Fine-Tuning my DIY LED Setup

[SnotBoogie]

Hello LED forum!

So if i say so myself, i am a massive newbie when it comes to growing. But I have decided to jump in at the deep end for my second grow: Building myself a DIY stealth cab from scratch. I won't go into the boring details, but I have approximately 24"L / 18"W / 22" H to play with. Haven't put it together yet, but here is the planned specs.

Flower

Spectrums by wattage

32w 6500K 1W LED
24w 455nm blue 1W LED
20w 625nm orange 1W LED
35w 660nm red 3W LED
46w 2700k CFL


TOTAL= 157w (83w on spectrum, 32W 6500K LED, 46W 2700K CFL)


- 1x all red panel (30w)
- 4x 8 6500K / 6 blue / 5 orange (19W each)
- 2x 2700K CFL (23w each)

I won't trouble you guys with veg tent details for now. So, here are some questions! I haven't decided how many plants to do yet. Opinions on this are welcome too. I'm thinking either 4 autoflower or 2 photo plants

First. I'm worried I don't have enough ~660nm light. Do you think I need more, proportionately?

Second. What about the other way round? With those 6500Ks putting out mostly blue/yellow light (from what i understand) plus the blue leds, i'm worried I have wayyyy more blue than I need. Am I right?

Third. The plan is to have the 3W 660nm reds on their own panel, directly above the plant (I maintain an even canopy). The 4x 19W panels would be arranged as side lighting. Good idea or no? I've heard people talking about the importance of the "LED sudoku", mixing wavelengths really evenly, but i'm skeptical, to be honest. Will it matter that all the Deep Red is coming from above?

Fourth and finally! Say I want to rig a 3x LED drivers with an input voltage of 90V-240V together. I'll connect them via a a standard 220V wall socket. Do i rig them in parallel or sequence? Is either even safe? If not, how do i do it?


And breathe.... Hope you can help me dudes!

 

[SnotBoogie]

Duh, of course forgot something. I was also thinking of adding a little UV to my composition. Is this wise? and if so, how much, and which wavelength would be ideal?

 

[bassclef]

Hey snot! Based on knna's recommendation of 5R:2W:1B, in general you could add more red or warm white light and less blue. The 6500K gives you lots of blue as well. I think the amount of 660 is fine. Personally I'd ditch the 6500 since you already have blue and replace with warm whites (3500-4500k) as that gives you more "in between" spectrums like orange, yellow and green, which plants need too, just in smaller amounts. It looks like you're maxing out your space, his recommendation is also to add more white instead of blue at high light densities.

As far as arrangement of lights, I don't think it matters that much if it's easier for you to build that way. In a larger space, maybe. Ideally, yes, spread them out if you can as you want as much light coming to the plant tops as possible for an even canopy. LEDs can vary in brightness depending on bins and heatsinking. Also red/oranges LEDs tend to be less bright/efficient at similar current as they are more sensitive to heat than white/blues. So putting all reds on one panel and whites on another, the whites may be brighter and the leaves grow a little toward one side. (That has been my experience with my panel, btw, they love those warm whites!)

You would rig the drivers in parallel, I would think. Or you can plug them into the same power strip, which essentially accomplishes the same thing.

As for UV, I wouldn't mess with it for now.

 

[Highocaine]

Do i rig them in parallel or sequence? Is either even safe? If not, how do i do it?

Definitely not safe in sequence.. If the drivers somehow allowed it, you'd have triple the current. Putting current through the output of a driver probably wouldn't work.

I'm unsure about parallel on the DC end.. I wouldn't try it. Something in my electronics geek intuition says no, but my brain doesn't want to put together a reason 'cause it'll sound like bullshit.

I'd recommend just connecting their AC ends in parallel (power bar) and arranging lighting layout in a way that allows for the drivers to drive just the right amount of LEDs.

 

[SnotBoogie]

I'd recommend just connecting their AC ends in parallel (power bar) and arranging lighting layout in a way that allows for the drivers to drive just the right amount of LEDs.

Sorry H-caine, this is what i was referring to. not very clear of me. I'm planning to connect to AC in parallel, as you said. Any particular reason everyone recommends using a power bar instead of DIY-ing the parallel connections (other than coz its easier)?

The way my setup workss, I'll be using in the region of 10x 10 watt drivers. Each will drive only one colour of LED as i've heard that mixing them is bad for reliability (something to do with variable resistance as they heat up??) Having them in 10-LED strings should let me mix each panel's spectrum nice and tidily.

