Hornet's DIY 250 Watt Insulated Attic Cab

[Headless Hornet]

Hello. This is the first of hopefully many posts documenting my first attempt at personal-use growing.

Goals:

Provide enough for my occasional use. No more, No less.

Do it simply, do it small, do it stealthy, do it cheaply, but most of all, do it right.

A few disclaimers right up front. I'm not under 18, I don't live with my parents, I'm not on probation, and I'm not a fucking idiot. I don't recommend growing to anyone, but especially not if you are unfortunate enough to be under any of the above circumstances.

That said, I am a complete newbie. I have no experience, I haven't read any books, I haven't asked anyone anything about growing. I haven't even posted questions on any forums.

What I have done is research. It is amazing how much you can learn with just Google and the Search button on the forums.

I will either crash and burn, or succeed and burn .

Construction details next.

[smookin]

Originally Posted by Headless Hornet

Hello. This is the first of hopefully many posts documenting my first attempt at personal-use growing.

Goals:

Provide enough for my occasional use. No more, No less.

Do it simply, do it small, do it stealthy, do it cheaply, but most of all, do it right.

A few disclaimers right up front. I'm not under 18, I don't live my my parents, I'm not on probation, and I'm not a fucking idiot. I don't recommend growing to anyone, but especially not if you are unfortunate enough to be under any of the above circumstances.

That said, I am a complete newbie. I have no experience, I haven't read any books, I haven't asked anyone anything about growing. I haven't even posted questions on any forums.

What I have done is research. It is amazing how much you can learn with just Google and the Search button on the forums.

I will either crash and burn, or succeed and burn .

Construction details next.

I'm already interested and pulling up a chair. Good luck to you and I can't wait to see how your first harvest turns out.

[GigZ-16]

Good luck. You'll gain experiance fast. Just be carefull with watering and fertilizing. Their the two biggest Newbie Mistakes. That and lighting.

[up4anything]

Good luck bro. Keep us posted.

[Headless Hornet]

Placement
I have several places within my home where I could have made a growbox/closet, but I eventually chose the attic. This area has the least chance of accidental discovery, but it is still easily accessible.

Attic advantages:
It's out of the way. Even the nosiest of houseguest doesn't snoop around in your attic. There is easy access to outside venting, electrical boxes, and even a drain for flushing. The living area stays isolated from odors, light leaks, noise, etc. The attic provides natural camo for the box. Wood, insulation, electrical wires, and ductwork look right at home in an attic. Throw in some old boxes, some stored-away Christmas decorations, etc, and nothing looks awry.

Attic disadvantages:
Temperature. My attic temps range from about 10 - 130 degrees F. Just in the last two weeks, I have recorded temps from 32 to 95 degrees F. During these intense swings, the inside temp of the growbox has stayed between 68 and 80 degrees F. Insulation and ventilation are the key.

Size
For the sake of simplicity, cost, and stealthiness, I purposely limited myself to a relatively small size. I wanted an area that could be well lit with a 250 Watt HPS and hold two or three plants. Again for simplicity, there is no separate mother/clone areas. I will be growing from seeds for awhile "Just big enough, Just big enough.." was my mantra during planning...

I have a reason behind every decision I made. That doesn't mean I made the right decisions though. Remember, I'm a N00B.

Where's the KEEF?

[Headless Hornet]

1. Cabinet Construction - Insulating Stress Panels composed of 1.5" Polystyrene insulation board surrounded by a frame of 1.5" x 1.5" Fir. Everything skinned on both sides with 1/4" luan plywood. Strong, relatively light, very well insulated. Panels are joined to one another with 3" wood screws. Panels can be disassembled easily.
Interior dimensions - 31" Wide x 17" Deep x 45" Tall

2. Ventilation - Active Exhaust to outside. 6" rigid ducting with 424 CFM inline fan on diy speed control rheostat. Passive intake using 6" flexible insulated ducting. All air brought in from a heated and air-conditioned room, thus box is effectively heated and air-conditioned also.

3. Main Lighting - 250 Watt HPS with remote ballast (outside of box) 250W Metal Halide conversion bulb used for veg.

4. Side lighting - 40 Watt total 24" T12 fixture. This probably does very little, I can place it in/under canopy, also provides different spectrum than main light.

5. Moveable Hood/Divider. - Effectively separates bulb heat from plant area. Bulb shielded from plants by double strength glass.

6. Air circulation - 9" oscillating fan (may have to eventually be moved to underneath canopy as plants grow toward max height)

7. Temp/Humidity Meter

8. Vegetative Pots - approximately 1.5 gallons. Cut down from paint buckets. Screws around outside lip are for eventual LST.

