Help me design my new grow cab

[FONT=Tahoma, sans-serif]Looong time outdoor grower being forced inside for various reasons and not under ideal circumstances. This cabinet will be in a garage with no air conditioning and very poor air flow…...in Florida.[/FONT]


[FONT=Tahoma, sans-serif]Not much I can do about the space without spending thousands and drawing attention to the structure. I realize it may not be feasible to use this cabinet during June – August and I'm OK with that.[/FONT]


[FONT=Tahoma, sans-serif]I'm envisioning a box with the following outside dimensions: 3 feet wide, 7 feet long and at least 5 feet high. Construction will consist of 1/4” to 1/2” plywood outside of 2x4 framing and 2” rigid insulation board on the inside. [/FONT]


[FONT=Tahoma, sans-serif]Contents will include:[/FONT]


[FONT=Tahoma, sans-serif]5,000+ BTU portable A/C[/FONT]


[FONT=Tahoma, sans-serif](8) Cree CXB3070 COB LED with Meanwell driver[/FONT]


[FONT=Tahoma, sans-serif]Dehumidifier if necessary[/FONT]


[FONT=Tahoma, sans-serif]Tropf blumat system w/resevoir[/FONT]


[FONT=Tahoma, sans-serif]240 CFM fan with carbon scrubber[/FONT]


[FONT=Tahoma, sans-serif](2) oscillating tower fans[/FONT]


[FONT=Tahoma, sans-serif]
Unlabeled squares are the lights. [/FONT]


[FONT=Tahoma, sans-serif]I currently have the 240 cfm fan for the scrubber and all the LED/driver equipment[/FONT]


[FONT=Tahoma, sans-serif]Soooo, my questions are as follows:[/FONT]


[FONT=Tahoma, sans-serif]The fan should turn the space (approx 100 cu ft) through the scrubber twice a minute. Is this too much?[/FONT]


[FONT=Tahoma, sans-serif]Given that ambient temperature outside the box will often be close to 100 degrees, is this enough A/C?[/FONT]


[FONT=Tahoma, sans-serif]Is this enough space for an A/C unit to work correctly?[/FONT]


[FONT=Tahoma, sans-serif]I plan to put the A/C in the middle of the box and two 30” x 30” grow spaces each with two LEDs – how many plants can I realistically put in each space?[/FONT]


[FONT=Tahoma, sans-serif]What is the optimal plant height for these lights? [/FONT]


[FONT=Tahoma, sans-serif]Are the corner fans placed appropriately?[/FONT]


[FONT=Tahoma, sans-serif]Initially I plan on running an organic soilless mix and AACT cause that's what I know and it's one less thing to mess with while I get everything else dialed in. I also thought that using blumats would help alleviate humidity swings that might occur with hand watering or hydro (but I could be completely wrong about that as well)[/FONT]


[FONT=Tahoma, sans-serif]So tear this apart, improve it, help me make it work better.[/FONT]


[FONT=Tahoma, sans-serif]Note: this proposed set up is the minimum in my mind for this to function. I'm not really interested in tricking this out with automation, fancy controls or anything beyond what will make it purely functional to begin with. I can always upgrade down the road.[/FONT]


[FONT=Tahoma, sans-serif]So who's up first??[/FONT]

First note: Apparently portables suck ass compared to window shakers in terms of cost, efficiency and producing heat in the grow space. I briefly considered a mini split, but I really don't want to have any new A/C equipment suddenly appear on this structure so now I'm thinking I have to duct a wall unit to accomplish what I want.

If you use a window shaker mount it out the wall of the cab as if it was mounted out a window this will leave most of your heat out of the cab and if its to small u can always upgrade it from with a larger unit fairly simply. This will help u avoid building a box for it inside the space as well. Good luck I'm all subbed up! BCSticky

I'll just agree with the others and say that in a cab of that size a flush-mounted window AC could actually end up saving you space and money, and be more efficient to boot. The trade off is the exhaust end of the AC will be sticking a couple inches out of the back your cabinet.

Thanks BCSticky, you're dead on in that thought. Window units can only have the front 4-6" of the unit in the grow space or you will be wasting the cooled air that the unit generates.

Since the whole thing will be in a space that is often at 90-100+ degrees, the back of that unit will have to have two separate ducts - one to bring cooler air from the outside to the unit and one to exhaust to the outside the significant heat the unit produces to make cold air.

What I guess I have to figure out is how to duct both of those and what other equipment (duct fans) I'll need to move enough ambient air to make the unit operate correctly.

Here's a link to illustrate what I'm talking about: https://www.icmag.com/ic/showthread.php?t=95491

Your ac unit will still produce cool air with those ambient temps in your garage unless you have an excess heat buld up in your garage it should work just fine at 80 to 100º it should produce 65º air without issue thus cutting down on your ducting work. BCSticky

hmmmm window shaker over portable....
bout to go thru same transition,same state....building room out in.garage as well, those J-J-A months are gonna be a.scorcher thats for damn sure...ill be.chking back to hear the updates..GL DP...be safe brother..

