Introduction: What to Do With Random Motor Collections: Project 2: Spinning Lights (Model UFO)

About: Arduino and Robotics Nerd, and alumni of FIRST Robotics Team 5683 (Go R.A.V.E.!). Blinking LEDs with Arduino is still one of my favorite pastimes even after years of doing it.

So, I still have a Random Motor Collection... What am I going to do? Well, let's think. How 'bout an LED light spinner? (Not hand-held, sorry fidget spinner lovers.)

It looks kinda like a UFO, it sounds like a mix between a weed-whacker and a blender... What could be better? And it uses a recycled motor, old cardboard, and rechargeable batteries! Bonus points there!

So let's get to it, then...

Step 1: Materials

For every project, you should always make sure you have what you need.



a motor with a long shaft

2+ LEDs (any color, fast flashing RGBs are best),

a resistor (200 ohms or so),

a switch,


foil (aluminum is fine, but thin copper sheeting is best)



5v power supply,

a 6 AA battery box,

6 rechargeable AA batteries,


hot glue


2 long jumper wires

modelling wire



Soldering iron

Hot glue gun





X-acto knife

Glue stick

Multimeter (not required, but handy)

Step 2: Soldering the Motor

Nice and simple, just solder wires onto your motor.

Step 3: The Spinner Disc

Cut out a circle of cardboard about 3 inches in diameter.

Find the center of the circle and poke a hole with a pen or pencil.

Carefully cut out a circle of foil 3 inches in diameter.

Find the center, and use a compass or x-acto knife to carefully cut out a circle 1 inch in diameter from the center.

With the glue stick, glue the foil to the circle of cardboard, shiny side up, making sure to line up the edges.

Step 4: LEDs

Cut the negative terminals of an even number of LEDs, leaving 1/4 inch on each.

Place the LEDs across from each other in pairs of 2 on the circle of cardboard, with the negative terminals on the same side as the foil and the positive terminals on the opposite side.

Solder the negative terminals to the foil.

Glue the LEDs in place.

Step 5: Testing the LEDs

Make a test circuit, using a 5v power supply, a breadboard, your resistor, and two long jumper wires.

Touch the positive wire to the positive leg of an LED, and the other wire to the foil. The LED should light. Repeat for all LEDs.

Step 6: Adding the Motor

Poke the shaft of the motor through the hole on the cardboard circle, making sure that the foil is facing the motor.

Carefully hot glue the bottom (foil) side of the cardboard to the motor shaft, leaving a space at the bottom. If you are not confident with hot glue, skip this step for now.

Solder the positive terminals of the LEDs to the shaft of the motor. Use wire if needed.

Test that the LEDs work by touching the positive wire from your test circuit to the motor shaft, and ground to the foil.

Glue the cardboard circle to the motor shaft, covering the solder.

Note: The more level the disc, the better. Perfectly level is hard to achieve, but will save you some trouble later on.

Step 7: Mounting the Motor and Disc

Cut out 2 rectangles of cardboard of dimensions 1.5 by 3 inches (sides in a 1:2 ratio).

Cut out a 3 inch by 3 inch square of cardboard.

Glue the motor in between the two rectangles, centered, the top of the motor flush with the 3 inch side.

Glue the motor assembly to the center of the square.

Step 8: Making the Brushes

Cut two equal lengths of stranded core wire (3+ inches, enough to work with.)

Strip both ends of each, and splay one end of both to form a brush.

Take one wire, and glue it to the side of the motor assembly in such a way that the brush touches the foil ring at all times during a full rotation of the motor. It may be necessary to make a spring with modelling wire to achieve this. (That will depend on how level your disc is, and will require fiddling later)

Take the other wire, solder the resistor to the non-splayed end, and glue it to the motor assembly so that the brush touches the shaft of the motor at all times during a full rotation. (This will be easy unless you motor shaft is bent)

Note: My pictures from this step are kinda crappy, but if you look closely you can sort of tell what they are showing.

Step 9: Final Soldering

Find a battery box that holds 6 AA size batteries, or a 7.2+ volt power source. Solar panels defeat the point of this project as they require sunlight, which is not present in a dark room where this is likely to be used.

Also, the LEDs can operate at a voltage above their rating and still work, because the resistor limits the current flow, and the motor will use up any extra that the LEDs don't. (Up to a point. I'd start small and work my way up to an acceptable speed and brightness, and then not push it.) What you don't want is too little power, as it won't work.

See Step 3 of my previous project (found here) to get a recycled battery box.

Solder a switch to the positive terminal of the battery box/power source, and solder the wire with the resistor and a wire from the motor to the other terminal of the switch.

Solder the remaining 2 wires to the negative terminal of the power source.

Note: You will want to play with your motor to get it to spin in the right direction, so the brushes work at an optimal level.

Step 10: Time to Test It Out!

Take the project into a darkened room, turn it on, and enjoy!

Fiddle with the brushes so that they touch without interruption, it will make the colors cooler if you are using flashing RGBs like I did.

To get rid of some of the sound, put electrical grease on the brushes. This also means that you won't have to change out the foil as often due to wear. (Because yes, this is a problem with the design.)

Extra Steps to make it cooler (Which I thought of after my camera died, so no pictures)

Cut out a 3-inch circle of paper.

Cut out middle 1/2 inch circle (Exacto knife), set aside.

Cut a 1/2 inch section from the newly formed disc (Like a pie slice).

Color it in to look like a UFO.

Fold the disc so the ends touch and form a cone with it's top cut off, tape together the ends (hereafter referred to as "cone-thing").

Glue the cone-thing on top of the cardboard disc.

Cut the 1/2 inch circle to fit on top, color it in to match, and glue on top of the cone-thing.

Now your disc looks more like a UFO!

Step 11: Troubleshooting for the Non-electrically Inclined:

If it spins but the LED(s) will not turn on:

Make sure the brushes are touching the foil and the motor shaft properly.

Ensure that the LED(s) work.

Check your resistor. If it is too large a resistance, the LED(s) will appear very dim or not light up at all.

Make sure your soldering is correct, and all contacts are connected properly.

If it lights up but does not spin:

Make sure your motor works.

Ensure the LEDs are not drawing too much power (less LEDs = faster spin).

Make sure the motor is wired correctly.

If it won't do anything:

^ Do all of the above. ^

Check your switch.

Make sure everything is soldered correctly.

Check for short circuits (wires that connect power and ground with nothing in between).

Ensure your power supply works and is correctly wired.

Make sure your batteries are charged.

Step 12: Conclusion

So, you now have a mini UFO simulator! You can improve on it, make more to get rid of your RMC, add it to another project, or just let it sit there and look cool. It's up to you, really.

If you liked this Instructable, don't forget to favorite and vote!

Do you have suggestions for improvement?

Let me know in the comments below! (Hey, that rhymes!)

These are the projects by Dangerously Explosive; his life-long mission, "To boldly build what you want to build, and more."

You can find the rest of his projects here.

Make It Move Contest 2017

Participated in the
Make It Move Contest 2017