Mylar Hood !!!!!

[DonJones]

Well, of the two, I think I prefer the one you made out of cardboard, but it will be a little more durable if you make it out of metal.

My cardboard one is permanently installed in my cloning/seeding cabinet so it doesn't get much in the way of being bumped or anything like that, but if I was going to do it again I'd use light gauge sheet metal.

Personally, I usually use aluminum foil with the shiny side out, but that will probably start a big argument here. Also, wrinkles in the film, what ever it is aren't real critical except for looks.

I've used both of the types of glue that I mentioned without any problem. If the mylar doesn't feel hot fastened ot the cardboard, it shouldn't get any hotter on the metal.

Great job, man. I like what you're doing and remember, if your equipment works, the plants don't know what it looks like or what it cost you.

Ghetto or a million dollar grow area all produces the same thing, MJ. Sloppy grow techniques in a million dollar room still produce crap and excellent techniques in a ghetto room still produce good weed, assuming the genetics, nutes, and environmental conditions are the same.

Great smoking man.

 

[LEFTHAND]

Well, of the two, I think I prefer the one you made out of cardboard, but it will be a little more durable if you make it out of metal.

My cardboard one is permanently installed in my cloning/seeding cabinet so it doesn't get much in the way of being bumped or anything like that, but if I was going to do it again I'd use light gauge sheet metal.

Personally, I usually use aluminum foil with the shiny side out, but that will probably start a big argument here. Also, wrinkles in the film, what ever it is aren't real critical except for looks.

I've used both of the types of glue that I mentioned without any problem. If the mylar doesn't feel hot fastened ot the cardboard, it shouldn't get any hotter on the metal.

Great job, man. I like what you're doing and remember, if your equipment works, the plants don't know what it looks like or what it cost you.

Ghetto or a million dollar grow area all produces the same thing, MJ. Sloppy grow techniques in a million dollar room still produce crap and excellent techniques in a ghetto room still produce good weed, assuming the genetics, nutes, and environmental conditions are the same.

Great smoking man.

Yeah i didnt plan on keeping it cardboard. atleast a tin or something.. the plants may not know, but i do.. lol. everytime i look at them i will be like ahhh look at that mastercraft hood good god.. lol
i think it will hit the with light way harder then b4.. im here to same you guys money if i can an myself.. and also the obvious grow great weed.. lol
getting there.. learning learning learning...
i thank everyone who has put input and helped me on this.. it mean alot..
LH

 

[Tater]

Just a heads up but you could have achieved the same result with flat white paint.

Cheap mylar, like the kind most people buy and what "space blankets" are made from is conductive so you would need to ground it.

Cardboard can get wet and easily deform.

Cheap mylar will melt at much lower temps than the mylar used in say a spacecraft.

Cardboard can and will easily ignite.

When relying on fans to keep something cool enough to not ignite another material, what do you do if the fan fails?

Just a few little factoids, would hate to see you burn down your house, not that I don't enjoy saying I told you so (cause I do haha).

If you look around you I'm sure you can find some scrap tin or sheet metal or something. Got an old oven lying around or a traffic sign, or some old furnace ducting. All you need is some tin snips and muscle and I'm sure you can find something more suitable to build a reflector out of. And if its the wrong colour paint it white with high temp white paint. Nobody thinks it will happen to them and find it even harder to believe when it does.

 

[LEFTHAND]

Just a heads up but you could have achieved the same result with flat white paint.

Cheap mylar, like the kind most people buy and what "space blankets" are made from is conductive so you would need to ground it.

Cardboard can get wet and easily deform.

Cheap mylar will melt at much lower temps than the mylar used in say a spacecraft.

Cardboard can and will easily ignite.

When relying on fans to keep something cool enough to not ignite another material, what do you do if the fan fails?

Just a few little factoids, would hate to see you burn down your house, not that I don't enjoy saying I told you so (cause I do haha).

If you look around you I'm sure you can find some scrap tin or sheet metal or something. Got an old oven lying around or a traffic sign, or some old furnace ducting. All you need is some tin snips and muscle and I'm sure you can find something more suitable to build a reflector out of. And if its the wrong colour paint it white with high temp white paint. Nobody thinks it will happen to them and find it even harder to believe when it does.

ummmm Tater.. hate to break it to you but im not keeping it made out of cardboard..as well i have ran it with out my fans "as a test go" sitting watching.. i may be a newbie but not ********.. lol
the mylar did not burn nor melt at me running the bulb with no fans ..
when i build the final product it will be made from a sheet metal..
thanx for the concern in saftey.. i dont use space blankets.. they let light threw. ...
its made out of cardboard bcauz it was laying around and i didnt feel like wasting money on glue and sheet metal for nothing.. so i made a "prototype" lol
dont worry.. i will play safe and look both ways b4 i cross the street.. lol
that last comment wasnt to be a smart azz or anything just my kinda humour... lol
LH

 

[leafminer]

Not correct, Tater: paint reflects 90% at best, Mylar 98%. Big difference right there. With a 600W lamp, 60 watts would be just lost with a painted reflector, rather than 12 watts.

