Pictures of your DIY lights - Post your pics!!!

littlejacob

littlejacob

Well-Known Member
B
Waiks said:
Smart way to upgrade! I still need to get 730nm into the mixed spectrum cab. Excited to see the results of added 660 and uva in there.

Did you have any changes in between your first and second cob grows? Set up, results, etc.
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Bonjour
Thanks!
I am in week 4 12/12 of my first cxb 3590 grow...4/5 weeks to go...1st/2nd week of January...it is in good way...very good with only 220w...it will be my first...more than gpw...grow!
Sometimes I wonder if there's not some little fairy creatures in my box now...or maybe cob are some kind of time travel device who accelerate plants development...I am not sure!lol!
But I have the same cheese clone in both box...3.5*3.5 cxb 3590 3500ºk 220w and 4*4 600hps super red 2100ºk...since it is under the 600 it is so slow compare to cxb...2.5 time smaller and larger internodal space, light green (same clones nutes watering...it was to be sure of the difference...if you don't do that you have a doubt in normal test...not with cxb...it is night and day! )
Have a great day ★
 
sforza

sforza

Well-Known Member
JJ43 said:
The inside work was done through the end holes and the large fan holes on the top.
I will admit that it was a big time pain, but that's just because it was a first pass effort and I wasn't really that smart about it.
Next time I would take measurements from these and then do the difficult parts outside of the vinyl. I would then slide the whole internal assembly into place and add bolts where needed.
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Cool. I didn't want to have any holes on top and I wanted to make the tube out of aluminum instead of vinyl, since I felt that vinyl would act as an insulator and aluminum would act as a bit of a heat sink. The way I did it was I took a two foot section of aluminum gutter drain tubing that I cut off an 8 foot section I bought at Home Depot. The backside of the drain tubing has a seam that is easily opened up. I made three holes in the bottom side of the tube for the CXA3095 COBs I had mounted on some copper heatsinks I had. I put a fan in each end of the tube, both fans blowing in the same direction. Then I resealed the seam and made sure it did not come loose again by putting screws through the seam and by putting zip ties around the tubes. I am running the high voltage CXA3590 COBs ( 73-77 volts?) whatever they are using three 1.2 amp drivers. The light puts out a great deal of light and the aluminum tube is barely warm to the touch. The air coming out of the tube is warm and moving along pretty fast.

Thanks for the inspiration for doing the light in tube. One of the reasons that I used the tube was that the three solid copper heatsinks I wanted to use were closed on the back, but open to the sides. So I could not mount a COB to the area where the CPU is normally mounted and have a fan blowing down through the fins of the heatsink like in a normal setup. Putting the heatsink in the tube and having the fans blow across the heatsinks seems to have worked well.
 
sforza

sforza

Well-Known Member
Growmau5 said:
@JJ43 I really like the idea of using a material that is readily available and easy to work with. I was just brainstorming an idea based on your clever use of the vinyl fence post material.

Imagine NO FANs on top of each of the alpine11s, instead we have a fan on either side of a sealed channel. One fan pushing and one fan pulling, much like an air cooled HPS setup. One could even decide to duct the hot air out of the room all together. If the heat sinks were all oriented the correct direction, i dont see why this wouldnt work, assuming the openings for the COBs were largely sealed. View attachment 3464834
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That is how I built a recent light. Only instead of using the vinyl fencepost, I used a section of aluminum gutter downspout. And instead of using the alpine heatsinks, I used some solid copper heatsinks that were open to the sides but closed on the top. I press fitted the fans in both ends and so far the two fans are keeping everything nice and cool. The light is using a little over 300 watts.
 
sforza

sforza

Well-Known Member
Meinolf said:
I also like the idea to capsule the fixture very much, because it gives a more finished look, eases the handling and helps against moisture. The fence posts are nice and cheap, too. For greenhouse lighting, the reflective surface doesn't consume too much sunlight.

