DIY 4x12 3500K/5000k lm561c two channel board

Nutria

Well-Known Member
For the GrowGreen boards I use 5.886" x 18" heatsinks from heatsinksusa. I have eight holes in my boards for drill tapping 3mm screws. I use self tapping screws faster. I use thermal grease to ensure heat transfer. I have found at 100w heat sink not even warm. 200w need fan for active cooling.
thanks for asking
do you think that an aluminum sheet (0.1" thickness) like this would work too?


Btw using thermal grease on such a big surface have to cost you a lot!
 

VegasWinner

Well-Known Member
I think that needs to be thicker and more area. You have to be able to dissipate 200w actively. A 5.886" x 9" can handle 50w max activiely. I would imagine you will need a c/w similar to the heatsink I use :
Extruded Aluminum Heatsink
Alloy: 6063-T6
Width: 5.886"
Fin Height: 1"
Base: .270"
C/W/3": approximately 1.75
Weight per Inch: .25

If you can calculate your c/w for the section you have and it is 1.75, you8 will be ok for 200w. I use s squeegee to apply the thermal grease and so I maximize the usage. I buy larger size than single usage containers.
 

Randomblame

Well-Known Member
do you think that an aluminum sheet (0.1" thickness) like this would work too?


Btw using thermal grease on such a big surface have to cost you a lot!

You need to add fins on the backside to increase cooling area. A few C-channels can do this.
You need ~110-120cm²/w passive and ~40-50cm² when active cooled.
 

Nutria

Well-Known Member
Thx both guys. I don't know how to calculate the thermal resistence, I'll check but if u can help me that would be cool.
Here where I live we can't find custom size heatsinks, just aluminium sheets more or less thick.
Even if I assume I would not run it more than 100-120w.
If I get an alu sheet the same size the pcb is how would you add c-channels or a fan? how would u secure these to the alu sheet? You can't use screws if there s a pcb on the other side of the sheet.

If I am going to spend 100usd for an heatsink I will stick to cobs
 

Randomblame

Well-Known Member
You can simply drill a few holes and screw them together or use thermal glue and some epoxy at the ends. But I would use a sheet 1-2" bigger as the board/strips for this reason and to increase cooling area.
You do not have to dive into the thermal laws, it's enough to calculate all the surfaces of your heatsink and make sure it's enough.
 
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Nutria

Well-Known Member
You do not have to dive into the thermal laws, it's enough to calculate all the surfaces of your heatsink and make sure it's enough.
ok for surface but is thickness important too?
If you want to use pc fans on a alu sheet how would u attach em to the sheet? thermal paste isn't enough to keep it safe.
 

Randomblame

Well-Known Member
Not as much as with COB's because the heat is more spreaded. 2-3mm should be enough as base plate and with 2mm C-channels the thickness increase partielly to 5mm.
For an additional fan you could add two small alu strips to the fins, bent the last inch on both ends by 90° and mount it to the fins with selftapping screws.
 

Moflow

Well-Known Member
Here's what I got

https://www.poweralia.com/extruded-heatsinks-bars/rg14068-1000-pw

I took measurements of the Chilled led heatsink and looked for something with a similar profile.
I would imagine that the Chilled boards might run a tad warmer than the Growgreen boards.
This heatsink might run the growgreen boards passively.
Expensive enough at about 40 quid for 18".
If anyone would like to check out the PDF on the link above and comment on its capabilities that would be great.
 

Randomblame

Well-Known Member
I've used these selfmade heatsink with 6 CXB2540 + some 430 and 660nm 10w COB's at 120w max. and completely passive. Case temps stays well below 50°C also with 30°C ambient temperature. The calculated surfaces of the whole heatsink is ~5100cm² : 110= means it is enough to remove 46,4w of pure heat passive.

LED's are around 50% efficient, so half of the power is heat. In my case that would be around 60w. It's above the calculated limit but there's always a little airflow in my chamber and together it seems enough.
Selfmade LED Heatsink, 600x350mm, used passive with 120w, T.c stays below 50°C.jpg
 

Randomblame

Well-Known Member
Here's what I got

https://www.poweralia.com/extruded-heatsinks-bars/rg14068-1000-pw

I took measurements of the Chilled led heatsink and looked for something with a similar profile.
I would imagine that the Chilled boards might run a tad warmer than the Growgreen boards.
This heatsink might run the growgreen boards passively.
Expensive enough at about 40 quid for 18".
If anyone would like to check out the PDF on the link above and comment on its capabilities that would be great.

