vakits 5mm LED Cross Enclosure

I purchased a couple of blank LED cross PCBs at a Hamfest a couple of years ago with the intention of installing them in my truck as assisted brake lights, but being lazy... that never happened.

Fast-forward to 2017 and I have a new 3D printer... aka a new toy. What a perfect time to do something with these crosses. The cross is designed so that the PCB sits down into the cross and a thin backplate snaps down on top of it. When powered up, the LED are clearly visible through the thin front layer.

You can get the PCB kit for this directly from the company here - http://vakits.com/led-crucifix...

OK... this needs to be printed with the following settings to be printed correctly:

Layer Height: 0.1mm

Wall Thickness: 0.5mm

Wall Line Count: 1

Top Thickness: 0.8mm

Top Layers: 8

Bottom Thickness: 0.8mm

Bottom Layers: 8

Infill: 60%

Post-Printing

Once assembled, you can either solder the wires directly to the board or, if you are feeling adventurous, you can make the cross removable like I did. The metal strips are aluminum duct tape - as in the kind used for heating/AC duct work, not the kind out of which you make wallets. The wires are attached to the the tape strips using two-part conductive epoxy. This way, to turn off the LEDs, simply pull the cross out of the base.

The LEDs on this board are wired in parallel. The power requirements and current dropping resistor(s) will depend on the LEDs you use. My LEDs are 3.2-3.8v, 30mA continuous blue LEDs. To power this from a standard USB port, I have in series with the positive lead of the USB connector two 100Ω 1/4 watt resistors connected in parallel (to get 50Ω at 1/2 watt to handle the current needed by 12 LEDs each pulling .03 amps).