap them with something for them to activate. I thought the relay block may have been bad at first, but then I switched the ground wire to use the DC power supply ground instead of from the grove connector that was ultimately connected to the Arduino. Success! With the new ground, all the relays worked fine.

ISSUE 2: My light sensor wasn’t reporting any information, and would “lock up” the Arduino when it was connected to the I2C connector. Upon further inspection I ordered an analog light sensor instead of a digital light sensor.

Once I worked out these small issues I wanted to see how high I could get the humidity in the chamber. I guessed it would max out around ~80%, I was wrong. It took about 1.5 hours to reach this level, ambient humidity in my garage was around 20%.

My grow kit is mostly assembled. Right now I’m waiting on the calcium nitrate and rockwool cubes.

That’s it for this update! Hopefully the next one will include plants!


The first grow is underway. I’m going to run this recipe until they start to sprout and after that I’ll add light and lower humidity.

Here are the references I used to start the germination process.

Chamber set-points

CO2 = 1250ppm
Temperature = 20c
Rel. Humidity = 95%
Lights off

Germination Process

  1. Soak Rockwool cubes in pH 6.0 water.
  2. Inject 2 seeds per cube (I’ll need to pluck out duplicates after they sprout).


2.5 days later and I have my first sprouts. Lowered humidity to 60% and wrote a recipe for 16 hour on, 2 hour off light cycle. My garage is pretty warm since it’s ~85-90 degrees in the daytime. The vent is pretty much always running but there’s not much I can do about that. Even with it running the temperature and humidity are still within acceptable limits for lettuce.


Day 7.

5 on the left is butter head lettuce, 5 on the right is romaine. The romaine did not germinate which isn’t surprising since I didn’t even look into what it required, it was more of test. There is only 10 spots available on the foam float anyway. I’ve got a few observations.

  1. I planted two seeds in each pod and I’ve got 100% germination.
  2. The plants have not sprouted uniformly, the ones on the far left seem to be doing better than the ones in the middle. I’m not really sure why, maybe temperature/humidity differential closer to the air exit vent?
  3. I tested the pH of the water that I’ve been using to water and it was too high, at around 7. I made the mistake of not testing the pH AFTER I soaked the Rockwool cubes, research shows that the cubes will raise the pH so make sure you test it again after you soak. (I’ve adjusted it since, back down to 6)
  4. Because it’s been so hot during the day here, it has been difficult to get the temperature low enough and the humidity high enough since the vent is constantly trying to vent the warm air. I’ve cracked the window at the top and it has helped.

I plan on transplanting to the hydro setup when leaves are overlapping, and all of the plants have roots poking out the bottom. It should happen around day 11.


Day 10.

Transplanted into the tub.

I chose to use small net cups instead of just putting the rockwool cubes into cut holes. Nutrient solution is Jacks 3-2-1 method.

3 grams Jacks 5-12-26 / per gallon
2 grams Jacks Calcium Nitrate / per gallon
1 gram of magnesium sulfate. / per gallon

I combined them in this order: 5-12-26, magnesium sulfate, cal nitrate.
~910 ppm
pH balanced to 6 making sure to dilute the pH down first and not adding it directly to the solution.

I’m not even using the EC/pH meters that the build called for. If the sensors can’t be submerged 100% of the time, they’re more a hassle than anything so I just use a good combo meter to test it periodically.


Day 14


Day 15


Wow, there is clearly a marked improvement. This is great, well done:slight_smile:


Day 25


Day 30, harvest day.