Can not tell you much about it's max capabillities, but he should definitely go for one GGboard.
These bad boys are used to cool up-to 8 COB's per meter heatsink with only one 140mm fan on the backside.
@REALSTYLES have used them with 8 CXB3590, I believe. Also the popular 3 Vero29 kit from RapidLED seems to use this typ of heatsink, but only 24" and with a HLG-240!
Also without much calculation, I can say that this babe's will work really well.
 

Prawn Connery

Well-Known Member
I got banned from icrag due to gypsy videotaping his firing/belittling an employee for "entertainment " purposes.........actually the hammer came down on a lot of guys from that , we all came here:)



what's he been up too since prison?
Like I said, we go back a long way. I was a very active member of the old OG Shark Tank - at least in my "Prawn Connery" incarnation. I had other grow handles back then, but PC was my troll handle (hell, I had an ARMY of troll handles back then, LOL!) and, well, he was the one who seemed to strike a chord with most people, so I kept him, and here I am today, forever known as "Prawn Connery" and not one of the other dozens of handles I created over the years.

After the OG Shark Tank closed, a bunch of rebel OG members went off and built our own Shark Tank. That led to my own grow site - planetganja.com - which was the first, truly unmoderated pot site (with only rules to protect people's real identities - ie; no "outing" of real-world info that could have legal implications for growers).

We used to bash ICMag - and admittedly Gypsy as well (it was all good fun) - mercilessly, and so I was persona non grata there probably even before ICMag was born!

Then there was the POM (Plural of Mongoose) episode . . . but that's another story.

Gypsy and I still have a laugh about it to this day, but do you think I'll ever be let back on to ICMag as Prawn Connery? No fucking way. And I can't be arsed creating another sock puppet account to post there. I'd rather post somewhere like here.

If you want to know what Gypsy is up to these days, you can read about it here (hope the mods don't ind me posting the link): https://myplanetganja.com/viewtopic.php?f=13&t=11571&start=15

I don't admin or own "myplanetganja.com" - it's another spin-off of the old planetganja site - but ironically, it's one of the better sources out there for info on Gyspy and POM's legal woes.
 

VegasWinner

Well-Known Member
Here's what I got

https://www.poweralia.com/extruded-heatsinks-bars/rg14068-1000-pw

I took measurements of the Chilled led heatsink and looked for something with a similar profile.
I would imagine that the Chilled boards might run a tad warmer than the Growgreen boards.
This heatsink might run the growgreen boards passively.
Expensive enough at about 40 quid for 18".
If anyone would like to check out the PDF on the link above and comment on its capabilities that would be great.
that one works fine with active cooling at 200w and active at 100w for safety.
peace
 

VegasWinner

Well-Known Member
There must be an issue anywhere in the calculator.
The calculator say 0,14μMol/j for the far reds at 1A, so 51w can not be 73μMol/s ... it's more a tenth.
Seems the comma has slipped by one point!
This would also indicate that far red drives photosynthesis better as royal blue which is simply not true.
1,26μMol/j seems also not very efficient...
You also changed the calculator values for red and blue in your last post, which is a bit misleading. Either you write too fast or you do not sleep enough.
I had to dig into the error.
The far Red should be 1.4 micormoles, an error of a decimal place. correcting the Far Red.
thanks for pointing out their error
peace
 

Moflow

Well-Known Member
Sneak peek. Red/Blue 75w board on the left FR/UVA on the right. Limited quantity available after testing. Red channels use lpc-100-1050 driver blue and uva channels use lpc-60-1050 driver.
Looking great!
Throw up a pic or two of it lit up.
We got the latest apogee meter the other day, a group buy to keep the costs down.
I'd a quick look at it last night, nice. The cheapest we could get it was from Spokane, probably round the corner from you lol
I'll try n do a PAR map of the GrowGreen boards in a week or so as we gotta share the meter.
I believe now that my lights are probably too close to plants at 12" away so I'll know for sure shortly.
 

