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Install on/off switches

Created by Karl Wendt.

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Video transcript

Now we're going to install our on-off switch and the switch that will control our LEDs. So we're going to put two about half dime sized blobs of hot glue down on the back of the bot. And remember, you want to make sure that the hot glue does not interfere with the sliding of the switch or with the contacts on the back. So when you push the switch down, just make sure you don't get hot glue in the switch, otherwise it won't work. So once those are in place, the hot glue actually dries fairly quickly on the metal surface, because it helps to conduct heat away from the glue. So once those are in place, we can begin to connect our motors, which we'll turn on and off with the switch. So the first wire that we're going to connect will be to connect the two motors together. This will help to complete the circuit. And so what we're going to do is we have a wire that's about the right length. It's about two and a half, three inches long, and we're stripping off a good 3/4 of an inch of one side of that wire. And the reason why we're stripping off so much insulation is that we're going to need to connect another wire to that wire later. So then on the other side we'll only take off about a quarter of an inch. So this is the side that has a little bit more than a quarter, maybe 3/8 of an inch there. And so again, we're going to loop that through the brass contact. And we want to make sure that it touches the brass and connects with it and it as broadly as possible so that it is very firmly conducting the electricity. And so it's tricky. You got to spend a little bit of time with it, but it will work. So what I usually do is I'll run the wire through it in a loop and then I'll run the wire to the other side and connect, again, thread the longer side of the wire through the motor. And that extra wire we're going to need to make another connection. So again, I'm looking the wire around the brass contact there so we can get as much of the wire in contact with the brass as possible. And it helps to take that needle nose pliers and squeeze it against the wire on the motors. And one thing I will say is those brass contacts are very small and thin, and they can break easily. So you have to be careful with how you crimp the wire onto the brass contact there. OK, so now we've taken a piece of yellow wire and it's about two inches long, and we've stripped the ends and put a loop in the end. And we're going to crimp that end onto our switch. So it's not as easy to build the bought this way as it would be if we were using solder, because clearly solder's conductive and it basically acts as a glue and also conducts electricity. But the glue we're using, the hot glue doesn't conduct electricity, so it's really important that our wire connections are sound. And so you may need to adjust several times to get the wire crimped in such a way that it's going to hold tightly to the connection on the switch. And so mine's coming loose, so I'm going to go ahead and put it back again and see if I can't get it held tightly in place with the needle nose pliers. And you can bend the connections up to give you a little bit more of something to grip onto there, bend the terminals, I should say. OK, so now I'm going to run the other side of the yellow wire to the exposed portion of the green wire that we just connected to the motors. So I'm going to put it in there I'm going to twist it around just like we did when we connected the LEDs or we joined the negative wire on our switches. So we're going to just twist this around. Again, we want to make sure that that twisting happens multiple times so we have a good, solid connection. And there we go. One other note is that we want to make sure that the yellow wire doesn't touch the other terminal on the switch, otherwise it will always be on and we won't be able to turn the bot on and off. So now that we've tested our motors, we can go ahead and hot glue over the wire connections to make sure they're all connected there. And we've tested our blue wires and so we're going to go ahead and hot glue over those connections. And that will help to hold the wire in place and it will help to insulate it as well. OK, so now what we need to do is we need to connect the other wire to our switch that we just wired to the other yellow wire. So the way the switch works is this is actually a three connection switch. So it's a single pole double throw switch. And it's a single pull double throw sliding switch as opposed to a single pole level throw lever switch, which we have at the front of the bot. So we only need two of these connections. We don't need three of them. And it doesn't matter. You can choose two on one side or two on the other, but you have to choose two that are next to each other in order for the switch to work. So since we don't need this connection here, this pin here, we're just bending it out of the way. This pin won't be useful because all we want to do is open and close the circuit. We don't want to switch between it two different circuits. So the next thing we're going to do is we're going to take about the rest of our yellow wire. We're going to strip off, again, about 3/8 of an inch, 3/8 to 1/4 of an inch of insulation. And once we've got that pulled off-- there we go-- we'll create a loop in it. And we'll link that loop to the exposed terminal that is on our switch, which is the terminal in the middle of the switch. So from looking at the top, we have one on the left side and then we're going to connect one wire to the middle of the switch. So we've got our wire already cut and stripped and our loop put into it. We're just crimping it onto that center terminal there. And we're going to squeeze that tightly against the center terminal with our needle nose pliers. So to test that connection, we're running that wire back to the batteries. And you can hear them running. So now we're going to go ahead and hot glue that connection in place now that we know that it works. Again basically, what this switch is doing is it's allowing us to convert our batteries, which are wired in series, which double the voltage to parallel. And that allows us to double the capacity and run the motors at a little bit of a slower speed. So once that hot glue has turned that milky color and has cooled down, we will connect the wire to the battery in the back. So the hot glue's cool. We're going to go and pop our battery out of the holder. There's a little hole there that we can stick the wire through. And so the first thing we need to do is just kind of remove the battery. So we can push the wire through and then just loop the wire up. And as long as the wire's connecting against the side of the holder and the little rivet there, we'll have a good electrical connection. Because that spring that's inside of the battery holder will push the battery against that. And so we'll be able to make sure that we have good solid connection. And once we put our battery back in, we'll test it to make sure everything's working. So I've put just a little bit of tape around the motors to make sure we could see them spin. So you can trigger the motors with a single pull double throw switches or the lever switches, or you can turn them on permanently with a sliding switch. So when you push the single pull lever switches causes the motors to back up and that's going to mean that our spout bot will be able to reverse.