"cool tube" reflector advice needed.

[NOKUY]

hey guys.

Does anyone have any tips for putting a reflector on the inside of a home-made cool-tube???....what material would work best?

I realize I could put it on the outside real easy, but I think that the more times the light has to pass through the cool-tube glass that it looses lumens (I may be wrong about that).

I know they sell them like this, but I havent seen the home-made version yet.

 

[NiteTiger]

I personally just have aluminum duct tape on the inside of my tube. Not the best solution, but it dos keep light moving in the right direction.

 

[hogwild]

aluminum tape is really far from ideal, i would try to use some mylar if you can or find a way to coat the top half of the cool tube white.

 

[clowntown]

I tried that cheap way of putting aluminum tape on the top inside of my cooltube, I wouldn't recommend it to anyone. It never seemed to be a good reflector to me and eventually I just realized the light was probably just bouncing straight back at the bulb.

From http://www.icmag.com/ic/showthread.php?t=46419.

aluminum tape is really far from ideal, i would try to use some mylar if you can or find a way to coat the top half of the cool tube white.

Whatever you do, stay away from Mylar: it's very easily flammable (cut a small strip and hold it to a flame to see for yourself).

If you must: http://anomet.com/cgi-bin/online/storepro.php

 

[Bonzo]

Howdy Yukon, hey dude at my locay hydro store they sell the exact samt pitted metal they put in cool-tubes in 2 or 3 x 3 sheets, you any good with metal? just make your own. Thats my plan for a couple ideas i have rollin around in my head.

peace

bonz









>>>>>>>>>>>>>>>>>>>>Nam myoho renge kyo>>>>>>>>>>>>>>>>>>>>>>>

 

[NiteTiger]

Well, I believe I said right off the bat that it wasn't the best solution.

However, show me which solution that has been offered is better? Mylar will go up like a candle. The Anolux you linked, I can't tell if it is a metal or a plastic. If it is a plastic, what prevents it from melting in such close proximity to the bulb? (Seriously, I'm asking, as I couldn't find much info about it)

Also, out of all the suggestions made -

They ALL bounce some light right back at the bulb. Now, it's bad that that aluminum duct tape does it @ $6 a roll, but if a $35 product does it, it's somehow better?

Hell, some light gets bounced back at the bulb in ANY reflector. Still better than letting all of it go away from the plants, no? By that standard, the only proper way to go is vertical lighting.

Or am I misunderstanding you guys in some way?

 

[Ganico]

I don't know, but I was thinking maybe a section of disposable aluminum baking pan.

 

[clowntown]

This is from the link I posted but I'll quote it here:

If you can, get a sheet of reflective aluminum (preferably the textured ones used in reflectors, to reduce hot spots and spread light more evenly). But if not, you could build your own using a piece of sheet metal or something and painting it.

If possible, try to keep the reflective material INSIDE the glass to avoid what I call the "triple glass effect":



... since light intensity is lost through each pass of the glass. From the diameter of your tube, it doesn't look like you'll have space for the "V", but that design helps a bit as well in deflecting the light sideways so you don't lose some light that tries to reflect straight through the bulb.

These are some of the CoolTube designs commercially available:

It appears the AnoLux material are sheets of aluminum (or other metal), like what Bonzo was referring to. But I'm not sure...

 

[IdntknowMarlbro]

over Faq/ how to i build my own cool tube

http://www.drugs-forum.com/growfaq/1432.htm

he uses aluminum ducting. , i would use that or a piece of bended sheet meal.

 

[clowntown]

I have the Hydrofarm Cool Tube (19") which I got primarily because it was cheap and practically free shipping, for future use in trying out vertical lighting. If it cost any more than that ($59 + about $2-ish shipping costs), though, I probably wouldn't have bothered since I already have a nice AC reflector (Hydrotek SilverStar).

