I recently purchased a Monoprice Mini Delta 3D printer, and I was immediately impressed with how low the barrier to entry has become for high-quality home 3D printing. I plugged it in, and it instantly produced a flawless Baymax from Big Hero 6 that came preloaded on the SD card. However, after a few prints, I recognized one of its few downfalls: there was no build plate lighting, let alone an RGB light show. But that’s an easy fix. With a true maker spirit and a month to wait for eBay shipments, I added a light show to this lil’ machine. Described below are my process and parts list.

Parts List

  1. For the main lights, I used individually addressable WS2812 RGB LEDs from eBay. A similar product can also be purchased from Adafruit. I used three, one for each side of the Mini Delta triangle. Because these LEDs are individually addressable, they are perfect for a fun rainbow light show.
  2. In addition, I used an Arduino Pro Mini as the LED controller. I purchased mine from SparkFun, but any Pro Mini should do the trick.
  3. Miscellaneous
    1. Fasteners (M3 Screws)
    2. Protoboard, push button switch, stranded wire, 10k pull-up resistor
    3. 5v power source (phone charger)

Build Process

To attached the LEDs, I designed a LED bracket on Autodesk Inventor.

I printed three of these brackets to go on each side of 3D printer: the STL can be downloaded here.

The bracket screws to the extruded channel on the 3D printer with a modified M3 button head screw. On the underside of the top extruded channel (on all 3 sides) there is a pocket, perfect for a screw head. I took a cutting wheel on a Dremel tool and cut the screw head into a bar shape. The M3 Screw fits up into to the channel, rotates, and “locks” whenever the nut on the bottom is tightened. I used this approach because it does not modify the printer chassis at all, while producing a very solid mounting bracket. After mounting the 3D printed bracket, I used a small, coarse-threaded plastic screw to attach the LED light bar to the bracket.

LED Wiring Harness

The wiring on this project is relatively straightforward. The three LED light strips are just daisy chained together, connecting DOUT and DIN from each strip to the next.

Arduino Programming:

To drive the LEDs I used a 5V Arduino Pro Mini to power the LEDs and feed the DIN/DOUT. You can download all of my source code here. I added a button to the Arduino with a pull-up resistor that switches the light sequence from rainbow to solid colors. As you can see in the image above, I housed the Arduino in a small 3D printed box on the chassis of the printer. I attached it with a short piece of double-stick foam tape.

Final Product: