Fine-Tuning my DIY LED Setup

You worked with those models before (in any colour)? I'm waiting on mine at the moment, dreading the soldering job im gonna have as they arent on stars

^^^I've only worked on SMDs and repaired or modded a few of my panels. I started planning a panel but I don't have the patience and some of the tools on hand. I'll just wait to see what Area51 puts out next before I go down any more LED paths. Ultimately I'm just too lazy to build one really .

LedEngin has a solid rep for making excellent horti diodes. Osram too, especially 630nm.

We have many sucessful LED grows without far red supplementation but I have not tried adding it so I am open to learning. Halogen might make more sense than LED in this case. Assuming the minimum numbers and the lowest bin, the far red LEDEngin diodes available are approx 13% efficient at 700ma @50c about $4 ea.



Warm white LEDs do provide some output from 700nm to 750nm, especially the 2700k.




Regarding cheap chinese leds if you have not already ordered them I would advise against it. The bins and true output are not specified so I estimate the radiometric efficiency is 15% which is lower than fluorescent. Assuming minimum numbers, even the LEDEngin deep red comes in at 23.7% efficient at 700mA @ 50c. And of course not cheap at $7-$8 each.

Using top bin LEDs your lamp can average above 40% so you need many fewer LEDs, heatsinks and drivers to get the same job done which may ultimately be cheaper. Luckily for us the aquarium guys have been buying reels and specify the bins that they sell. One impressive example, the Luxeon ES deep red EX6 bin is available for $3.40 mounted on a star from Steve's LEDs. Assuming minimum numbers it is approx 38.4% efficient at 700mA @ 50c. Cutter and LEDGroupbuy also specify bins and offer top bins cheaply. That is what got me back into DIY LED after a few years off.

And guys let's not forget that mounting them on a star is really easy! The iron plate method worked like a charm for me ... you put a iron up side down firmly secured... switch it on to full power or just slightly less if you have a powerful one.

Solder paste is going to melt pretty quick and the chip gets attached in place on its own... it's that easy!

Is the benefit of soldering them really dramatic compared to just gluing them? the ones i've seen suggest either is suitable. Kinda annoying that the ledengin diodes are tiny and practically require them (as opposed to bassclef's method of thermal pad + kapton tape, lol)

Supra, your comment tipped me over the edge on splurging on some moar ledengin modules. the current lineup:

28x Ledengin 660nm (~3W) split over 3 panels, mixed with
8x Ledengin 460nm (3W)
4x Ledengin 740nm (3W)
40x no-name chinese warm whites (1W) over 2 panels

I'll see how this goes and maybe reuse the heatsinks from the WWs at a later date.

@Snot

Gluing, like.. Gluing their heatsink pad (bottom) to the star instead of soldering?
Only problem that I can see is that the glue's thermal resistance might be a bit more than the solder's.

Couple of ideas, based on using HOT5 aquarium bulbs to approximate actinic leds (FYI I also have an LED tent):

Some of my strains do not like 660, at least when it is combined with UVL Red Life (think WW) in a 3:1. Leaves clawed and curled, but new leaves are normal since removing it ~ 3 weeks ago. If anything, put 660 on a separate circuit just in case.

Now if you are not using similar led spectrums to the Red Life (again, think WW), then 660s may be fine say with CW, but probably need some complimentary 350-400 & 700+ which a Wave Point Coral Wave provides

You only want ~ 15-20% blues. 6500s alone will provide that, but so will NW, or WWs

What's your theory as to the cause of this? Logic points towards oversaturation around 660nm but this seems unlikely to my newbie brain? Have you eliminated other possibilities (low quality diodes putting out lots of far red for eaxmple, or something like that?) It seems very strange to me that you have multiple strains that all "dislike" chlorophyll A. Each of the panels will be on diff circuits though, so i can experiment.

H-Caine, that was my thoughts too, but i'm guessing the difference in thermal efficiency is large for jubiare to bother reflowing all his LEDs..