Think ive been led astray

testiclees

Well-Known Member
I have the answer for a heatsink, hot water baseboard heater pipe. It's called fin tube. I don't know the price. The steel pipe kind probably aren't too costly. Copper would be more expensive. They look like they should actually conduct heat away better than the thick heatsinks people are using now, more surface area. Looks like just the right width for cobs. Unfortunately, it's ridiculously costly. Guess you'd have to find some used. Actually, just use thick aluminum foil and fold it into a bunch of fins. That's your cheapest bet.
You can go on ebay and search scrap heat sinks. I purchased a 31 x 12" sink weighing 29# for $70 shipped. I trimmed it on my chop saw. Right now it is passively cooling 4cxb @ 50w each with ease.

http://www.ebay.com/sch/m.html?_odkw=no+name&_ssn=southbendindustrial&_armrs=1&_osacat=0&_from=R40&_trksid=p2046732.m570.l1313.TR0.TRC0.H0.Xno+name+heat+sink.TRS0&_nkw=no+name+heat+sink&_sacat=0
 
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SaltyNuts

Well-Known Member
I suppose it would be wisest to just buy the cobs and make your own mounting. No commercial lamp is going to evenly cover a 3x3 or 4x4 square. Besides, it's more fun and satisfying to make your own stuff. I wouldn't buy commercial heat sinks though. They look overpriced. It's just aluminum. Just tig weld fins on a flat sheet yourself. Just rent a tig welder for a day or whatever. There may be something else that would work anyway. Just needs to be high surface area aluminum. Actually, you could probably use a part for an air conditioner.
a benefit of buying an anodized heatsink is the anodized surface aids with the heat radiation in an open design with no forced air, so better for passive cooling.
 

SaltyNuts

Well-Known Member
my gawd what is that, is there a V8 under there?

All you have to do to that light is this.

I have been trying to dial in my room for a while and just have had bad luck these last 3 runs, so I can't give true #s with this light, but I have it over a 3'x3' tray with a 40"x40" canopy. I have been running full strength for the last 3 runs and my Blue Lab truchean PPM stick has been reading around 800 PPMs. Yesterday I tested some of my tap water and it is at 700 PPMs, so I have been feeding them at over 2000 PPMs. For now I am using bottled water. My best yield with this light at over 2000 PPM was .55 grams per watt. So they do work, just I don't have a problem free run with them yet.
 

alesh

Well-Known Member
I suppose it would be wisest to just buy the cobs and make your own mounting. No commercial lamp is going to evenly cover a 3x3 or 4x4 square. Besides, it's more fun and satisfying to make your own stuff. I wouldn't buy commercial heat sinks though. They look overpriced. It's just aluminum. Just tig weld fins on a flat sheet yourself. Just rent a tig welder for a day or whatever. There may be something else that would work anyway. Just needs to be high surface area aluminum. Actually, you could probably use a part for an air conditioner.
I don't think you'd save any money.
I'm buying heatsinks by weight anyway - there's about $1 difference per kg when you compare HS vs standard profiles such as L or U.

In the end, you'll end up with the same heatsink as everyone else.
 

bicit

Well-Known Member
I suppose it would be wisest to just buy the cobs and make your own mounting. No commercial lamp is going to evenly cover a 3x3 or 4x4 square. Besides, it's more fun and satisfying to make your own stuff. I wouldn't buy commercial heat sinks though. They look overpriced. It's just aluminum. Just tig weld fins on a flat sheet yourself. Just rent a tig welder for a day or whatever. There may be something else that would work anyway. Just needs to be high surface area aluminum. Actually, you could probably use a part for an air conditioner.
I'm all for DIY, but not everyone knows how to run a tig with aluminum, let alone with the coordination to make it look pretty. That's pretty intense compared to the rest of the skills required for DIY lamps.
 

BobCajun

Well-Known Member
You can go on ebay and search scrap heat sinks. I purchased a 31 x 12" sink weighing 29# for $70 shipped. I trimmed it on my chop saw. Right now it is passively cooling 4cxb @ 50w each with ease.

http://www.ebay.com/sch/m.html?_odkw=no name&_ssn=southbendindustrial&_armrs=1&_osacat=0&_from=R40&_trksid=p2046732.m570.l1313.TR0.TRC0.H0.Xno name heat sink.TRS0&_nkw=no name heat sink&_sacat=0
Yeah, I guess it's best to use the official stuff. Improvising on heatsinks could lead to some lost LEDs, which would be costly.
 