On bassclef's recommendation, i'm probably going to build a driver housing outside of my cab to avoid the extra heat. I've also scrapped the CFLs and replaced them with 2700k LEDs. Finally, most of the 6500k LED have been relegated to veg duty.

I'll upload some cooling porn later, just bought a job lot of heatsinks for dirt cheap

 

[SnotBoogie]

Here's my updated plan:

20w 6500K LED
30w 2700k LED
20w blue LED
20w orange LED
35w red LED




TOTAL= 125W


- 1x all red panel (35w) (3W diodes)
- 3x mixed panels - (40w each) (1W diodes)

EDIT: and the veg tent, if anyone cares:


10w 6500K LED
20w blue LED
10W 2700K LED

- 1x mixed 6500k/2700k panel (20w)
- 2x blue panels (10w each)

 

[SupraSPL]

If you can get high efficiency warm whites they will do the job of the orange LEDs more efficiently and it will simplify your design. 3000k warm whites peak at about 610nm and provide lots of orange and red along with some deep red. Cutter has Cree XT-E warm whites with an R3 bin for $3.25 each although shipping+handling is a bummer. LEDGroupBuy has warm white XT-E for $4 but they fail to specify the bin. Good luck with your build!

 

[Highocaine]

Any particular reason everyone recommends using a power bar instead of DIY-ing the parallel connections (other than coz its easier)?

Naw, just don't want to go around recommending 4-wire marette connections to users who don't know how to do it right (not implying that you don't know how, it's just that can be the kind of thing that causes a grow fire). I use terminal blocks to great effect.

something to do with variable resistance as they heat up??

Eh, I doubt it - but it's a safe bet anyway.

I'll upload some cooling porn later, just bought a job lot of heatsinks for dirt cheap

Got a link, or was it private?

 

[FranJan]

Hey SnotB. Hope you don't mind me stickin my nose in here, but there's too much blue in your flowering panel IMO. In most likelihood you're going to have very leafy buds with that setup? And no 730nm? Maybe the WWs will give you enough but you never know. Got any data sheets?

Best of Luck!

 

[SnotBoogie]

Thanks for the responses guys! The more the merrier, as far as i'm concerned. As i've said via PM, IMHO, DIY LED should be a standing topic in this forum. lets make it so!

Getting my drink on right now - in the morning i will upload pics of my heatsink el dorado and respond to the comments and critique you doods have shared. Thanks!

edit: and H-caine, sorry to disappoint but i just got lucky on ebay. As an added bonus, half the lot of "aluminium heatsinks" are actually copper

 

[Highocaine]

DIY LED should be a standing topic in this forum

Agreed. If it grows well and you can do it at home for a fraction of the cost, I'm sure many will agree.

As an added bonus, half the lot of "aluminium heatsinks" are actually copper

You lucky turd.

 

[bassclef]

If you can get high efficiency warm whites they will do the job of the orange LEDs more efficiently and it will simplify your design. 3000k warm whites peak at about 610nm and provide lots of orange and red along with some deep red. Cutter has Cree XT-E warm whites with an R3 bin for $3.25 each although shipping+handling is a bummer. LEDGroupBuy has warm white XT-E for $4 but they fail to specify the bin. Good luck with your build!

Agreed with this. The warm whites are my plants' favorites. They grow toward them just a little more during flower. I imagine a flowering panel full of warm whites would be pretty successful.

Hey SnotB. Hope you don't mind me stickin my nose in here, but there's too much blue in your flowering panel IMO. In most likelihood you're going to have very leafy buds with that setup?

Could be. Blue seems like a secondary spectrum in flower, but still necessary in small amounts. When I think about what goes into making those amazing HPS buds, it's not blue

Thanks for the responses guys! The more the merrier, as far as i'm concerned. As i've said via PM, IMHO, DIY LED should be a standing topic in this forum. lets make it so! ...

As an added bonus, half the lot of "aluminium heatsinks" are actually copper

DIY LEDs should be mandatory reading for newbie growers, especially micro growers. The more successful grows I've seen have been DIY, we just need more proof to convince people. They are so much better than dealing with CFLs, crazy efficient and cool, and they're really not that hard to build all things considered. And nice job on those copper sinks! Speaking of copper, I have this crazy dream of a grow room: Rows of overdriven LEDs mounted to copper pipes with water running through them to radiators, like a giant water-cooled computer rig.

