Jump to content

RGBW diy LED light

Recommended Posts


The problem: I created a DIY led for my pico with 2xRB and 1xCW cree leds on the 20mm star boards. The leds worked fine but they created a disco ball effect that I really didn't care for. To make things worse I'm using a glass top to reduce evaporation on my pico and the condensation was acting like lenses to make the problem more pronounced. You can see the individual light beams in the  top of the picture.


I originally had the leds spaced to give more coverage but tried to bunch them as close as possible to eliminate the effect. It helped but didn't get rid of it. So i was looking through ebay and noticed there are Cree XM-L RGBW leds. All the emitters are in one package with one integrated lens. I figured it was worth a shot and ordered 5 to try out. If I still can't stand the effect I'll have to try something else... 


The plan: Wire up 4 channels of LDD 700's for each color. Drive the LDD with an arduino I'm already using for the current light. I'll remote mount the drivers and Arduino to make it more sightly and use a large scrap heatsink to cool the LED's. I'll thermocouple up the LED's to see if I can get away without a fan, but have one ready if that doesn't work. 


Share this post

Link to post

Got all the parts in and started the build. Today I was able to stick all the RGBW leds to the heatsink (HS) and get them wired together. Still need to tack on the +/- supply leads but got all the inter wiring done. 


I mounted the leds to the HS with double sided thermal tape. We'll see if it is up to the task or I may switch to screws/thermal paste. With the led's secured to the HS I was able to get the proper length on the wires. With all that thermal mass, soldering the wires down would have been an exercise in futility/frustration. At work we have a hot air board heater that would have helped but I was doing the work at home. I made a makeshift heater by just placing some tea lights under the heatsink to pre-heat it. Made tacking on the wires way way easier.

Next step is to wire the LDD drivers and run those. Still trying to decide if I want the additional Royal blue LEDs with the RGBW but not sure where I can fit them in. It is a little crowded with the wiring



Share this post

Link to post

This will solve the disco effect just like Steve's anti disco Luxeon Rebels.


While I'm sensitive to disco and hate even a tiny bit of it the problem with using LEDs like this is the green and red channels are barely used. I've found if I keep my individual stars a millimeter apart and use the 60 degree optics from Rapid LED 90% of disco is gone. It's there...but you really have to look for it.


You can get DJ PARs from amazon that do the exact same thing and are a lot cheaper.



I also keep my tanks covered, and the glass / water drop issue is annoying. I've thought about tilting the glass so condensation just runs off, but that will be tricky getting a seal and finding a material that's water proof and can be cut to such a precise angle.

Share this post

Link to post

The frosted diffuser was going to be plan... E? Not sure how many iterations I've gone through already😆 And yes there Red and Green channels won't be running on at their max so they have increased capacity but that doesn't really bother me as much as getting rid of the disco while still having the shimmer!


I was able to do final assembly of all the electronic components and do some test runs.  It works well and I'm not getting any disco that I can tell and the tank is now more evenly lit since I was able to space the LEDs more. 


I'm working on color mixing now. main part of the day will probably be as follows

Red: 5

Green: 5

Blue: 255

White: 125


Once I figure out how I'll have them run, I'll update with the code. 


I didn't take too many pictures as I was trying to get it all together. Here is one where you can see I didn't double check the PWM wires were correctly connected. The Green PWM wire goes to the Red channel 😣. I can "Fix" that in software so not a deal breaker.  


  • Like 1

Share this post

Link to post

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

  • Recommended Discussions

  • Create New...