But whenever you put a case around the heatsinks, it requires more effort to get rid of the heat evenly. In case of the obvious cool tube design, you would need more powerful fans to create the needed backpressure. Even then, there would be a temperature gradient between the first and the last heatsink. I am sure this would be failsafe (on moderate currents) but might add significant temp droop penalty. Also, if you don't guide the air directly through the fins, a lot of air will follow the lowest resistance, probably flowing around the heatsink.

Sure, cutting large holes in the tube will help a lot, but denies the system prerequisites of a very clean look and moisture protection, in my opinion. This is criticism on a high level, of course. After all, your light pole is still outstanding. :clap:
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Perhaps that is true in theory, but in practice, two small fans used in the push pull configuration put plenty of air over the heatsinks even though the heatsinks do not fill up the entire tube and there is space between the top of the heatsink and the bottom of the tube for the air to bypass the fins of the heatsink. Also there is no temperature gradient between the three COBs that I have mounted in an aluminum downspout tube. I determined this my putting my well calibrated fingers on the aluminum around the COBs and found all three to be running nice and cool.

That is why it is always better to conduct actual experiments and find out the results rather than theorize what might or might not happen.
 
sforza

sforza

Well-Known Member
bicit said:
I've been thinking about building a 'hood' for some heatsink usa profiles. The English language is failing me this morning, bare with me. On the most basic level I was thinking of getting some thin aluminum sheet for this task. Bending it over the heatsink to create a 'mound' over the top of the fins and riveting the sheet to the outer fins of the heatsink. Then make the end plates by getting more aluminum, cutting the appropriate sized hole and using a dryer vent take-off flange. Then attach it too the hood using a combination of brackets and rivets with silicon and duct tap to seal any leaks.

It wouldn't matter if the airflow passes directly through the fins. Better, but not mandatory IMO.
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I think that what you are describing is called a shroud. I just built a light using a flat 12"x12" copper plate upon which I mounted five CXB3590 COBs. On the backside of the copper plate, I used thermal epoxy adhesive to glue low profile solid copper heatsinks above the COBs. I mounted one large 120 MM fan on the back of the light to cool the heatsinks. I was concerned that not enough air was going to flow over the fins of the heatsinks to keep the COBs cool, so I was considering using light copper foil to build a shroud over the heatsinks and around the outer diameter of the fan, so that the all the air would be forced through the heatsink fans. It turned out that when I tested it last night that the light stayed nice and cool, so I will not have to build a shroud to direct air flow. I am running all five COBs off of one Meanwell 185 .5 amp driver, so perhaps it stays cool since I am driving the COBs softly. I am tempted to add four more CXB3590 COBs to the copper plate, since there is room for them and the light is running cool, but I think it will be better for light distribution to mount the five CXB3590 COBs that I have sitting in the garage on some different lights. I am thinking of running two of them off of one of the several Meanwell 120 1 amp drivers I have in the garage.

I tried using the thermal adhesive to attach heatsinks to an aluminum plate on an earlier light that I built. I was told that it would not work, but in fact, it worked like a champ. The lights heat up the plate and the heatsinks cool the plate. I can tell by touching the plate around the COBs that the COBs are running just barely warm. The center light of the five COBs on the aluminum version is a two hundred watt version. It has a adjuster that varies the amount of watts from zero to 220 watts. If I crank up the adjuster up all the way, the plate will get very warm, to the point to where you can touch the plate and keep your fingers on the plate, but it is uncomfortable to do so. I have the wattage on that light turned down to 160 watts now, and it just stays warm. Since it is in the middle of the plate and has a higher wattage, it does get a little warmer than the four lights in the four corners. BTW, I determined the amount of watts pulled by the center light by using a kill a watt meter. I found that when I turned the controller knob one full turn, the light used 100 watts and if I gave it one more full turn, it was 160 watts. I used a paint stick to use mark the knob and the starting point, so I can dial in the 100 or 160 watts, as desired.
 