VegasWinner

Well-Known Member
Looking great!
Throw up a pic or two of it lit up.
We got the latest apogee meter the other day, a group buy to keep the costs down.
I'd a quick look at it last night, nice. The cheapest we could get it was from Spokane, probably round the corner from you lol
I'll try n do a PAR map of the GrowGreen boards in a week or so as we gotta share the meter.
I believe now that my lights are probably too close to plants at 12" away so I'll know for sure shortly.
Thanks. I will look forward to your PAR numbers. I thin k 100w will perform best at 12" and 200w at 24". We shall see.

I keep my lights 18" at least minimum and 30" distance for veg.
I will have pictures of he new boards by this weekend with some PAR numbers also. I expect them to perform well based on the Luminex Calculator.
 

Moflow

Well-Known Member
Thanks. I will look forward to your PAR numbers. I thin k 100w will perform best at 12" and 200w at 24". We shall see.

I keep my lights 18" at least minimum and 30" distance for veg.
I will have pictures of he new boards by this weekend with some PAR numbers also. I expect them to perform well based on the Luminex Calculator.
Yea , ive 2 boards directly over 2 plants at 150w apiece 12" away.
The plant under the board with the extra 20 watts of Epistar 410nm and 20 watts of 660nm on the corners looks slightly different to the one under just the samsngs only.
Bigger buds with samsungs only. To me anyhow. Probably light poisoning lol

Taking longer than expected to get the other 2 boards sorted but I ordered 1 x driver this afternoon
I've cut the heatsink with a hacksaw, drilled the holes for wires, the holes for hangers
and drilled n threaded the M3 board holes on one heatsink, hence one driver .
Plus the other sink has a snapped drill bit in it - oops .
I'l sort it shortly.
 

Moflow

Well-Known Member
I just need to figure out were to put the driver, on the sink or hang it remotely?
I'e a cxb on a similar profile with the driver attached to the side.
 

Randomblame

Well-Known Member
Yea , ive 2 boards directly over 2 plants at 150w apiece 12" away.
The plant under the board with the extra 20 watts of Epistar 410nm and 20 watts of 660nm on the corners looks slightly different to the one under just the samsngs only.
Bigger buds with samsungs only. To me anyhow. Probably light poisoning lol

Taking longer than expected to get the other 2 boards sorted but I ordered 1 x driver this afternoon
I've cut the heatsink with a hacksaw, drilled the holes for wires, the holes for hangers
and drilled n threaded the M3 board holes on one heatsink, hence one driver .
Plus the other sink has a snapped drill bit in it - oops .
I'l sort it shortly.

LOL! I can not even count how many M2 and M3 taps have already broken off with the cordless screwdriver. Without a drill press it is a pain in the ass to make such small holes ...
And about your driver mounting concept,
if you need the heat inside your room mount the driver on the heatsink, if it's already warm enough mount it outside.
Can it be that the plant with 410nm has smaller leaves and everything looks a little smaller? Color of the leaves should also be a bit darker, if I remember correctly, because I've also driven the combination 3500k + 420nm + 660nm.
Would be nice to see some pictures.
Find it in veg very useful, but in flower they need only a little although it has positive effects to the resin and terpene formation.

At my new lights I renounce 420nm, because I will use UV-B tubes in the future. They cover the entire blue area very well and make the 420nm LED's superfluous.
 
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Moflow

Well-Known Member
LOL! I can not even count how many M2 and M3 taps have already broken off with the cordless screwdriver. Without a drill press it is a pain in the ass to make such small holes ...
And about your driver mounting concept,
if you need the heat inside your room mount the driver on the heatsink, if it's already warm enough mount it outside.
Can it be that the plant with 410nm has smaller leaves and everything looks a little smaller? Color of the leaves should also be a bit darker, if I remember correctly, because I've also driven the combination 3500k + 420nm + 660nm.
Would be nice to see some pictures.
Find it in veg very useful, but in flower they need only a little although it has positive effects to the resin and terpene formation.

At my new lights I renounce 420nm, because I will use UV-B tubes in the future. They cover the entire blue area very well and make the 420nm LED's superfluous.
It' all about experimenting with the cheapo Epistars - to see for myself - what happeñs
I've ordered 2 of those 385nm 10 watt Epileds, couple of weeks to arrive so I'll swap out the 410nm maybe.
I must look into the reptisun type tubes with the uvb but it'll probably be after Christmas now unless I get one as a Christmas pressy.... lol
I'l see if I can get a pic or 2 later
 
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