 

[Mutt]

Cheap mylar, like the kind most people buy and what "space blankets" are made from is conductive so you would need to ground it.

hate to join in tater...but those space blankets aren't mylar either.
Metallized Polyethylene terephthalate

it reflects up to 97% radiated heat....they suck for reflecting light. and they reflect way to much heat for a grow IMO.

​

 

[dirtyolsouth]

Heya Lefty...

Got any whale blubber tins layin' around up there in the Great White North? :holysheep:

Why don't you check with your local grow shop to see if they have any old dead stock reflectors... Ya never know... even if they have a piece of the metal that goes on the inside you could fashion something safe and functional to use... But i DO like saying the word MYLAR...

Peace!

 

[LEFTHAND]

Heya Lefty...

Got any whale blubber tins layin' around up there in the Great White North? :holysheep:

Why don't you check with your local grow shop to see if they have any old dead stock reflectors... Ya never know... even if they have a piece of the metal that goes on the inside you could fashion something safe and functional to use... But i DO like saying the word MYLAR...

Peace![/quote

Hey DOS nice of you to stop in.. lol you like the word MYLAR ehhh.. lol.. i have found some light gauge sheet metal.. for the right price.. just the matter of getting it home lol.. since i dont drive
bloody seizures... ahhhhhhhhhhh...
and breath.. lol... well im off to get a cup of coffee.. take care yall..
also i loose more having to go to a shop.. its an 1.5 hrs there and back to the nearest shop..
sux..
LH

 

[DonJones]

I'm not sure wheer it is but in one of the threads here on the DIY it talks about using plywood or even dimensional lumber to bend (form) light weight sheet metal.

Leafminer,

Do you know what the percentage of light reflection they get with the German Aluminum dimpled metal that the inserts for some hoods is made from?

Great smoking.

 

[Mutt]

all your doing is making a DIY break. All i would do is get a peice of sheet metal screw it to the board and bend...heating it up with a torch may make it more formable....anythings better than mylar and cardboard IMO...mylar melts very easily.
you could even dimple it yourself with a ball pean hammer

 

[LEFTHAND]

all your doing is making a DIY break. All i would do is get a peice of sheet metal screw it to the board and bend...heating it up with a torch may make it more formable....anythings better than mylar and cardboard IMO...mylar melts very easily.
you could even dimple it yourself with a ball pean hammer

Don and mutt.. that cardboard demo was a "tester".. i didnt want to take the time or spend the money on sheet metal to make a "prototype" and say nahhh.. waste of money.. which i have not to much of these days..

as to form the hood all i have to do is take a 2x4 and clamp itmake my bend and do the same to the other side.. no heat need...
i see both yer points of if the fans quit the mylar can melt.
but as far as the "cardboard" one its in the trash now.. lol i hve hte measurments i need from it to duplicate it onto sheet metal..

Neat info: i have put a 4"x4" peice of mylar in the oven at 170F and did not melt with the oven door closed..

that passes my heat test for a sheet meatal mylar "prototype"...
LH

 

[DonJones]

Mutt,

If it is aluminum, trying to heat it is risky. every metal work that I've ever talked to has said to work aluminum at room temp or only slightly above because the difference between softening it, melting it and vaporizing it is very close to the same and heating and cooling changes the characteristics much more than it does with steel based metals. Even with steel based sheet metal, applying heat to light gauge metal is likely to warp the crap out of it, and is unnecessary until you get close to over 1/8" thick, which is way heavier than we need for reflectors.

Also, have you considered how small those dimples are and how many of them there are?

Not trying to put your contribution do0wn, but I've been down those roads already in trying to figure out a good inexpensive way to manufacture hoods.

As to the cheap mylar versus NASA mylar, most of their mylar is bonded to a substrate that supports the mylar, thus making it more durable. Mylar is pretty much mylar and it reflects heat just as well if not better than visible light. The cheap versus NASA cost is very similar to the cost difference between buying a hammer at Lowes or HD or letting the government set specifications and contract for it. The hammers are nearly indistinguishable -- I've seen identical items bearing the same part and manufacturer's part number sell thorugh the civilian supply chains for well under 20 times less that procuring it through the military/governmental supply chain, and often "Procuring it through channels" cost our shop well over 100 times what we could get the same identical item for off of the local economy HERE IN THE STATES, much less overseas.

As recently as 4 years ago, the same tie down chain that I could buy for $25.00 cost the Air Force $500. Not only would the airmen sell or even give them to US, but the darn drivers would buy them for $50 instead of paying $25 through a civilian source and after you pulled the AF supply tags off of them, it was impossible to tell them apart.

God it still burns me to see our tax dollars wasted and stolen!