P

PurpleBuz

Well-Known Member
pictures please ? love to see the copper plate light. pretty please ?


sforza said:
I think that what you are describing is called a shroud. I just built a light using a flat 12"x12" copper plate upon which I mounted five CXB3590 COBs. On the backside of the copper plate, I used thermal epoxy adhesive to glue low profile solid copper heatsinks above the COBs. I mounted one large 120 MM fan on the back of the light to cool the heatsinks. I was concerned that not enough air was going to flow over the fins of the heatsinks to keep the COBs cool, so I was considering using light copper foil to build a shroud over the heatsinks and around the outer diameter of the fan, so that the all the air would be forced through the heatsink fans. It turned out that when I tested it last night that the light stayed nice and cool, so I will not have to build a shroud to direct air flow. I am running all five COBs off of one Meanwell 185 .5 amp driver, so perhaps it stays cool since I am driving the COBs softly. I am tempted to add four more CXB3590 COBs to the copper plate, since there is room for them and the light is running cool, but I think it will be better for light distribution to mount the five CXB3590 COBs that I have sitting in the garage on some different lights. I am thinking of running two of them off of one of the several Meanwell 120 1 amp drivers I have in the garage.

I tried using the thermal adhesive to attach heatsinks to an aluminum plate on an earlier light that I built. I was told that it would not work, but in fact, it worked like a champ. The lights heat up the plate and the heatsinks cool the plate. I can tell by touching the plate around the COBs that the COBs are running just barely warm. The center light of the five COBs on the aluminum version is a two hundred watt version. It has a adjuster that varies the amount of watts from zero to 220 watts. If I crank up the adjuster up all the way, the plate will get very warm, to the point to where you can touch the plate and keep your fingers on the plate, but it is uncomfortable to do so. I have the wattage on that light turned down to 160 watts now, and it just stays warm. Since it is in the middle of the plate and has a higher wattage, it does get a little warmer than the four lights in the four corners. BTW, I determined the amount of watts pulled by the center light by using a kill a watt meter. I found that when I turned the controller knob one full turn, the light used 100 watts and if I gave it one more full turn, it was 160 watts. I used a paint stick to use mark the knob and the starting point, so I can dial in the 100 or 160 watts, as desired.
Click to expand...
 
littlejacob

littlejacob

Well-Known Member
sforza said:
I think that what you are describing is called a shroud. I just built a light using a flat 12"x12" copper plate upon which I mounted five CXB3590 COBs. On the backside of the copper plate, I used thermal epoxy adhesive to glue low profile solid copper heatsinks above the COBs. I mounted one large 120 MM fan on the back of the light to cool the heatsinks. I was concerned that not enough air was going to flow over the fins of the heatsinks to keep the COBs cool, so I was considering using light copper foil to build a shroud over the heatsinks and around the outer diameter of the fan, so that the all the air would be forced through the heatsink fans. It turned out that when I tested it last night that the light stayed nice and cool, so I will not have to build a shroud to direct air flow. I am running all five COBs off of one Meanwell 185 .5 amp driver, so perhaps it stays cool since I am driving the COBs softly. I am tempted to add four more CXB3590 COBs to the copper plate, since there is room for them and the light is running cool, but I think it will be better for light distribution to mount the five CXB3590 COBs that I have sitting in the garage on some different lights. I am thinking of running two of them off of one of the several Meanwell 120 1 amp drivers I have in the garage.

I tried using the thermal adhesive to attach heatsinks to an aluminum plate on an earlier light that I built. I was told that it would not work, but in fact, it worked like a champ. The lights heat up the plate and the heatsinks cool the plate. I can tell by touching the plate around the COBs that the COBs are running just barely warm. The center light of the five COBs on the aluminum version is a two hundred watt version. It has a adjuster that varies the amount of watts from zero to 220 watts. If I crank up the adjuster up all the way, the plate will get very warm, to the point to where you can touch the plate and keep your fingers on the plate, but it is uncomfortable to do so. I have the wattage on that light turned down to 160 watts now, and it just stays warm. Since it is in the middle of the plate and has a higher wattage, it does get a little warmer than the four lights in the four corners. BTW, I determined the amount of watts pulled by the center light by using a kill a watt meter. I found that when I turned the controller knob one full turn, the light used 100 watts and if I gave it one more full turn, it was 160 watts. I used a paint stick to use mark the knob and the starting point, so I can dial in the 100 or 160 watts, as desired.
Click to expand...
Bonjour
If you buy cxb 3590 3500ºk 36V cd you should think about individual hs to get a perfect light spread...your cxa's can light a 1.5x1.5 area @1050/1400mA about the size of your hs...so why put all your light source in an area that only one can light!???
If you will have 4 x 600hps what will you do?...put the 4 close to each others or cut your room in 4 piece and place one at each center?
Some guys wonder why their leaves bleach?...too many powerful light cones crossing in the middle of the room and weak amount of photon on the sides...if you cut your box by the number of cob you have and put one in the center of each piece you won't regret it!
CU
 