BobCajun

Well-Known Member
a benefit of buying an anodized heatsink is the anodized surface aids with the heat radiation in an open design with no forced air, so better for passive cooling.
You're right. They make the commercial heatsinks with special properties I'm sure. Improvising heatsinks would probably be a bad idea.
 

BobCajun

Well-Known Member
I'm all for DIY, but not everyone knows how to run a tig with aluminum, let alone with the coordination to make it look pretty. That's pretty intense compared to the rest of the skills required for DIY lamps.
Yeah I know. That post was pretty crazy. Sometimes I don't think things through before I post em.
 

BobCajun

Well-Known Member
All you have to do to that light is this.

I have been trying to dial in my room for a while and just have had bad luck these last 3 runs, so I can't give true #s with this light, but I have it over a 3'x3' tray with a 40"x40" canopy. I have been running full strength for the last 3 runs and my Blue Lab truchean PPM stick has been reading around 800 PPMs. Yesterday I tested some of my tap water and it is at 700 PPMs, so I have been feeding them at over 2000 PPMs. For now I am using bottled water. My best yield with this light at over 2000 PPM was .55 grams per watt. So they do work, just I don't have a problem free run with them yet.
Looks like a pretty good reflector. The lamp looks a little close to the tops though. You know it's supoosed to be at least 18" right? You should be getting a lot higher yield than that. One person used a 5'x5' grow tent and got 849 grams. You should be getting at least a pound. It may be better to use a larger area with less light intensity than a small area with high intensity, as it looks in your image. A 5'x5' area would only be 16 watts/sq ft, but LEDs are at least 50% more efficient than fluorescents so that would be like at east 24 watts/sq ft f fluorescents, which is actually enough to grow plants. Anyway, maybe experiment with different areas and lamp heights and see what works best. You gotta be able to get more than .55 g/w.

If you could get a few red LEDs to put around the whte one it might also boost the yield. I saw a YouTube vid where a guy made a DIY lamp with one white array and two smaller reds, and he grew a hot pepper plant that looked quite robust. Apparently the white LEDs put out enough blue that you can add reds without also adding blues. You would get a pink light with a high red spectrum. Blue doesn't actually contibute much to plant growth, just the form that it takes, making them shorter for instance. You only need about 12-50% blue light. HPS has only a tiny amount and yet it works well for plant growth. I would say 2 watts white to 1 watt red would probably work well, though you should actually be able to use equal wattage if you could get that many reds. Should boost flowering significantly.
 
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nevergoodenuf

Well-Known Member
I have just had bad luck with meters this year. I have had to replace 2 ph pens and a blue lab trucheon (5 year warranty and no calibrating). And yes that pic was take when I was starting to doubt my light, but I was over feeding them, for 3 runs:wall:. Last night I flushed my cubes with bottled water and my runoff maxed out my ppm meter. I finally have everything sorted out, I hope.
 

BobCajun

Well-Known Member
I have just had bad luck with meters this year. I have had to replace 2 ph pens and a blue lab trucheon (5 year warranty and no calibrating). And yes that pic was take when I was starting to doubt my light, but I was over feeding them, for 3 runs:wall:. Last night I flushed my cubes with bottled water and my runoff maxed out my ppm meter. I finally have everything sorted out, I hope.
When you top up the water with tap water the salts in the tap water will gradually build up. That would be another benefit of having the light higher and maybe covering a larger area. The plants would transpire less so you wouldn't have to top up as much. Covering the top of the medium with white plastic bags around the stems would also reduce evaporation from the top and also reflect light back up to the lower leaves. What I do is line pots with white trash bags, whatever size fits best (with holes poked for drainage), and after watering fold and wrap the tops of the bags around the stems. Roots will grow right up to the top of the medium that way, because it's moist all the time, so you get more growth and more use out of your medium.

You mentioned bottle water. That actually has a fairly high dissolved salts content if it's spring water. If you could get a deionizer it would strip almost all of the salts out of tap water. If your tap water is fluoridated you would definitely benefit from the deionizer, since plants can absorb fluoride and it has negative effects and would also probably pass into the smoke when you smoked the buds. A deionizer is definitely a wise investment for any serious grower. Don't drink the deionized water as is though, since it has no salts it can actually strip minerals from your body. I would add some bits of cal/mag tablets in the bottom of water containers so it can dissolve some. Rather than calcium carbonate tablets, look for a salt form, like calcium citrate or ascorbate, so it will be more soluble. Calcium ascorbate would provide vitamin C too.