Getting back to the issue at hand. IF you need some advice on how to bend the and can't find it hee, just ask me and I'll try to get you some pictures and hopefully an explanation. I'll warn you though that my "shop" is a mess! I'm just finally getting my grow rooms in order a little at a time. Building and finishing as you are growing is a pain in the butt!; but if you don't have the funds to do it any other way, it sure beats not doing it at all.

Great smoking.

 

[DonJones]

LEFTHAND,

Just to humor every one, try running that same test at 500F or even better on broil. That should but the issue to rest once and for all. And if you have a self cleaning oven, leave it inside of the oven and cycle it through the cealning cycle which getws way way higer than the light will ever get. I'd try it but IF the other half caught me using her oven for something like I

wouldn't ever grow anything again. She still is complaining about me using her oven to bake paint on Triumph parts well over 35 years ago. Oh, for the innocence and courage/stupidity of youth.

Great smoking.

 

[ozzydiodude]

:stoned: and bored how about cutting the "hood out of a old washer or dryer? White enamil(?) metal that you could cut just about any shape you want.

 

[LEFTHAND]

:stoned: and bored how about cutting the "hood out of a old washer or dryer? White enamil(?) metal that you could cut just about any shape you want.

I'm looking for one.. something.. still want to cover with mylar.. why i like the way it shines lol..
all i need is a 3'x2' peice to make the hood.. knock the coners down and its done lol..

Don.. thats funny you say that because after writing my last post there i threw a chunk in at 220F 1/2hr door closed and it did nothing .. i shall throw a hunk in tomorrow morning.. i'll start it at 375F and go from there..
now i was thinking if my inline does fail i have osculating fans blowing past the light al the time so for 2 inlines and 2 osculating fans to fail is well when pigs fly in my books.. maybe one fan or 2 but 4.. is a hard pill to swallow.. but for humor i shall crank the heat up.. lol
reapot tomorrow in the AM...
LH

 

[DonJones]

Personally,

I don't think you have anything to worry about, but was just curious since ytou were already testing it. Also I thought it might put some people at ease about mylar and possibly keep someone else out of trouble.

ozzydiodue,

I think you will find that the enamel/porcelain on appliances is very brittle and probably will crack badly if you try to bend it much more than just flexing it versus putting a permanent crease into it. You might try it and let us know though since it was your idea.

Great smoking ot everyone.

 

[LEFTHAND]

Personally,

I don't think you have anything to worry about, but was just curious since ytou were already testing it. Also I thought it might put some people at ease about mylar and possibly keep someone else out of trouble.

ozzydiodue,

I think you will find that the enamel/porcelain on appliances is very brittle and probably will crack badly if you try to bend it much more than just flexing it versus putting a permanent crease into it. You might try it and let us know though since it was your idea.

Great smoking ot everyone.

I know don.. they only way i have melted the mylar so far is direct flame..
but since i have had it up to 220F and nothing mise well give her a lil more heat just to see.. .. as for the enamal on stoves and what not its a layered backed process.as well as the metal isnt prepped properly and enamal is shetty paint.. lol.. .. nicked/bent hammered it will chip and flake off..
but i dont for the paint color just the material as we all know im coving it in mylar... hehehe..
hopefully this weekend i should have it built..
LH

 

[LEFTHAND]

well i finally found some sheet metal at my cost.. i couldnt beleive what some places wanted for a 2'x3' chunk.. holy up to 35$...
once i get it totally done i will put up pics from start to end..
so far this reflector has cost me 6.50 for the sheet metal and 11.00 for the high heat glue.. not to bad...
LH

 

[DonJones]

lefthand,

What kind of metal is it? It almost looks like it might work pretty good without the mylar. Without the mylar will probably give you a softer more uniform light.

The super shiny smooth finished metals, like chrome and like mylar tend to be worse about bright and dim spots.

It looks great to me.

How about some measurements? It looks to me like it could very easily be made into an air cooled hood w/o the cool tube by adding end caps with ducting collars and putting a piece of clear window glass or even Plexiglas over the bottom.

Great smoking.

 

[LEFTHAND]

lefthand,

What kind of metal is it? It almost looks like it might work pretty good without the mylar. Without the mylar will probably give you a softer more uniform light.

The super shiny smooth finished metals, like chrome and like mylar tend to be worse about bright and dim spots.

It looks great to me.

How about some measurements? It looks to me like it could very easily be made into an air cooled hood w/o the cool tube by adding end caps with ducting collars and putting a piece of clear window glass or even Plexiglas over the bottom.

Great smoking.

hello don.. she is cheap old galvanized sheet metal.. lol... shes not all that shinny lol.. for now.. hope to have the mylar on today..
learnt alot building this one to beable to make the same thing just "store" bought.. lol i tend to be a perfectionist.. lol.. except on my spelling.. hehe

i dont think i will have to worrie about "dim" spots.. lol the hood is 3' long. by 19" wide.. and its going in my 4'x2' tent.. mylar lined walls.. shes gonna be bright..
LH