It came with a little detachable side-wing kit which allows for extra downward reflection, if you want, in two different configurations. Wider area coverage, and straight-down narrow coverage. I think it's kinda nice, and something I wasn't expecting as I didn't see it in the pictures and the item's detail didn't make mention of it.

The reflection mechanism is internal, and I like that although it is a bit limiting in that it's permanently riveted onto the frame that holds the Mogul socket. Nothing that can't be worked around by building your own frame using a metal corner angle, but still a bit annoying.

What I didn't like, though, was the lack of that all-important "V" that I keep referring to. To be honest I'm not sure how much of a differerence it would make in reality, but surely it must make some impact as you see that design on most modern reflectors.

It would have been fairly easy to convert one of those side wings into a "V" for mounting in the center of the reflector, but I opted not to do it because I won't be using the reflective insert for long.

I see a lot of the DIY designs using fairly small-diameter tubes, typically 4" Pyrex Bake-A-Round's. With or without the "V" (which I don't think is practical on a 4"), or even on 6" tubes, I wouldn't really recommend using a large-diameter MH bulb (such as typical 400w bulbs with ED37/BT37 glass, or larger) since it will restrict the airflow in the tubes. For now though I'm using it on my 250w MH light, running an aquarium-style T15 jacketed bulb (10000K), similar shape and diameter as most HPS bulbs. Although my ED28 glass GE bulb (4200K) can fit and still have enough space to move a decent amount of air, I'm seriously doubt it would fit comfortably with a "V" in there.

I wouldn't recommend the use of such a short tube (19" total length of Cool Tube, including aluminum ends) for a 1K bulb, as I'm sure a decent amount of light is lost at the ends as it is already. I think the glass area is barely large enough to cover a 600w bulb, but the 1K is much longer (both the arc tube and the glass) and I imagine using a longer tube (such as the 24" models) would allow more light out.

Centering the bulb, or rather the arc tube, would also help in achieving maximum light output (less light loss at the ends). I've been meaning to do a small illustrated how-to on this, but I've been having some trouble scratching up enough dough to get myself a camera. The method I used is spacing the Mogul socket farther away from the mount with a section of galvanized steel pipe, 1 1/4" ID (2" OD) and using longer nuts & bolts to mount the socket to the bar. On my Hydrotek SilverStar with a EYE Hortilux Super HPS 600w, a 3" spacer was required. I imagine a 1K HPS bulb would not require centering in that particular reflector. On my Cool Tube, I didn't need to do any centering of my 250w T15 MH bulb since the arc tube / bubble is placed near the tip of the bulb. The ED28 bulb, however, would require about a 2" spacer for optimal centering.

...

So that's kinda what you get for $60, which isn't too bad at all. I'm hoping the above write-up will give someone a few ideas on how to improve on their DIY Cool Tube design, or even commercial ones.

 

[NOKUY]

great advice guys!....I think I have a direction now.

I'm gonna look into that material tha Bonzo and Clowntown spoke of, and see what I can come up with. I won't need it to have very wide coverage, so that'll make it a bit easier. I'm putting (2) 150 HPS's in a Stealth cab (like the NGB cab., but w/ some modifications that will make it MUCH better) ...Mine is gonna have 2 seperate cool tubes and both lights will only need to cover about 3 square feet total. (you'll see a thread on the construction in about two weeks when I get it finished)

thanks again for all the info guys!!!!
-yukon

 

[Equipment Junki]

The 99.999 percent pure aluminum that was at the Anomet site (Canadian distributor) is ACTung I mean actually German Aluminum.

What you want is called Mirro.

The best stuff is Mirro "Siver" but it is expensive.

Mirro IV is the stuff the better quality reflectors that Sun Systems and Hydrofarm make the insert out of.

Sunlight dealers can get it it in 3 x 4 foot sheets (I think that is the size).

See the little Vee in the top of most reflectors?

That is called a restrike bend. Without it the light would bounce right back on the arc tube and cause the lamp to overheat.

An important consideration with the price of lamps.

