Solar Mendocino Motor
Hello! How do you do? This is project HowToDo, my name is Konstantin and today I want to show you how I made a solar Mendocino motor. For those of you who do not know what a Mendocino motor is, it's the simplest brushless motor powered by solar panels attached to the rotor itself. Rotor is floating on kind of magnetic bearings and one side of it is leaning to the wall. I tried to make this motor almost from the beginning of this year. I watched a couple of videos - it looks very simple and easy to repeat, I bought magnets, solar panels, made a base, but it does not work, floating on magnets - yes, but not spin. Ok, I thought problem is in solar panels, bought new one - but had the same problem. So after buying completely new parts 3 times, I was disappointed and forget about the motor for a couple month. But recently I found a video where man making it from some garbage in 10 minutes, and I'm like "whaaaaat, I want to do the same". Actually later he said to me that was he's third try to making a motor. I found everything that is left, turn On the brain, and this time it's finally working and now I share it with you.
Necessary Components
Since this thing requires some precision in manufacturing, I give a list of parts and models for printing on a 3d printer in the description, when you have all the parts on hands, the assembly will not take more than half an hour and motor will work with a probability of 99%, 1% in case you messed something up. So we will need:
Solar panels 0.5V 100mA size of 53 by 18 by 2.5mm - http://ali.pub/1yk0ic OR Amazon
Magnets 12 by 4mm with a 4mm hole 7pcs - http://ali.pub/1yk02l OR Amazon
Large magnet 30mm by 10mm 1pc - http://ali.pub/1yk07g OR Amazon
26 magnets 12 by 3mm - http://ali.pub/1yk2m6 OR Amazon
About 40m of winding wire 0.2 - 0.3mm, I have 0.25mm or 30 awg - http://ali.pub/1yk3hv OR Amazon
Also we need guides for the base and for the rotor, I'm using 1/8in ( http://amzn.to/2gPnHxy ) 3/16in ( http://amzn.to/2gJo8G5 ) aluminum rods, but in case you can't find it, I leave the 3d models made in sketchup it's free and very simple program so you can easily remake a models for guides you are using. Plus, if I'm not lazy, I'll make another model without guides in the base, but anyway you have to find non magnetic rod for the rotor, it works with the ballpoint pen refills, but it's very flimsy and it's not the best option.
Assembling the Rotor
So when we have all parts, we can start an assembling. The first thing that can be done, but not necessarily, is to select solar panels by weight, I had a maximum spread of about 1 g, which affects the vibration during rotation, but in anyway it's not critical and easy to fix. Next, I solder the solar panels with pieces of wire about 5 cm in length, in pairs, + to - . Try them on the frame and twist the wires in the middle so that they stretch, solder the place of twisting. Fix prepared panels on the frame with an elastic band and glued with super glue, just a couple drops will be enough.
Winding
Pass the guide into the rotor frame and you can wind the coils, they are made in one direction and contain 110 turns, the arrows with the dot is the beginning of the winding, I wind every new turn on the other side of the guide, you can wind 10 turns and change the side, it will be easier, the wire is thick enough to wind it comfortably.
Balancing the Rotor
When the winding is finished, it is necessary to balance the rotor, I took two blades for the knife, slowly rolled the rotor on them and glued the solder pieces to the sides. I sharpen one end of the rotor guide with a file so that it has the smallest contact with the support wall.
Assembling the Base
I begin the assembly of the base, first I made a test and did not cut off the rods, just slide the printed details on rods. Install the magnets by this schematic. How to find the pole of a magnet? Very simple, you need a compass, a magnetic compass in your phone will work, just don't bring it close, knowing that the opposite poles are attracted - we mark out one magnet and find poles on the others with it. On the rotor probably have to put a bit of tape to hold the magnets.
Test
Well, in theory, it should start spinning if you shine on one side of the rotor. Interesting moment, I spend the day, trying to understanding why it's not working, even everything was perfectly assembled. The thing was that I have in my studio two 200W softboxes with energy-saving lamps it's a lot of light from them, but motor is not working with it, although I have a voltage on solar panels. I make it work from a flashlight, later from the flashlight of the phone, from sunlight (which seems to be obvious) from a table lamp, from almost any source light other than these softboxes, keep this in mind.
Finish
Ok, the only thing is left, to bring our motor to a nice look, cut off the rods, grind them, glue the magnets, cut the tape on the rotor and reassemble, I did not glue the base it's holds good without it, I only glue the support wall. Well, that's it, you can enjoy the work done. A little later, I attached the propeller to it, although it doesn't really blow but it looks funny. Also if you don't want to build it by yourself, you can buy same motors (Or on Amazon) they are pretty cheap actually. That's all I got for today, hope you like it. See you next time!
Find me on social media:
https://www.youtube.com/c/HowToDoEng
https://www.instagram.com/konsta.kogan/