DIY: A new angle on light proof vents

[prophecy]

Just to be 10000% sure that light doesn't enter the room. You can put a box on the outside or inside (doesn't really matter) but a box with no bottom. I think with a box over it its 110% lightproof!

 

[prophecy]

Hi Barth. For your grill, once you have ensured the flow is unblocked beforehand (second cab? 4" hole? huh? I will just assume you know what you're doing in that dept. Hoosier's airflow thread is the place to learn), your 6" exhaust equals 28.3 sq inches. So to follow the dummies guide to intakes (2x) you will need your intake area to be 56.6 square inches of free flow.

We need 56.6, plus the grill will be blocking roughly one third, so we want 56.6 + half of 56.6, which is 84.9 sq in. You need 84.9 sq in of my grill to have 2x intake. Type this number into a calculator and hit "sqrt" and it gives us 9.2. Your grill, using the same fin thickness, and spacer thickness as mine, needs to be at least 9.2" x 9.2".

Let's look at your 5" restriction which is now causing you problems. We take the 84.9 (total grill size needed) and divide by the restricting dimension. So 84.9 divided by 5" and it equals 16.98 so lets call it 17. Your grill can also be sized 17" x 5".

I always go as large as I can with intakes as long as it doesn't drop negative pressure enough to allow smell to leak out.

These calculs are good but ingore the size of the room!?!?! According to your calcul...I would need a same intake size for my 6 inchs fan that have 424 CFM and my 6 inchs fan that have 309 CFM. Both are same size but doesn't have the same airflow...! You sure those calcul are good?

 

[tony666]

I used plastic corner guard. $6 for 8 feet. Can cut with a razor blade. Sturdy, light, cheap & thin for max air flow.

 

[Ghostwolf]

Greetings tony666 that is a very good idea for material to make light traps. The angles are already made. And they're cheap and light weight. "Go in a good way"

 

[heady blunts]

scrub-

just wanted to say thanks for this sweet idea. i built one out of wood angle and i love it. but like an idiot i placed it between my veg and flower room and now i'm trying to figure out a way to further light proof it. i'll probably build a baffle, but i wanted to simultaneously give you props and ask your advice.

thanks for sharing your considerable skills!

 

[Ghostwolf]

A small up date I just found some small corner guard in the guy across the streets stuff he was giving away and moving out and I got from him a bunch of cool stuff some of which was that guard. I'll make some light traps from that now too. good idea Tony666.

 

[growingcrazy]

I just used regular 3/4 outside corner trim from depot. $4 for 8 ft and simple to cut,paint, and install. Like the piece on top but the cheap foam type.

 

[sci-fi]

If you clamp it down you can cut w/ a chop saw using a Non Ferrous blade just as easy as wood.

 

[the gnome]

great idea scrub!
heres a very cheap way to buil them if you have the accesss to a metal brake.
vinyl siders use coated aluminum coil to fabricate stuff, like for facia's, window trim.
the coil is very thin, less than 1/64th of an inch maybe.
you can use the metal brake to bend the angle or pay someone to do it for you.
if you know anyone that does alum-vinyl siding can do it or many siding suppliers can make it for you, and most of the vents lengths can be made from throw away lengths of coil
since theres only one bend its as easy as it gets and your standard length is around
10 and 12ft
it would take less than 5 minutes to make 20+ pieces 12ft long
I only read the 1st page so if thi idea has been offered up my bad

 

[gumball]

i bet tile spacers would be good for spacing these out.

 

[growingcrazy]

I just cut a small (1/8") piece of the trim and use a piece at each end as a spacer between each full length piece.

 

[BYLROY]

I'm totally gonna make one of these. I'll probably just make two of them and mounted in a box so they are 100% light proof, or did you find a better way?

 

[pacoveli]

Thanks ScrubNinga for this Ideal I was able to make one using plastic corner trim.I cant believe how easy and cheap it was total cost$15.


http://www.icmag.com/ic/member.php?u=42347

 

[StealthDragon]

These are some older pics from my last build..forgot to put them up.





like Arobskittle, I used the clear corner guard from homedepot with weatherstripping for the spacers...applied a generous amount of carpenter's glue and painted it black several times. I used some of that wood angle to make a strong frame for it. It's 99% lightproof but it's behind a thin layer of fabric that blocks the rest.

