How to light proof intake??

[gsxxer]

i know people use dark room louvers but how big do they come?

my box is 4 x 12 x 7.5 ft tall

Does anyone have the formula to how much square footage of intake is needed?

i remember i saw it on og but im not sure... i know i see 8"x8" louvers alot, but i would need like 20 of them for my size room.

i cant use co2 yet, so i need a passive intake, but i dont really want to use pvc pipes with 90's if i dont have to.

any ideas?

 

[NiteTiger]

Section of dryer duct, and some stiff wire.

Glue wire to dryer duct, bend into U shape.

Spray inside with black spraypaint.

Done

 

[TheGhost]

Hi gsxxer,
A few questions:
How many watts?
Is your hood air cooled?
What are the ambient temps outside the box?

Your box is 360 cubic feet, thats huge! I have always tried to aim for watts / 2 to vent an enclosed space, but the ambient temps outside my box are high so you may not need to go to that extreme.
Louvers are okay, but an HPS or multiple HPS's in your case put out way more light than louvers were ever meant to stop.
90 degree bends are fine if the system is designed properly, yes you will hear alot of people say that 90 degree bends are no good, but when you really look at the problem it is usually caused by something else like not enough intake area or a convoluted design. I always try to aim for an intake area that is at least 3 times larger than the outlet area of my fans. (if you don't let em breath they won't work the way they should)

I hope that helps.

BTW. Nice work, I love big cabs.

Later Ghost