So I started to think about this since the Kickstarter campaign ended and now I did it. I wanted to have a build plate illumination in connection with the OctoPi upgrade because I monitor the status of my printers with it even from remote. I have 433MHz plugs for them too which I can control from the OctoPIs, in addition I can control them from a third device in case something goes wrong with the OctoPIs so I am able to power down the whole system in case of something goes terribly wrong, but about this maybe in another post. So in the night the room is dark and my UM2 has an illumination so why not do the same with the BigBox? Richard Horne did it though he didn't tell much details. Here are my goals: bright, dimmable illumination of the build plate no extra power supply controllable with the firmware RGB(W) was no option. This leads to extra electronics and stuff and I do not want to show the state by illumination I just want light on the build plate so see what's going on. I searched a bit and found nice small aluminium profiles on eBay where the LED strips are in an angle of 45° and which fit perfectly right over the Y axis of the motion system and not colliding with the carriages. And LED strips too. At first I tried 60 LEDs per meter but they were rather dark. I ordered some with 120 and 240 LEDs per meter and I did it with the 240. 0.5m per side are enough, I had to cut them shorter you need about 41cm per side. To keep the current low I chose 24V LED strips. They use about 800mA per meter. I connected them to the HE2 port which has a MOSFET build in so I can dim them. Then I change the firmware to use the HE2 PIN, which is PIN 6, as LED PIN. This makes it easier with the GCODE command. You use M42 to control every PIN. M42 P6 S255 would activate PIN 6 with 100%. The M42 is designed in a away that if you omit the Px part it uses the LED PIN. So the change is only for convenience. Last I added custom controls to OctoPrint on the controls page to be able to switch the LEDs on and off and set a brightness level. I fixed the profile with double tape for now. That's it, there's light!