If you have a couple of hours to spare during quarantine, this DIY Neuralyzer can be a fun introductory project into the world of electronics and 3D printing. As a plus, it can make a family member or friend laugh as they see you parading around in a Men in Black costume! First, I'll explain how to make the Neuralyzer, then the costume.

Supplies

For the Neuralyzer, you will need:

1. 3V coin cell battery

2. 4 LEDs (I used 2 blue ones and 2 white ones)

3. 8" of copper wire

4. 4-pin button switch

5. Black filament

6. 2 strong magnets (9mm diameter)

7. Scrap metal

Tools:

1. Soldering Iron

2. 3D printer

3. Hot Glue Gun

Step 1: Basic Overview: Description, Design and Components

A Neuralyzer is a top-secret device used by the Men (and women) in Black that has the ability to wipe the minds of anyone who sees the flash.

This Neuralyzer consists of three parts; the top half of the Neuralyzer, the bottom half, and the circuit board, which is basically a place where you can secure the LEDs. The bottom half will contain the battery, LEDs, and button. The top half only holds the magnets used for closing it. I cut the ends off a bolt and glued it into the bottom half. The magnet latches to this, which essentially forms a sandwich between the top and bottom half. Please refer to the diagrams above for a more detailed plan.

Step 2: Print the Casing and "Circuit Board"

I designed the casing of the Neuralyzer on Tinkercad. The design comes in 3 parts for printing ease; the top half, the bottom half (where the battery goes), and the circuit board, where the LEDs will go. I printed these with supports everywhere at 50% infill with black filament. In total, the components took around 14 hours to print. These will fit on an 8" x 8" bed easily!

Here are the links to the files. To download them, simply click download, then download as a .STL file. A .STL file describes only surface geometry, and when working in conjunction with a 3D slicer, it allows a computer to communicate with the 3D printer.

Bottom Half of the Neuralyzer

Top Half of the Neuralyzer

Circuit Board

After the files are done printing, carefully remove the supports and sand the indent where the circuit board will go.

Step 3: Wiring

After printing the casings, you can start wiring up your LEDs, button, and battery. Remember to always test your circuit before soldering and gluing. LEDs have two diodes, a positive and negative side. The longer side is usually the positive end, but just to be sure, use your 3V battery to test the ends.

First, cut the copper wire into 2 4-inch pieces. Then, fold the ends of the LEDs into 90-degree angles. Lay the copper wire out on the circuit board so they make parallel lines. The copper wire on the left is now your negative side, and the wire on the right is now the positive side. Trim the LEDs and place them on top of the wire. The negative diode should be touching the negative wire, and the positive diode should be touching the positive wire.

Now, you can solder the ends of the LEDs to the wire. Make sure they are spaced evenly, so they fit snugly inside your printed circuit board. After you finish, trim the excess metal off the LEDs and place it in the circuit board. Optional: cover the wires with hot glue to ensure a secure bond.

Tip: Before soldering, score the place where the LED meets the wire. This will make it easier to find the exact placement.

Step 4: Put Everything Together

Now, hot glue the circuit board into the bottom half of the Neuralyzer. Run the negative end of the copper wire through the channel and directly into the battery holder. No detours here!

For the positive wire, leave around 3/4 of an inch and trim the rest (hold on to this, as you will need it later). Push your button into the square-shaped hole, with the button side facing out. 4-pin buttons work as gates, allowing electricity to pass through when the button is pressed. Each pin corresponds with a number 1-4. As long as you solder the wires on pins diagonal to each other (1-4, 2-3), the circuit will run when the button is pressed. If you solder the wires onto pins adjacent to each other (1-2, 3-4) electricity will pass through without the use of the button.

I soldered the wire and the button directly in the casing, but feel free to take it out if that makes it easier. After you finish soldering, take the excess wire and solder it to the other pin. Then secure (I used duct-tape) the positive end of the wire to the positive side of the battery, and rest the negative end on top. I folded the end of the negative wire so it would be firmly pressed against the battery when the top case was put on, but you can tape/solder it as well.

Soldering tips: Soldering the button was tricky for me, so here are some tips that helped me out. Tin the end of the copper wire and the pin, then simply press them together and touch the connection point with the soldering iron. The metal will melt and bind without clumping.

Step 5: Magnet Closure

Congrats, you are almost done with the Neuralyzer! The final step is the magnetic enclosure. Hot glue/epoxy the magnets to the top half of the casing, and do the same with the pieces of scrap metal in the bottom half.

Why magnets?

This magnetic enclosure allows easy access to the circuitry and components. It also allows you to replace the battery.

I hope you enjoy the finished product, and that this project inspires you to create something cool as well!