You can use regular door and window silicone caulk to glue the borosilicate glass.

Don't bother to have the glass flame polished where it is cut.

This will put more stress in the glass than with out flame polishing.

Made a few of these myself.

Peace

 

[NiteTiger]

What's the proper angle for the restrike bend? I've got no objection to improving my setup as long as it doesn't cost an arm and a leg

Also, for those discussing the bend (clown, I think I see now that that is what you were referring to, I misunderstood, sorry), does the rest of the reflector have to maintain a certain curvature for it to be effective? Because as it stands now, my tape comes almost halfway down the sides of my cooltube to cut down on wasting light to the sides.

 

[Sauce]

I used a piece of aluminum. At Home Depot and other home improvement stores there are short pieces of aluminum ducting (~2') that are bent to the shape of a circle but not connected down the length. I bought one ($5) and cut a small piece off and bent it into a batwing shape and then stuck it down the inside of the cool tube. It's not ideal but it probably works better than most of the other suggestions I've seen. I'll try to get a pic up tomorrow of it.

You can kind of see some of it in this pic:

 

[evertking]

sauce, i have a cab about that same size.. and with summer coming its getting warm in there.. so i am going to build a cool tube like yours and try and put the reflector in there as well.... but how in the hell did you get it to stay in there??? also do you think a 4 inch vortex would work with that i think its around 170 cfm's and any advice on the size of passive intakes?... looks good!

 

[Sauce]

sauce, i have a cab about that same size.. and with summer coming its getting warm in there.. so i am going to build a cool tube like yours and try and put the reflector in there as well.... but how in the hell did you get it to stay in there???

The piece of metal I bought is already bent in circle but it isn't attached on the end, so you can bend it back the other way a little. Because of the tube size, it naturally just stays in there by pressure. Basically I bend it a little further when I put it in so it retains a pressure on the sides. I'd recommend using a cylindrical tube instead of the hurricane style one like I did. It will get better airflow and make adding a reflector easier.

also do you think a 4 inch vortex would work with that i think its around 170 cfm's and any advice on the size of passive intakes?... looks good!

With my new cab (not that one in pic) I use a darkroom louver (8x8") on one side and I use a 6" Vortex (449cfm) on a speed controller for venting a Lumatek 400w hps. I'd guess it pumps out about ~250cfm with the speed down to what I set it at, but it's hard to tell. Before I bought the Vortex I used a 80cfm bathroom fan to vent a 250w hps and it worked pretty well. However I've never run with that small of a fan in summer when temps are the hardest to control. I've read your passive intakes should have a 4:1 area ratio (intakeutake) but I would guess even a 2:1 would work fine. It also will help create a natural suction.

In a similar sized cab, I would guess a Vortex 4" should be able to cool a 250w or 400w even in summer. However it is kind of a dynamic situation and everyone is going to have slightly different results based on environment. As long as your intake temps (temps from room) are good you should be golden. Once the room heats up then you lose venting ability.

 

[HighonPottery]

I just took a piece of sheet metal and cut it into a strip that i bent longways in the shape of the tube. since it goes inside the tube, i made tabs for it at the ends so it can "clamp" itself into place. Since it was aluminum metal and not too reflective, i painted it white with flat hi-temp spraypaint. seems to work great for me seeing how it took a whole 10 min to make. i have plans to add an external wing to it when i have time as the light dispersion is around 180* and i want it to be less.

 

[Getawaymonkey!]

I just masked off 1/2 of the inside ,and all of the outside of a cooltube and painted the unmasked half inside with high temp ceramic white paint/w titanium...let it dry thoroughly and pealed the masking tape off..................
viola....insant reflector that can be removed easily enough with a sharp razorblade and fingernails, if necessary.

 

[sackoweed]

yukon
you can paint it they have some paint that will work either a reflective or a white. I seen someone do that before.. And was happy with it.. Thats a low budget way to go.. Just tape it up and paint it nice straight tape lines.. It would save money...peace..

sack