How Light Tight To I Really Need To Be?

[Moss]

I'm in the process of prepping a cabinet so I'm ready to go once in a few days when I'm legal.

 

The doors of the cabinet aren't lined up very well, I'm using some heavy duty tape to make flaps that cover the seams, they are working pretty well but a tiny bit of light is getting out. I use 14w CFL's as the lighting for the room the box is in, which are about 5 feet or so away from the box so I don't see these little leaks as an issue.

 

Any thoughts on this issue?

[Ian]

Just run a heavy tarp over the top of the whole cabinet covering doors etc, use like curtain when checking.

 

[ edit: you could also run panda film on inside ]

 

Light is a big no no !

 

Regards

 

Ian

[Moss]

I have considered that but would like to avoid it as I'm trying to keep it as stealth as possible. I just finished the tape job and it's better than I expected. I only have 2 slivers of light still showing though and it's not a straight shot, it's reflecting off the tape. I think if I get some weather stripping it should take care of it.

[boroboro]

I saw someone sealing up a cabinet using material from frilly, fuzzy scarves. He just stapled it to the inside sealing edge of the doors, and it sealed out light pretty well as the door squished the material when closing.

 

Plus it gave the cabinet this funky old 70's shag carpet look when it opened....

[old-hobo]

to seal my box I took an old refrdgerator magnet seal and took thin strips of steel around the faceing edge seals just like a tru fridge.

[TheFlyingBuddha]

Heres a good rule of thumb, if the area your working with is big enough to sit in, go in side and have someone else close it behind you. Sit in there for a good 5-10 minutes to let your eyes adjust to the darkness. If you can hold your hand out and still see your fingers theres too much light.

 

It also helps to show you where the light is leaking in, use a marker and circle the spots where you see light coming in the inside, and it will help you remember what spots need to be fixed once the lights are back on.

 

TFB

[rbuck1501]

It's critical to keep the 12 hour dark period during flowering COMPLETELY DARK. NO LIGHT LEAKS. Light leaks are one of the main cause's of hermie plants and seeds.

 

With all the other stresses from indoor gardening, light leaks are one of the easiest to address. Weather Striping works great for sealing doors, air conditioners, ducting etc. There are self sticking foam rubber type's in in different thicknesses and in rolls you can cut to fit, or a none sticking type you can use to stuff cracks or staple into place. And caulk is cheap and effective for sealing cracks also.

 

Going into your room after lights out to check for leaks is a good idea. Be sure to turn ON any lights out side the room that could cause a light leak (consider the sunshine also) and wait for 10-15 minutes in the dark room for your eyes to adjust to the darkness, so you can see any leaking light.

[Moss]

Thanks everyone.

 

It's not big enough to sit it and look, I did take my phone and set it in there with the video camera running to see if there was any light I could see, I couldn't but the camera also sucks.

 

The tape job I did on all the seems is great, just too small areas where I can see light escaping, I'll get some weather stripping next time I make it out to the store.

 

Right now I'm on to intake and exhaust. 2.5" PVC for the intake 4" PVC for the exhaust both with matching sized axial fans. I hope that will be enough (box is 42" tall x 36" wide x 16" deep), intake is going on the lower right and the exhaust at the top left.

[Mikel2425]

Hope you didnt use duct tape.It will dry out and fall off.Use HVAC foil tape.Some minimaul light wont hurt plants.They get the moon outside and that doesnt hurt them.Iv had the light on for an hour during dark period with no problem.

[Moss]

I used 3 different kinds of tape actually. Gorilla tape, then covered that with white duct tape, then in the seams where the tape was sticking when doors were opened or closed I used electrical tape.

 

I just finished it up, letting it run now to see how hot it gets.

[Moss]

Okay, it's been running for about 2 and a half hours. It's running about 83 degrees with 6 23 watt CFLs.

 

That should be fine I believe. When I actually start growing the lights will be set up differently so hopefully the real configuration will somehow drop it a few degrees.

[Mikel2425]

Not sure about the Gorilla tape but the other 2 will start failing soon.Duct tape just drys out and falls apart and looses it stick.Used it a few times allways does it.Switched to foil tape.Its made for duct work heat wont dry it out and is super sticky.

[oakparkmale]

I've been growing my own for several years and I recently ran into a lighting issue like yours.

 

I grow in a style that is called a perpetual grow. This is where you constantly maintain a

number of plants in all stages of growth. This requires me to operate 2 different and

separate growing areas. The first area is a nursery where the seeds are sprouted and

seedling spend their vegetative growing days under 24 hours of lights. The second area

is a flowering space where the seedlings are placed to flower. Both areas of in the same room.

The flowering area is an old 4x2.5x5 foot home made crate. The nursery area is an old book case

fitted with a door and is only 2.5x1.5x2.5 feet in size. Both areas have light leaks.

 

My last batch, 2 marijuana plants called Chrystal had a hard time flowering and the harvest

was mostly seeds. This was by design. I had a new pack of seeds from a breeder and when

first growing a new pack of seeds, I always pollinate the plants and take a harvest of seeds.

