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Your thoughts on my new cab design?

ramshambles

New Member
Hello good people!

So I've decided to grow my own plants. It'll be my first time grow. I've decided to document my efforts over on the 'Grow Journals' forum once I get started with the build. I've done a fair amount of research, and knocked up a design using Sketchup, but as we all know, theory is not necessarily going to work in practice. So my question to you good people is, do you think the following design will work?



The top chamber will be for budding and will house a 400w hps with an ebb and flow timed hydro set up. The exhaust vent up top will have a carbon filter installed over it and be vented passively through holes in the top of the unit. The bottom chamber will be used for vegging with two 125w cfls and a drip fed hydro system.

My plan is to have a perpetual grow where each time I'm ready to move from veg to flower I will take clones to replant in my veg chamber.

My main worry is i wont be able to keep the heat down in the bud chamber. If worse comes to worse I can install a second exhaust/carbon filter up top over the hps.

I'm hoping to grow some northern lights to get me started.

Any tips or advice greatly appreciated,
Peace.
 

Graytail

Plant of the Year: 2014 - Plant of the Month: Dec 2014 - Nug of the Month: Feb 2015, Mar & Aug 2016, Dec 2017, Aug 2018, Jan 2019 - Nug of the Year: 2017 - Photo of the Month: June 2018
Re: Your toughts on my new cab design?

I've been trying to work out a similar cabinet for myself and it's nice to see it sketched out. You have the same 7 foot height.

The problem I keep running into is light clearance. I think your proposed 400W hps is going to be an issue. A 400W shouldn't be closer than a foot from the canopy and it's almost a foot tall itself. And for that cubic volume, it's a lot of light ... and heat. A 250W hps would still give you 33.3W/sqft and that would bring that clearance down closer to 1.5 feet. I get an ounce per sgft and I run slightly less than that in an enclosed, highly reflective space. Otherwise, you go with floros which have their limitations, too. Even LEDs need some significant clearance. One spendy option you might look into for that space is one of those big induction floros. Search "induction grow light".

I want mine strictly for veg, so I can go with CFLs - 4 inches themselves plus 2 inches from the tops = 6 inches total clearance.
 

ramshambles

New Member
Re: Your toughts on my new cab design?

Shitballs! I've already ordered this 400w hps, my two cfls and the fans. I may be able to save some space in the veg chamber by dropping the hydro system. I think my best course of action now is to build the unit and set it up for a dry run for a day or so to check temps and whatnot. If it's not possible to make work I'll have to heed your advice and drop the 400w hps out for something a little less potent. In the meantime I'll start checking out some alternatives such as the induction grow light you mentioned.

As an aside, I was toying around with the idea of rigging up some sort of PC water cooling system to the light to get rid of some extra heat but I haven't done any sort of homework on it yet.

Cheers for the input Graytail.
 

ramshambles

New Member
Re: Your toughts on my new cab design?

Hopefully with this installed I should be able to have the light around 8 inches over the canopy without any leaf crisping issues.
 

The303Stoner

New Member
Re: Your toughts on my new cab design?

my plants are less than a foot from my 400w with no glass and are fine I pump in cool air in to the hood and remove the hot air through my filter and out the room.
 

BudBGrowin

New Member
Re: Your toughts on my new cab design?

If you get a nice fan and up the ventilation it might still be possible to run a 400w light in that space. I have 300w running in a 2x3x5 area at 74 degrees with an ambient room temp of 71. It is cool tubed though. Then if you could create a natural draw up through the bottom compartment to the top without leaking light into the flower chamber you can use 1 fan and filter to clear the whole cab. t'5s would do nicely for the bottom as they have a low profile and relatively low heat output.
 

ramshambles

New Member
Re: Your toughts on my new cab design?

Cheers for the suggestions. Unfortunately I got ahead of myself and ordered the 400w hps, ballast, reflector,two 125w cfls and four fans before really thinking anything through so I'm going to try and work with what I have for the moment.

Here's the revised plan to handle the temps. The ambient temp in my room this time of year is around 57f with no heating on. It could get to 75f on occasion during the summer but rarely.



Still waiting on a few bits and bobs to get started on the build. At least the veg should be up and running in a few weeks. I'll update with temps and whatnot when I start flowering.
 

