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Current time:0:00Total duration:7:19

Video transcript

all right so we're going to make a motor and similar to the one that we use in our hair dryer much simpler but similar principles are involved so we're going to take a block scrap block of wood and we're going to mark the corners line to line and we're going to just you do that so we can find the center of the block and that'll just give us a reference point we've got some copper coil here this is magnet wire and that's the same type of wire that's used inside of our motor we're going to use that to make our field windings and then we're also going to use some permanent magnets so we need to find a place that we can mount all of these different things and we need to determine how we're going to set the magnets up so we're going to make sure that the magnets are oriented so that their poles are opposing one another and also have two washers here we're going to use those washers as bearings and I think we're going to make our field windings about the size of that cap now be careful the magnets will snap together so now we're just positioning all our parts that we're going to need and trying to figure out where they'll they'll go and how close they'll need to be together of course the cap is what we're going to make our winding around so the washers that are going to support the winding need to be pretty close to the cap and the permanent magnets also need to be pretty close so we're just making our marks here so that we can position everything and it's pretty important that things are lined up fairly accurately otherwise the winding may not turn smoothly so we determined that we're going to measure off of the center point and about an inch away from the center of the square so now that we have our intersection points marked we're going to go ahead and drill our holes we've taped the drill about a half an inch up so we want the hole to go in about half an inch and we're using a 3/16 inch bit on the sides and then we'll use a eighth inch bit for our for the other sides and the other sides are going to hold our bearings so these are the bearing screws and we just happen to have some extra scrap screws so that's what these are these screws are from our four these actually came from an Ikea bed and then these are just some scrap screws we have laying around you can use any any screws or nails what's important is that the screws are lined up right and that they're the same level so that will improve the efficiency of our motor so we're just checking the level of making sure everything's lined up correctly and now we're going to take some hot glue and get our permanent magnets make sure that they are oriented so that they are attracted to one another so we want their opposite poles facing one another and so we just put some hot glue on the screw and then set the magnet in there and the main reason we did it this way is that it's really easy to change the position of the magnets if we need to and where we may need to do that so we've got a washer here and again we're just hot gluing that washer right in place in a vertical orientation and the hot glue allows for easy adjustments and so now we're going to take our bottle cap that we had talked about earlier we're going to wrap our field coil around it and we're going to go around at seven times and then once we've got the coil a fairly good length we have about three inches of wire on either side we'll loop the wire through and tie it off so that it doesn't so that it stays in a consistent loop there we go and then we'll do the other side as well we'll just loop the wire through and that just kind of holds the loop together and gives us something to connect with our washers all right now we're just going to tape the edges of the wire to keep it um together and we're just using electrical tape you can really use any kind of tape that you happen to have again this wire is insulated even though it doesn't look like it is it has a thin lacquer coating on it and so what we need to do now in order to allow a power to flow through the wire and to get it to behave like an electromagnet is we need to scrape off the lacquer coating on one side and notice how I'm rotating the coil that's important if you just have a thin strip scraped off it may not be enough so you really want to make sure the entire back side of the wire is completely scraped clean of the insulation and you can feel the difference once the insulation is completely gone it's it's a little rougher then when there's it's still there so now we found out that the magnet was a little too close and so we were able to take it off with the hot glue just pop it off and then reposition it okay so we're just making some fine-tuning adjustments with our field there and what's happening is the power flows from the battery through the washer into the coil and creates an electromagnet on one side of the coil it pushes against the the North Pole magnet on the other side it pushes against the South Pole magnet then the it causes the coil to flip over and before it does that the electricity flows out of the other end of the coil back to the batteries and then the coil flips over and then the process repeats and so what's happening is that the coil is functioning like an electromagnet pushing against our permanent magnets and rotating again and again now this this coil is is just one loop the motor and our hairdryer had had five loops and so it was called a five pole motor so now we're going to see if we can use this motor to do some work so we're going to take our washer here we're going to just Mark out some some circles in paper and we'll take some scissors and we're going to cut those those circles out I'm going to make a little tiny fan out of this paper now the motors that we made isn't super powerful so we have to make a pretty light and small fan but it does it does move and demonstrate the principles so we're just twisting each of the vanes on the fan so that they are each of the blades I should say on the fan so that they look more like a real fan and we're going to push that through the end of our coil and we just put a little bit of hot glue on that to hold it in place and then we'll give it a whirl and see if we can get the motor to actually spin and do some work for us and it's there goes so some interesting experiments you might want to try are what happens when you take one of the magnets away if you have the two on either side what happens when you take one away what happens when you rotate the magnets around in there and they're not opposite poles facing but they're similar poles facing if you have enough magnet wire you might want to try scraping all of the magnet wire clean and seeing what happens or scraping none of it and seeing what happens and does it still turn why why not you may also want to take a look at maybe doing multiple windings and seeing if that changes the performance of the motor I hope you've enjoyed it