Thanks again Scrub! Without your lightrap idea I would probably have some crazy box sticking out the side. I also would have had to compromise some room on the inside of the box.

 

[Randybobandy]

Check this out

http://www.amscousa.com/Door_Hardware/Lites_and_Louvers/Anemostat_Door_Louvers_Inverted_Y.htm

 

[ScrubNinja]

Cool stuff!! Thanks for the replies and the pics especially.

And Randy, wow, excellent find. There you go.

 

[ScrubNinja]

These calculs are good but ingore the size of the room!?!?! According to your calcul...I would need a same intake size for my 6 inchs fan that have 424 CFM and my 6 inchs fan that have 309 CFM. Both are same size but doesn't have the same airflow...! You sure those calcul are good?

Hiya prophecy. My recs are just for a minimum, and you should go as big as possible imo. But most people here (and me in my calcs if I recall correctly) run off the very simple formula of: intake size = 2 x exhaust size and it seems to work fine. It's not that you should ignore the size of the room. It's more like you should take that into account when designing your ventilation system as a whole. Which no doubt you did. So you should be fine, if you did.

So it's months later (sorry, had no internet) - did you try it and was it fine?

 

[señorsloth]

wow! i must say i really wish i had taken a closer look at this thread! i have been searching all over the net for more info on light traps, and who woulda guessed it was all right here, hidden in the replies of a diy! some of these designs deserve their own diy, lotta great ideas! i just wish i had found it before i spent 2 hours walking around menards, and too many days scouring the internet for ideas on how to build one. i had seen the original diy but i thought the fins were too fat to be effective(no offense intended),i recently decided to try and find a thinner material, and incorporate a second bend, so that the trap would be 100 percent light tight. with my larger sized wardrobe cabinet i needed a big light trap and i couldn't have any leaks because my strains are rather sensitive.

i ended up finding the "V" shaped lengths of metal used to protect the corners of drywall(i think i saw some of you guys using it in this thread, again, wish i had known about it!), they are super duper thin, paper backed for easy painting, and cheep! less than 2 bucks for a ten foot piece, i figured i wanted my trap to be 10 inches by 10 inches with .25 inch spacing, which required 90 feet of material, for spacers i originally just used a piece of wood, that happened to be quarter inch, cut into half inch strips, then cut to fit each bend, held together with super strong double sided tape, it worked great, but i thought i could space them much more so i took it apart this morning.

i spent way to long trying to figure this stuff out and it seems you guys already did all the work for me! i overlapped 2 ten inch pieces of "V" shaped material to form a "N" (you guys figured that out already i see),this seems to be a really light tight setup, though it obstructs the air a lot so i'm trying something different. i have some pretty dense 5/8 inch thick weather stripping that i'm going to use to space the thin metal veins apart, then i'll check for light leaks, if it does leak light i can simply squeeze the trap till the spacing is just right, thanks to the weatherstripping(ANOTHER idea you guys already came up with), lol i make furniture for a living so building a frame that will hold it compressed or otherwise should be no problem and the foam rubber spacer material should dampen any vibrations too, which is a plus i guess lol.

i need to go over this whole thread with a fine toothed comb before i re assemble this thing, but it seems to me that at least a few of the people in this thread have found ways to improve on the original design significantly, not to offend the OP in any way but i think they should have their own stickys as well, so that people know the other designs exist. to be honest i read the tutorial, and didn't bother with the replies because a lot of times they are just ten pages of people saying things like " good job!" or "nice work!"....i am thinking about documenting my final build this weekend once i have the frame ready doodled around with the correct fin spacing...i don't know though, since it seems most of my ideas were already thought up and documented, my diy would basically be a hybrid of many other peoples ideas and i'm not sure i should make a thread that could in any way take credit from people smarter than i for myself...

 

[kgb424]

why couldn't you tack weld them instead of using epoxy, to assemble the light scrubbers

 

[wrekstar]

could this be done with card or paper?