What started as just the Neutrino Wand has turned into building a full pack for my son this Halloween. The goals were pretty simple. Replicate the movie pack as best as I could, keep it low weight, and give him some stuff to play with. Here is what I came up with…
The result is about 80% scale, around 8 pounds on the back, and completely mirrored as my son is left handed. The pack is 3D printed using a PVC backpack frame and some other odds and ends to finish it off. The lights and sounds are based off an Arduino Nano that is controlling a bunch of Neopixel LED’s and an Adafruit Audio FX Board. The entire code, models, and PC boards used can be found on github here:
Here are some pictures from the build process. First off the circuit design. The power source is actually an 11.1v lipo. The circuit design and arduino code took the most time to develop
The 3D plans for printing are based off a number of existing designs on thingiverse. The base model for the pack is from Mike O’Riley’s model with many modifications, updates, and details added. The Neutrino Wand is still based off DancinFool82’s but heavily modified to be scaled down. It’s a very nice upgrade for the Spirit of Halloween Proton Pack you can buy too and I’ve shared my modifications here
The wand was mirrored and printed. It uses PVC pipe for the handles. The clear nose section on the wand is a glitter tube you can get at Walmart or Michaels. It was sanded a lot to reduce the 3d print lines. I then used some Bondo spot putty to fill in the larger gaps, sanded, and then sprayed with Rust-Oleum Automotive Filler Primer. It was then sanded again with 400 grit sandpaper
The final model for the full pack starts to take shape…
As does the circuit design and code
Printing out the parts on my Monoprice Maker Select v2.1 printer took a good while.
I think about a week of printing. In the meantime I continued to work on the code as well as sourcing some of the tubing and other bits.
The code is starting to come alive at this point.
Next we start to trace out and cut what they call the Motherboard. This is what the backpack and straps are connected to.
I also started work on the backpack frame. This was an early prototype. I am using real alice frame straps
Filling, sanding, filling some more… Preparing for the coat of filler primer
Now fully primed and sanded we can start to see how it’s coming together. Looking pretty good!
The wand got the first coat of matte black.
More sanding and filling. It’s about to get its first coat of black.
The first coat is done and I start in on the fittings and testing decal sizes.
The wand is the first to get all of the decals.
And the switches/buttons/light covers installed
It came out better than I could have ever imagined…
The pack now has it’s final coat of black and the parts are starting to be glued in place.
The final decals, hoses, and ribbon cable are installed
Testing all of the electronics before mounting in the pack
Next came building the boards for mounting in the pack. I had the powercell, cyclotron, vent light board in the middle. The arduino/sound board in on the right, and the power converter/amp board on the left
And we get to show it all off. What a fun project and my son is beyond happy with his Proton Pack.