With the pH pens, they'll last lomger if you store them with the electrode in a storage solution, which you can buy bottles of where you buy the pens. Just make sure you rinse it off before using it because it contains an iodide salt.
 
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FranJan

Well-Known Member

testiclees

Well-Known Member
Yeah, I guess it's best to use the official stuff. Improvising on heatsinks could lead to some lost LEDs, which would be costly.
No. There's nothing special about a heatsink usa.It would not be an improvisation. Simply search for the part that corresponds to the needed cooling power in cm.sq.
If your OCD on the pristine-ness of the sink for aesthetics maybe but for efficiency I cant think of any reason why reclaimed sinks arent best practice for personal use. Many folks on here reuse stuff.

A heatsink with a cooling capacity similar to the salvaged part I used would cost more than double. That is nearly enough to pay for three x cxb 3590, 3500 cd.
 

BobCajun

Well-Known Member
No. There's nothing special about a heatsink usa.It would not be an improvisation. Simply search for the part that corresponds to the needed cooling power in cm.sq.
If your OCD on the pristine-ness of the sink for aesthetics maybe but for efficiency I cant think of any reason why reclaimed sinks arent best practice for personal use. Many folks on here reuse stuff.

A heatsink with a cooling capacity similar to the salvaged part I used would cost more than double. That is nearly enough to pay for three x cxb 3590, 3500 cd.
Something I thought of for heatsinks is aluminum wool. You get it in 18' rolls 4" wide 1/4" thick. Theoretically it should have great heat dispersion properties. Think of the high surface area and air penetration if you blew a fan through it. $20 a roll. Just have to figure out a good way to attach the cobs to it. I was thinking attach the cobs to a thin strip of aluminum, lay the wool along it and sandwich it with a second flat strip and clamp em together with some kind of clips or bolts, maybe aluminum rivets. Strips with holes in it would allow more air penetration and reduce aluminum costs.
 

SaltyNuts

Well-Known Member
You're right. They make the commercial heatsinks with special properties I'm sure. Improvising heatsinks would probably be a bad idea.
Well, don't get me wrong, I like the spirit of re-using and re-purposing stuff, and if you got the machinery and skills to fabricate your own components that's awesome. Maybe it's reasonable to do small scale anodizing too, I don't know. btw I also picked up a tidbit somewhere that it can be beneficial to apply a special paint to the radiative surfaces, too, in addition to the anodizing. I think that mostly applies to things like the waterproof enclosures for floodlights, not sure. But it's another thing to consider. EDIT: also anodizing makes the aluminum non-conductive electrically.
 
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BobCajun

Well-Known Member
Well, don't get me wrong, I like the spirit of re-using and re-purposing stuff, and if you got the machinery and skills to fabricate your own components that's awesome. Maybe it's reasonable to do small scale anodizing too, I don't know. btw I also picked up a tidbit somewhere that it can be beneficial to apply a special paint to the radiative surfaces, too, in addition to the anodizing. I think that mostly applies to things like the waterproof enclosures for floodlights, not sure. But it's another thing to consider. EDIT: also anodizing makes the aluminum non-conductive electrically.
You can just get your aluminum anodized at a plating shop. I'm pretty sure they do that as well as plating. Might even be able to do it at home.
 

SaltyNuts

Well-Known Member
Something I thought of for heatsinks is aluminum wool. You get it in 18' rolls 4" wide 1/4" thick. Theoretically it should have great heat dispersion properties.
I like thinking outside of the box too. The problem with steel wool is it's woolly. What we needs is a cohesive conduction path, from the chip to heatsink to radiators. The steel wool would probably act as a thermal insulator, if anything.
 

BobCajun

Well-Known Member
I like thinking outside of the box too. The problem with steel wool is it's woolly. What we needs is a cohesive conduction path, from the chip to heatsink to radiators. The steel wool would probably act as a thermal insulator, if anything.
Maybe. The heatsinks I've seen used for the DIY cob lights seem awfully thick to me. I'm surprised they radiate heat fast enough really. Guess they must work but seems like a lot of costly aluminum. What about simple aluminum foil? You could fold it into a bunch of fins, like the corrugations in cardboard. I bet that would work. You'd use the heavy dury grade. It's also the cheapest and easiest thing to get.
 
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