I had just written the slow growing off on the pollination. I had pollinated them at 2 weeks

when very little flowering had taken place.

 

I am in the process of flowering a new strain called Papaya. I grew out this strain before and

had a 300+ gram yield from 2 plants. The dry weight settled in at just under 3 ounces. Papaya

is a strong White strain with THC content above average in the upper teens. After 10 days of

stretching and 4 days of actual flowering, I began to wonder why the flowering on the plants

are far behind the expectation I am used to.

 

By a stroke of luck, I had remember the time the night before when the lights went off at 936pm.

And the next morning when the lights came on it was 9am. On top of this, I have a window in my

room that I like to have access to. Along with this, at 630am Sun fills my room with indirect

sunlight. I had to correct this now. The first thing I did was reset my timer so the the

light inside the box was set to the plants photoperiod of 12 hours of darkness. I also adjusted

my blinds so that less sunlight lit up my room.

 

Not only should you try to make the cabinet as light proof as possible, you need to make sure your

lights and timer are set correctly to give the plant 11 to 12 hours of uninterrupted darkness everyday

and that any sunlight, light from lamps and ceiling fixtures are to a minimum during the times the

lights in your grow cabinet are off. You should also check the time the lights go off, and the time

they turn on at least once a weak.

 

Good Luck!

[wolfgama]

I have a long 6 foot cabinet that stands 5 feet tall, I put two sets of florecent lights in and put my cloner and vegging plants inside that. It stays about 78 in there. I cover the front with some plastic with the black side facing the cabinet and the white side facing the plants in flowering in the room. I tuck it in each night at 7:30 and then I use blackout shades on my windows. Issue? Yeah!Light comes still in the flowering room because daylight saving time has moved the light of the sky to a later time! But in the morning when the lights come on at 7:42 (closest I could get to a 12 hour) My plants room also faces the big light outside by the polebarn. That filters in on the edges of the shades. But I have never had a bad problem! I do live in the middle of the woods so our sundown is earlier than if we lived in a field. As the stars shine, full radiant moons glow, a little crack of light shouldn't hurt your crop, but then I am not an expert, just an old Dutch lady that has grown for a year now! I switched from dirt to hydro, cleaner and faster and yet more detailed. I grow with a 600w and 400w side by side, more lumens than a 1000w and less cost of electric. Ok Kids, I am old and need a break from the chair! Peace and Love and Just Imagine!

[Grow Thread]

Heres a good rule of thumb, if the area your working with is big enough to sit in, go in side and have someone else close it behind you. Sit in there for a good 5-10 minutes to let your eyes adjust to the darkness. If you can hold your hand out and still see your fingers theres too much light.

 

It also helps to show you where the light is leaking in, use a marker and circle the spots where you see light coming in the inside, and it will help you remember what spots need to be fixed once the lights are back on.

 

TFB

 

the best info. in this thread!!

[rbuck1501]

Not all strains are sensitive to light leaks, but it only takes one plant to hermie or form male flowers to mess the whole crop up.

 

For smaller grow areas, turn the lights on in the grow box/chamber then (at night) turn the lights out in the room and look for light escaping from the grow box. Then seal any light leaks after your inspection.

 

Under the door light is a notorious problem. I use a piece of weather stripping on the back of the door, to block light between the bottom edge of the door and the floor from entering. Any heavy fabric along the edge would work too.

[Moss]

I got weather stripping today and have everything sealed up except the bottom of the door. The doors won't close with stripping on the bottom. I will figure it out though.

 

The biggest problem I have now is heat. Letting it run all day with 6 CFL's the temp hit about 90 with the house temp in the low 70's. I guess I'll need to put in another intake. Anyone know if a having a passive intake on the other side of an intake with a fan will work?

[ccpulsipher]

Okay, it's been running for about 2 and a half hours. It's running about 83 degrees with 6 23 watt CFLs.

 

That should be fine I believe. When I actually start growing the lights will be set up differently so hopefully the real configuration will somehow drop it a few degrees.

remember the plants are also going to cause the heat to go up i run mine at no higher than 80 they really like it around 77 so just watch the heat when the plants get in there

[Moss]

 

Okay, here is a quick drawing off my box and the ventilation system.

 

Top left is 4" exhaust, PVC with an 120mm axial fan attached.

 

Bottom right is 2.5" intake, PVC with 60mm axial fan attached.

 

Box is 42" tall x 36" wide x 16" deep

 

Any idea of what will get temps lower?

 

I'm thinking add a second intake to the bottom left.

[simonbloomfield]

 

Okay, here is a quick drawing off my box and the ventilation system.

 

Top left is 4" exhaust, PVC with an 120mm axial fan attached.

 

Bottom right is 2.5" intake, PVC with 60mm axial fan attached.

 

Box is 42" tall x 36" wide x 16" deep

 

Any idea of what will get temps lower?

 

I'm thinking add a second intake to the bottom left.

I use the silver foil tape (home Depot) to seal all of my cracks. You can use the foam 1 sided tape to seal your leaks. And then Go over it with the foil tape. You can layer it if it starts to get wrinkled around the edges and want it to lok nice