9. Drain - (can't really see it from pic) Pots are over a drainage tray that is plumbed into air-conditioner condenser drain. I can overwater and flush without moving plants from cab.

I regret not taking pictures during construction, but I was in a building frenzy. Sorry.
I don't really cover it all in this post, so feel free to ask any questions or make any suggestions. Thanks for your time and feedback.

[Headless Hornet]

Here are move detailed pics. Last pic is back view of cabinet (cannot be seen from attic access/storage area)

[up4anything]

nice job. the attic temps would worry me, but as long as you have it taken care of, you should be fine. You may want to get a second fan just to be redundant. If one fails, you're not completely screwed.

[ratatata]

Your preparations and growbox look great, good luck.

[Headless Hornet]

Pic 1
Here is a close-up of the cabinet corner. You can see the thickness of the wall panels as well as weatherstripping. Door is lightproof and very nearly airtight.

Pic 2
Here you can see more of the hood and exhaust vent.

Pic 3Here is the bottom tray and intake vent. You can't see, but the drainage tray is plumbed in from below to a drain. With all my ventilation, I've been having very low humidity (around 20% or less) I'm now trying to use the egg-crate mattress material to humidify. (it goes under drainage tray and is saturated with water once a day) seems to work ok so far...humidity now about 35%...i'm keeping an eye out for fungus on the egg crate though. I'm not sure it is the best solution.

Any Suggestions??


Pic4
Close-up of cabinet latches and pins. There are four total. Can also be padlocked shut if necessary.


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[bubbaclaus]

wow looks cool so far, I'm gonna keep an eye on this thread, I have similar attic probs I need to overcome in the very near future!
Good luck!

[ratatata]

Mate, I recommend using something else to humidify. A cheap humidifier should do.

[Headless Hornet]

Thanks to everyone for their input. Keep it coming.

I didn't like my humidity fix either. I'm going to try something different for a bit.

I've put a plug in the drainage tray and filled it with about an inch of water. I put a humidifier wick over the intake, extending it down into the drainage tray. So far, it has raised humidity about 15 points which is acceptable to me.

It acts pretty much like an inline humidifier. I'll drain the tray after every watering and refill with fresh water (and maybe a drop or two of bleach if things start getting nasty). I'm gonna keep a close eye on everything.

[Headless Hornet]

Been busy with school, but will continue with the specs...

Thanks to everyone for viewing this thread.

Since the number one rule of growing is "tell no one" it's nice to have a place to show off your work relatively safely.

I'll try to give some more specs on my grow:

Soil:

I used a custom mix with a local nursery's organic potting soil as the base.

I added several amendments (I tried to sort-of average all the soil mix recipes I found online - erring on going with too little of an additive than too much)

Organic Potting Soil
Worm Castings
Peat Moss
Perlite
Vermiculite
Blood Meal
Bone Meal
Dolomite Lime
Epsom Salts
Liquid Kelp Fertilizer

I mixed it all up in a rubbermaid tub, moistened it, and let it sit for about 3 weeks. I mixed it about every other day.

My biggest problem is PH though. For whatever reason, (I think the local potting soil is alkaline) I originally tested my mix at a PH of about 8. Waaay to high.
Over the course of the last two weeks, I added more peat moss, some sawdust, vinegar, and lemon juice to it. I only got the PH down to 7 or 7.5, but by that time it was time to plant. I should have got the PH under control before planting, but beginners make mistakes. I hoping this mistake doesn't turn out to be fatal for my first crop of girls. I'm slowly bringing it down...so far so good.

[Headless Hornet]

Seeds:

I chose Northern Lights #5 for my first grow. NL is supposed to be about the easiest to grow, it has a very low odor, and is a short compact plant.

I ordered the seeds from HGS. (I don't necessarily recommend HGS, but they worked for me this time).

Before receiving my HGS order, I also ordered some Joey Weed NL x C99 beans from HD. I wanted to hedge my bets in case HGS didn't arrive.

Long story short, HGS arrived first (HD about a week later...I will use those for my second grow). I started germination on February 19th.

Germination:
Standard paper towel method, germinated 9 seeds, all of them cracked. 100% germ!

Seedlings:
I planted the seeds in peat pots (I won't use peat pots again...I've heard too many negative things.)
I let them sprout in a mini homemade greenhouse and a 24" T12 fixture with one WW and one CW bulb.

All nine sprouted, I chose my favorite six to be moved into the cab right under the 250W (i started with the light way up, and gradually moved it down) I used my original sprouting light as a side-light in the cabinet.