Recently, one of my kids showed me a cool little motor design he found on the internet made with one AA battery, a small neodymium magnet and a little wire. It reminded me of a little motor I first built when I was a teenager. I remember making the motor from a step by step motor demonstration in a magazine or a book. It's made out of paperclips for the rotor, paperclips for the stands, and a couple of nails for the magnets. I have made a few since then and given them away as gifts to friends.
So reminiscing, I went to Instructables to see if anyone had posted how to make one. I searched "paper clip motor" and nothing. Same results with a larger search on the web! I was surprised I couldn't find it anywhere. So, here's an instructable on a "paper clip motor" for lack of a better name. I don't know who originally designed it. It's incredibly easy to make and the design is simple.
Parts you need. Very simple...
- Large paper clips
- Two 3 inch framing nails
- Some 26 or 28 gauge wire
- Brass tacks or staple gun
Tools you'll need:
- A vice comes in handy, but not necessary. You can bend your nails in other ways.
- A good set of wire strippers that can strip small gauge wire.
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Step 1: Get Your Wire
You may have some wire already, but I simply grabbed a scrap piece of Ethernet cable - aka internet cable, LAN, "4 pair", etc.
(By the way, if you've never utilized this wire for anything, try it for one of your projects some time. It's great stuff for projects. It's easy to solder and surprisingly strong if you need to use a piece as a "twisty tie")
So carefully remove the outer jacket of the cable. There is usually a small string that you can pull on to rip open the outer plastic insulation, if not, use a pocket knife to carefully remove it. Just don't cut the smaller wires inside. Inside, you'll find 4 pairs (duh!) of wire, which is a total of 8 small wires wrapped around each other. Carefully undo these and use just one pair for this project. I started with about a 10 foot piece, which was way more than enough.
If you have other small wire like 24, 26, or 28 gauge, it might work fine. You could probably even use varnish coated copper wire for really good results. In any case, you want SOLID copper wire, not stranded.
Step 2: Get Your Nails Shaped
When I've built these before, I used straight nails. This time around I wanted to try something different and bend the nails to create a more effective magnetic field that "surrounds" or wraps around the rotor.
See notes in pics.
Step 3: Shape Your Paper Clips
You need three Jumbo paper clips to shape two stands, and one rotor. Use some needle nose pliers and shape as shown. Get the rotor as even as possible. I mean, find the center of the paper clip, and bend the two ends at 90 degrees so they are exactly in the middle of the two rotor ends. You probably won't get it on your first try. That's okay, you have extra paperclips. If not, steal some more from work. ;)
Step 4: Dry Fit Your Rotor in the Stands
Use a pair of needle nose pliers to shape a little loop at the end of your stands. Try to get them the same size, shape, height. You want the rotor to sit as square and as horizontally as possible.
Then nail it down in place with some brass tacks. You could probably use a staple gun here too.
You can make some minor adjustments by bending the stands but try to have everything shaped and set as best as possible.
Test it to see if it spins freely now before you move forward.
Step 5: Dry Fit the Nails
Pre-drill some holes where the nails will be set. These need to be as close as possible to the rotor that they don't touch the rotor.
Leave a little extra room to account for the wire wrapping.
These will be the electro-magnets needed for the operation of the motor.
Check to see if the rotor still spins freely.
Step 6: Wrap the Rotor
This is tricky. You need to wrap your wire around one side of your rotor, then wrap the same way on the other side. You need to leave 2 tails which will act as a the brush to your rotor.
This is all done with ONE single, complete piece of wire.
I finished mine with tape to hold things in place. Tape is not necessary but helpful.
Step 7: Wrap the Nails and Set in Place
Now wrap your nails. I didn't count how many wraps, it really doesn't matter. You just want to wrap almost the entire nail. Leave some extra wire on the ends. Note: You need to wrap each nail with one single strand of wire.
Step 8: Wire It Up
Look at the notes for the wiring. You should have TWO leads for the battery. One positive, one negative. It doesn't matter which is which. Find out which way the rotor spins the freest, and orient the poles of the batteries accordingly. (Since this is run on DC current, you can flip the batteries around and have the motor spin the opposite direction.)
Test to see that it spins relatively freely. The two brushes of the rotors MUST come in contact with these two standing brushes in this first picture. Trim them and ever-so-slightly bend them in such a way that they don't get hung up on the brushes of the rotors. Don't trim them too short!
Step 9: Power It Up
You can put in a switch if you like. Or you can go all redneck like me and just use tape and your fingers to hold the wires in place!
NOTE: For me, while it was spinning, it did not over heat. But, a few times it got stuck while the brushes were engaged and the wires got warm. I don't recommend you allow the brushes to "engage" while the motor is not spinning. THE ENTIRE MOTOR CAN GET HOT! Including the batteries. Be careful. Don't wire this up and walk away.
Notice the tiny little sparks created whenever the brushes come in contact!
Improvements...I think I might wrap the nails with a second layer of wire.
If you try this out, let me know! I'm open for suggestions on improvements. Enjoy!