what LEDs do i need to buy to build one

I can build one but im not sure the spectrum please help?

Look for Kanna threads building your led light, if you really want to get solid info.

Good Luck

It's really very dependent on what kind of light you want. Are you looking for a light to Veg out your plants? Or do you just want really efficient flowering? In general a quality Veg spectrum diode ranges from 415nm to 500nm peaking between 430 and 450nm. Most flowering plants respond really well to a range of 640 to 700nm with a peak of 660. This was what the old fashioned led manufacturers used as a reference point for where they wanted their spectrum to be. Only within the last 3 years has the quality of diode and the proper range of nanometer been acquired for use in the industry. Remember that you can still order LED in the Kelvin color temperature range, for a wider span of light frequencies to fill out the gaps. Just because the 440nm and 660nm do hit the peaks of absorption doesn't mean that it's the only light you need. It's good to have a wide range of color available to your plants. In veg you don't have to have as much red because the plant isn't using it as much to process the phosphorus and potassium into sugars and hormones to create flowers. People get good results with home made units by kind of cheating in the sense that they copy their knowledge that they've gained from CFL's where you could only choose based on kelvin. For veg people get great results with 440nm diodes and 6500k diodes. It's a good concentration of blue with the added red and other colors you need to properly process the chemical energy stored in the plant material. In flowering I have seen many setups. Most commercial light companies are going to supply you with a light that has 440nm: 635nm:640nm:660nm: 2700k diodes at a ratio of generally 1:2:3:2. Recently on the led forum there is evidence of a swing to a simpler led light with only 660nm:2700K at a ratio of 6:9 producing great results. As Led technology ages it will get better and better until it's replaced with something more efficient. Check out 4 Kessil H350 - 600W HID Comparison. And always remember though I may be a repository of knowledge I do NOT know everything. Do tons of research and look at this link https://www.opengrow.com/topic/44537-50w-high-tech-diy-led-lamp-test/page__st__20
Sincerely,
ILove
P.S. I'm looking for someone to build me custom lights. If your results are good enough I would like to commission some custom lights. PM me or just continue the thread I'm subbed.

thanks alot ill let u know how it turns out my dad whose got 30years of electronics experience is gonna do it so i have high hopes

^^^^And if you wanna buy great DIY kits and all the equipment needed (even have solderless kits) look at rapidled.com / not cheap but quality......good luck

I posted this yesterday in another thread to clear up some confusion...

• Ok. I feel the need to clear some of the electronic side up for people...
  
  Firstly,
  
  watts = volts x amps
  Volts = current x resistance
  
  Secondly,
  
  A "3w" diode simply means its "average" nominal power consumption is approximately 3 watts total.
  ALL LEDs have a forward voltage. Expressed as vf for most 3w leds this is around 2.2~4v and they a nominal (recommended) forward current expressed as If. Usually 700ma. So.. If an led has a forward voltage of 3.2v and we run it at 700ma that would mean watts = 3.2 x 0.7 would mean 2.24w us used by that 1 led. +\- efficiency
  
  Forward voltage is how much voltage the led "eats"
  
  Thirdly,
  
  these kind of high power LEDs cannot be run by resistors alone due to resistance changes when they heat. This is why PWM (pulse width modulated) constant current drivers are used. They essentially Pulse the led on and off rapidly at the rated current, which saves power and the LEDs.
  
  Although this PWM system saves power, nothing is tuly efficient and you will have loss in the design.
  
  As a rule of thumb take the total no. Of LEDs and multiply by 3. That is the easiest way to know. Sadly in the us they only use 620-630ma drivers which is the reason why the total power consumption is lower even with inefficiencies.​

  
  
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