does reflective mylar really work?

jknight4652

jknight4652

Active Member
i have a 6ftx18inx3ft metal cabinet and i have put the mylar in it but i have taken it down 3 times to move some thing around and im looking at adding 3 cfl lights about half way down mounted on the 2x4 skeleton inside...and i have enough to put back in there ..buts its a pain in the ass to with work in and keep tight...is it worth putting it back in there? isnt there a paint that is supposed to work just the same... another is how many people use reflective stuff in there cabinets etc?...i have seedling going now but soon ill need to put them in this room again under the t5's....
 
Its a BIG no-no, but i have been using Tin Foil in my grows for quite a while now, with CFL-s its not too bad, actually i've managed to increase my light density, white paint will do fine
 
you need to have one or two panels that the mylar is attched to that can be moved so you can work then put back when you are done
 
Behr Ultra Pure White Flat wall paint. (not gloss or semi)

It's actually superior to mylar, not a few percentage points behind it.
 
one day you will be sitting around your house and thinking of how the hell can you make your grow cooler. You will be all outa ideas. Then you will remeber mylar. It will be after co2 after continous trimeter and after a 2nd house. Lol.
 
Mylar isn't BS. It reflects around 97% of the light that hits it, compared to the 80% (ish) of flat white paint. That may not seem like much, but it all helps.

The downside to mylar is that it is relatively expensive, and hard to install without creasing, tearing etc. It also needs cleaning regularly to maintain optimum reflectivity.

The upside is that, done well, you get more from your lights, for a small one-off cash outlay. Plus, it looks cool as hell. :D
 
Mylar is only more reflective because it's directionally reflective and that directionality makes it inferior to flat white paint for our uses. Figure out the angles in almost any grow situation and you'll see all that light is directed innefectively away from the plants.

There are tons of reasons why paint is better than mylar and I laid it all out in that recent myth busters thread if you want to check it out. Start at the last page.

I first started growing in the late 80's and never stopped learning all this time. Don't play me off like a fool. I'm not the one who needs to learn more about this subject.
 
OregonMeds said:
Mylar is only more reflective because it's directionally reflective and that directionality makes it inferior to flat white paint for our uses. Figure out the angles in almost any grow situation and you'll see all that light is directed innefectively away from the plants.

There are tons of reasons why paint is better than mylar and I laid it all out in that recent myth busters thread if you want to check it out. Start at the last page.

I first started growing in the late 80's and never stopped learning all this time. Don't play me off like a fool. I'm not the one who needs to learn more about this subject.
Click to expand...

No need to get defensive, i'm just stating the facts as I understand them. Do you have a link to the thread so I can see what you are talking about more clearly.

I hear what you are saying about directional reflection, but i'm not convinced that all the light is directed ineffectively away from the plants, as you have stated. I'd say that it would very much depend on the individual setup (lights, room dimensions, etc.). I also think that the fact that white paint absorbs 20% of all light that hits it must count against it's effectiveness, even though it diffuses the reflected light better than mylar.

I have used both paint and mylar over the years, and not noticed any real yield difference, to be honest (although i haven't exactly checked). I would be interested in a comparison of the two surfaces, with a light meter at various places in a grow room. Have you done anything like this?

I'm not questioning your knowledge on the subject, and will concede whatever point you like, if firm evidence is there to support it. I am not egotistical enough to think that I know it all, despite the fact I have been growing for a long time myself.
 
Sorry about the attitude. I didn't mean to come across like I know everything either, it's just that one of the posts I may have misinterpreted completely and I'm still not sure what eharmony meant by:

"one day you will be sitting around your house and thinking of how the hell can you make your grow cooler. You will be all outa ideas. Then you will remeber mylar. It will be after co2 after continous trimeter and after a 2nd house. Lol."

Seemed to be completely dismissing what I said as BS, but now I realize maybe that person was referring to foil. Still not sure what he meant.

Anyway I will start a new thread on the subject. Give me an hour or so though, I have to take care of some other stuff first.
I've tested everything from paint to mylar to space blankets to mirrors and even first surface mirrors, but I didn't keep records or anything like that it's all in my head. (Keeping records on illegal activities didn't seem wise at the time.)

 
Mylar is most effective when it is completely flat with a clean surface. Any crinkle will lower its reflectivity greatly, although it will still reflect decently in my opinion.
Also mylar seems to be great for keeping light out of an area. I use it in my cabinet and it blocks most of the light coming out of the cracks leaving very little work left for me to do to keep the light from leaking. I guess for my situation mylar is the better choice, for others it may be another option.
 
Nocturn3 said:
Mylar.... Plus, it looks cool as hell. :D
Click to expand...

heh heh. i've worked with mylar before... knowing how its important to string it up tight. i did a good size room with it recently... taking care to get it very taut. 4 hours later it was all wrinkly.

ah well. it was easier and faster than painting the whole room. and it will still work decent. if theres a next time i'm going with panda plastic though.

and it -does- look cool as hell :D i remember the first room i did with it (about 15 years ago)... was about 7' by 7'... i'd open up the door and it looked like something on a spaceship.
 
What would be a good reflective thing to use if I don't have a reflective surface to paint on? My walls are made out of thin black plastic! What should I use for reflection?
 
You must log in or register to reply here.

Similar threads

shotnva777
  • Locked
Help with nice/cheap LED? *CRAZY PLUG*
2
Replies
34
Views
3K
sunni
sunni
Thatoneguyyouknow_
Long time grower returns to the life
Replies
4
Views
810
Thatoneguyyouknow_
Thatoneguyyouknow_
Hobbes
Anyone try The Flower Mill grinder?
Replies
0
Views
378
Hobbes
Hobbes
Pauly1118
24’x10’ Room w/ 10x 1000w Lights
2 3
Replies
46
Views
2K
LeastExpectedGrower
LeastExpectedGrower
E
Need Help From Someone Who Is Familiar With Autoflowering Outdoors.
Replies
5
Views
1K
Humanrob
Humanrob
Back
Top