Graytail

Plant of the Year: 2014 - Plant of the Month: Dec 2014 - Nug of the Month: Feb 2015, Mar & Aug 2016, Dec 2017, Aug 2018, Jan 2019 - Nug of the Year: 2017 - Photo of the Month: June 2018
Re: Your toughts on my new cab design?

If you have intake temps of 57 degrees, you could be just fine with that big ol' 400. Not so bad.

... still not a lot of clearance ...

:3:
 

ramshambles

New Member
Re: Your toughts on my new cab design?

If you have intake temps of 57 degrees, you could be just fine with that big ol' 400. Not so bad.

... still not a lot of clearance ...

:3:
Fingers crossed! I've around 10-12 inches depending on how tall my buds grow.
 

BudBGrowin

New Member
Re: Your toughts on my new cab design?

I agree those are nice ambient temps. It looks like in your design you have intake and exhaust fans. If you do have issues with heat you could make them all exhaust fans and allow the natural draw in due to the negative pressure the fans would create, as well as drawing from the lowest point to keep incoming air at its coolest. Also I'm not sure what kind of carbon filter you have. Is it a bought unit or are you making your own? The tricky part would be allowing the air to flow without letting the light get into the bloow camber. Here are some suggestions I did based off your plans.
 

ramshambles

New Member
Re: Your toughts on my new cab design?

Thanks for the suggestions biscuittent. I'll move the two exhausts at the top in the center as you have suggested so they're over/as close as over the center of the light as possible.

I'm going to be making my own carbon filters so ill have a bit of play on that end regarding how much carbon is used.

At the moment I'm thinking with the lip on the edge it should keep my intakes seperate from my exhausts and allow the intakes to suck somewhat cool air from the room while allowing all the hot air to rise up the side and out the top to escape back into the room. It sounds good on paper but whether it works or not is a different story.

Im trying to make do with computer fans if possible to keep it somewhat stealthy. It's in shared accomodation. The housemates are cool but guests are best kept clueless. :)

The diagram should explain what I'm hoping for. On the top of the unit there is 100mm clearance then the ceiling. Same on the side. 100mm clearance to the wall. Only the holes marked with x's are going to be used initially to see if temps are ok. I was just fuckin around with ideas adding the rest of the holes. If more venting is needed after that I'll add it. I've a load of old broken laptops knocking around I can cannibalize for vents if I need more cool air.

 

BudBGrowin

New Member
Re: Your toughts on my new cab design?

Cool it sounds like you have a good plan on what to do. One other thing I did notice is that in your mock up the light reflector tube is turned against the slope. Maybe if you turn it 90 degrees it will give you a little more height than when it has to hang a little lower from the angle. Plus then you could even use the slope as a slight reflector! If you do have a reflector like that somehow Im sure at a hardware store they might have some ducting and flanges somewhere you could use to make a home made cool tube and filter using the draw from those top two fans but it would come down to space in the cab.
 

BudBGrowin

New Member
Re: Your toughts on my new cab design?

Also you might be surprised how much light can reflect from an exposed hole like your vents. If stealth is somewhat of an issue it will be quite obvious when the cabinet is haloed in a warm orange glow. That lip looks adequate for separating the air intakes/exhaust but light will need a few more baffles probably. Looks good though!:thumb:
 

ramshambles

New Member
Re: Your toughts on my new cab design?

Nice one for the light position suggestion! Should workout nicely with the slope. As for the light, I'll have to deal with that when everything's up and running, should be manageable though.

I think I solved my heat issues definitively. My old man had an 60cm extractor hood knocking around in the shed, brand new aswell. :)I opened it up and took the fan out of it. It's a fuckin beast of a thing, not too noisey on low and it even has a three speed toggle switch on it. These filters fit right onto to it but I'm not sure whether they'll handle the small entirely. If not I'll just slap a bigger one on it.

I'll post up a few pics when she's finished.

Thanks again for all the tips.

Happy new year!
 

BudBGrowin

New Member
Re: Your toughts on my new cab design?

Sound great if you get some pics up I would love to see the finished box! Happy new year to you and good luck with the build/fill.
 
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