littlejacob

littlejacob

Well-Known Member
Bonjour
It is really clean job...look like a commercial panel...some spanish should hire your skills!...lol...they sell some who looks more diy...lol!
I really have to think about casing my lights...looks more solid...professionnel!
I have access to all.sort of aluminum sheet or inox...I guess just a u shape piece of alu put on my hs to hide the fan and wires will be nice with a nice painting!
Have a great day ★
 
pop22

pop22

Well-Known Member
Why not mount a 4" vent fan directly to the hood? would eliminate the need for heatsink fans in an enclosed hood. with a speed control you could keep it fairly quiet with a speed control.


Growmau5 said:
right on Stephen! thanks for the advice. I could pull out the TIG and weld it all together for an extra 2200 sq/in of surface area. great idea.
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pop22

pop22

Well-Known Member
If your using enough thermal paste to make a "vacuum seal", your using WAY too much. Proper application of the paste is to put on as thing a flim as you can. As part of my business, I use to build high end gaming computers. I've had discussions with the makers of Artic Silver on this. You should just barely be able to tell the is tm on the surfaces. The purpose of the TM is to fill the pits and scratches on the surface of the heatsink and of the LED, etc. and increase the contact area by doing so. Using more can actually increase the junction temp as TM is not nearly good at dissipating heat as the metals of the heatsink/ COB/LED backing is. If you want to "glue" the LED to the heatsink, use thermal adhesive. And yes it can be removed. You place the assembly in a freezer for a couple hours. Use a putty knife and place it at the junction. Tap the handle with something lightly and the adhesive will break off easily. We salvaged many user video cards that way!


Waiks said:
KAPTON FOREVER!!!!

I check it often. Hasn't come loose one bit. The paste made a nice vacuum seal, and the tape is double enforced. If anything, I'll tape it up some more after this run for reassurance.
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alesh

alesh

Well-Known Member
pop22 said:
If your using enough thermal paste to make a "vacuum seal", your using WAY too much. Proper application of the paste is to put on as thing a flim as you can. As part of my business, I use to build high end gaming computers. I've had discussions with the makers of Artic Silver on this. You should just barely be able to tell the is tm on the surfaces. The purpose of the TM is to fill the pits and scratches on the surface of the heatsink and of the LED, etc. and increase the contact area by doing so. Using more can actually increase the junction temp as TM is not nearly good at dissipating heat as the metals of the heatsink/ COB/LED backing is. If you want to "glue" the LED to the heatsink, use thermal adhesive. And yes it can be removed. You place the assembly in a freezer for a couple hours. Use a putty knife and place it at the junction. Tap the handle with something lightly and the adhesive will break off easily. We salvaged many user video cards that way!
Click to expand...
I've never tried it but I'd say it could be more complicated with some COBs (Cree) as they're ceramic and quite fragile.
 
Stephenj37826

Stephenj37826

Well-Known Member
pop22 said:
Why not mount a 4" vent fan directly to the hood? would eliminate the need for heatsink fans in an enclosed hood. with a speed control you could keep it fairly quiet with a speed control.
Click to expand...
My first design I used a 6 inch booster fan inside the duct itself. I decided it took away to much from system efficiency. My cxb-8 and maximizer are passive/aircooled hybrid. It takes very little airfow. 1 6" fan will cool 8 easily
 
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