 

[Highocaine]

I have this crazy dream of a grow room: Rows of overdriven LEDs mounted to copper pipes with water running through them to radiators, like a giant water-cooled computer rig.

I have thought this exact thought when working with my LEDs not two days ago.. get a wide enough copper pipe (or even just square/rectangular channel) and force water through it.. The LED density could be really tight, because you would need a lower square footage for the same cooling!

 

[SnotBoogie]

Hey guys! afraid I can't do pictures til later - looks like someones "borrowed" my USB cable.

Love the liquid cooling idea. I'm futureproofing my red panel, at least, by building it in a way that means i could change it up to active and actually draw air through the entire length of it (think water pipes, rather than mounted on top of the heatsink) I'll show pics of this too. Im pretty smug about it

As far as the comments of too much blue - I've switched it up a little (i.e, i added more flowering spectrum. muahaha!). Additionally, in reply to the comments that 2700k will more efficiently cover the orange part of the spectrum - to clarify, my "orange" is actually 625nm (so almost red) I've just named it as such for ease of identification while i plan out the panels. Does your advice still hold? I'm thinking that should give me a really nice spectral coverage all the way from yellow to deep red.

To the guy who mentioned Far Red coverage (sorry I've just remembered you mentioned this) To my understanding, far red is "shade" red - It's produced when red light passes through the leaves. If this is the case, I would be supplying far red in this manner already with this setup. Am i misunderstanding that? (The internet is full of bullshit ) Iff you guys would recommend me stickign some actual FR diodes in the mix, which wavelength am i looking for?

updated plan:

F CAB

20w blue LED
20w 6500K LED
40w 2700k LED
20w orange LED
35w red LED




TOTAL= 135W


- 1x all red panel (35w)
- 2x mixed panels - 6500K/2700k/blue/orange (40w each)
- 1x 2700k panel (20w)

I'll be using this 4-panel setup to light from above (the red panel), the lateral sides (the 40w panels), and the back (20w panel, which will be long and thin), ie blinding me whenever i open the door.

 

[FranJan]

Hey SnotB, without going into too much detail, FR from around 700nm-730nm helps promote root growth, gets plants to finish faster, (and with some indica gets them to finish period), assists with phytochrome production, get the Emerson effect going, gets the plants to drink a bit more, plus other positives. The amounts and ratios are open to debate, but it does promote stretch/shade avoidance so you do want some blues in there with them. You can also add it separately to your grow for other uses and benefits, but that's something else. I like one 730 to every four 660s in flowering and that's probably too much. Also, don't trust your average Chinese salesman to give you the spectrums you expect so be careful here if you're going with cheap diodes.

 

[SnotBoogie]

Hmmm, interesting, thanks man. Yeah I am going for super cheap chinese diodes for all but the 3w 660nm panel. I figure my wide array of spectrums coupled with the WWs and relatively safe bet 660nm panel, even if they arent exactly as advertised i'll still have a nice spread. They're also dirt cheap of course, so we shall see

Looking at FR diodes now. As far as positioning, would you just mix them in with the other diodes? I was thinking maybe you could mitigate the shade avoidance effects by mounting it further away from the plants perhaps. i.e more spread out, less intense FR light. What do you think? (yeah, sorry i should just go read wikipedia)

I have a couple of obvious choices for FR: LedEngin (which is what my 660nms are) BUT the ones they do are 725-740nm, which is outside of what you suggested. Alternatively, Everlight (who i've never heard of). Almost certainly will go with the Ledengin ones if i choose to include FR.

Ledengin

Everlight (also check out the lolzy factsheet haha)




Think i'll put together veg panel tomorrow for shits and giggles. not everything for the flowering cab has arrived yet.

 

[SnotBoogie]

You can also add it separately to your grow for other uses and benefits, but that's something else.

And what do you mean by this?

 

[FranJan]

^^^Here's a thread that's an example of using FR separately.
https://www.rollitup.org/led-other-lighting/554659-730nm-flower-initiator-vs-blue.html

 

[bassclef]

Check the datasheets of your whites, they may give you some far red as well.

 

[FranJan]

^^^^ Exactly, the WWs may be enough.

You could also just throw in some halogens on a separate timer and turn them on for two hours at lights on and then for two hours before lights out. Problem though is the halogens create quite a bit of heat because of the FR/IR it puts out. And it's own inefficiencies.

And SB anything LedEngin makes is fine for me . Those FRs fit the bill fine IMHO.