DP's movin on inside. Good luck!

One thing for sure DP, if you go this route https://www.icmag.com/ic/showthread.php?t=95491, you'll want to research the reliability of the wall shaker unit... What a PITA it's going to be to have to service that machine after it's all ducted up.

True dat fooool! Pain in the ass. Good point coba! Do any maintenance needed first. Id be wary of used unit for the simple matter of rebuilding the damn thing if it fails.

Took me about an hour just to rip the damn thing apart. Apparently i splurged on the good foil tape for that job and it backfired. Had that shit everywhere, doesnt want to peel off.

BCSticky said:

Your ac unit will still produce cool air with those ambient temps in your garage unless you have an excess heat buld up in your garage it should work just fine at 80 to 100º it should produce 65º air without issue thus cutting down on your ducting work. BCSticky

Click to expand...

Probably start without ducting it but by mid June I'm sure it will be over 100 in there and only get hotter if the unit isn't ducted.

bucketswithsoil said:

hmmmm window shaker over portable....
bout to go thru same transition,same state....building room out in.garage as well, those J-J-A months are gonna be a.scorcher thats for damn sure...ill be.chking back to hear the updates..GL DP...be safe brother..

Click to expand...

Strap in Buckets, this rides about to take off and there's no guarantee I'll land this bitch

Catatafish said:

DP's movin on inside. Good luck!

Click to expand...

Thank you Sir!

Coba said:

One thing for sure DP, if you go this route https://www.icmag.com/ic/showthread.php?t=95491, you'll want to research the reliability of the wall shaker unit... What a PITA it's going to be to have to service that machine after it's all ducted up.

Click to expand...

That's the ducting plan, plus I'll probably add a 6" duct fan to the exhaust run as well. It can't all be easy can it??

Catatafish said:

True dat fooool! Pain in the ass. Good point coba! Do any maintenance needed first. Id be wary of used unit for the simple matter of rebuilding the damn thing if it fails.

Took me about an hour just to rip the damn thing apart. Apparently i splurged on the good foil tape for that job and it backfired. Had that shit everywhere, doesnt want to peel off.

Click to expand...

Two 5000 BTU units are cheaper than a crappy portable. Plan is to go to Wally World or HD and buy the extended warranty so when they do crap out, I have an immediate backup and some recourse on the dead unit.

Unless I've figured wrong, A/C will make or break this so I'm willing to spend what I must to have redundancy and protect the grow.

Now that I've made that decision, I'm probably going to move the A/C to the end of the cabinet instead of the middle - with the corner fan(s) and scrubber I have to think that won't be a big deal.

So is anybody using temperature/humidity controllers? As the seasons change (well as it just gets progressively hotter) I would think it would be easier to adjust cooling with one of those rather than manual trial and error.

Also anybody got and suggestions for corner fans? I was thinking a 36" oscillating tower fan and follow the warranty plan like the A/C units. I bet those fans crap out pretty quick running 24/7

Bumping for feedback - anybody????

I'm starting construction, final dimensions should be approximately 84L X 40W x 78H or just over 150 cubic feet.

Will hopefully have the cabinet built and insulated by the weekend (being optimistic here) then on to the wiring and light construction & wiring portion.

Would love to hear opinions on fan placement, scrubber placement and C02 controller placement so I can have a wiring plan that makes sense.

You might be a little shy on lights. The 3070s cover a square foot very well at 50w. You are trying to cover a 21 sq ft area with only four. Are you running them harder than 50w? Do you plan on just keeping plants under the lights or trying to cover the whole footprint of the cab?

No, I know I'll need more light to cover the space, I'm just starting with these four until I have some sort of grasp on what temps will be like.

And the first major change happened today - was setting the stop on my saw to cut the long rails for the framing when a client called. Talked for a minute before going inside to finish the conversation.

When I came back I failed to double check the setting and cut all the long rails 6" short! Not a huge deal, I lengthened the width rails to 40" so at the end I only lose 10 cubic feet.

Having issues with my computer, when I sort that out I'll throw some pics up.

'measure twice, cut once' is a good rule... but if im smoking I usually have to measure at least 4 times

Subbed. Hope to build my own LED's in the future, gonna follow along with yours. G'luck!

Four times in Imperial and once in metric

Glad to see some interest!!

Glad to see some interest!!

Welcome Lake Effect & Mikell!!

I've swung a hammer enough to know to avoid my thumb at all costs, but now it's time to get down to business.

Here is the base of the cabinet.

One of the major components of this plan is insulation - it gets hot as the crack of the devils ass around here far more often than is comfortable for man, beast or plant. This cab will be located in a garage which has poor air exchange at best and gets wicked hot for 6 months out of the year.

This is a sheet of 2" insulation on the bottom of the unit, Simpson Strongtie plates screwed into place for the uprights and waiting for the caulk and decking to finish the base.