About this video
The builder cleans the motor leads and solders new 18 gauge solid copper wire onto the motor contacts. Good solder joints wrap fully around the copper, and the wires are secured with zip ties through the chassis holes. Plastic nibs are filed so the motor sits flat and the zip tie holds it firmly.
You'll be able to
- describe what makes a good solder joint on a wire
- explain why a wire's thickness matters for carrying current
- explain why parts must sit flat so a fastener grips them
Key words
- Solder joint
- A metal connection made by melting solder so it flows around and bonds to the wire.
- Rosin core solder
- Solder with a flux core that helps it stick to the metal.
- Gauge
- A measure of wire thickness, where smaller numbers mean thicker wire.
- Solid copper wire
- A single metal core wire that can carry more current than thin stranded wire.
- Shim
- A thin piece of material placed under a part to level it.
Transcript
OK, so we got our motors clean. The wires are removed and they're ready to be soldered with new wires. We selected 18 gauge wire-- I think that's probably enough for what we're doing. And we're going to determine how much wire we need by feeding it through our holes here and then-- the wire's going to need to run to our motor controller here.
So the motor controller is going to be in this location, and we'll probably mount it like that. So on this side, the wire doesn't need to be very long at all. On this side it's going to need to be longer. So that'll be one length that we're going to need, and it's a little bit longer than the wires that we had before.
But these wires are smaller, and they'll be easier for us to route. And they're solid copper, so they can conduct a fair amount of current if they need to-- certainly rated for what we're going to be doing. I'm going to bend the wire around like this, and that way I can hook it around the contact for the motor.
So I'm using 60/40 rosin core solder. I like the rosin core because it tends to stick better. There we go. Just want to make sure that the solder is completely surrounding the copper. And a good way to do that is to just heat the copper, and the solder will flow over it.
There we go. Oops, that one moved just a little bit. That's OK. So you can see that there's a complete contact with the hairdryer motor. Closest to the motor, pull the zip tie around and feed it back through the hole on the other side. These zip ties are actually way longer than they need to be.
I kind of prefer long zip ties, because it means that you can use them on more things. But you can use much shorter ones, and they are cheaper. Remember, we cut those little flanges out of the bottom of those. All right, there we go. I want to make sure that's lined up well.
This little one doesn't want to quite work into the place that we want it to go, so we'll take the zip tie and try and pry it over. Sometimes these things can be tricky. Let's see if we can get this. We may need to loosen it just a little bit. One thing I think we might want to do is, just to make sure that the zip tie has good contact with the motor, it might be OK like that.
I think it might be OK like that. We'll give it a shot. We may need to file down these two pieces right here later. And it's pretty tough stuff, so it's kind of hard to snap off, but there we go. Got it. So this will be our shim. Hopefully it's not too big. Looks like it might be, actually.
I think it'll be all right. So those are in, let's double-check the wheel turns freely. And it's in there pretty good. Looks pretty decent and seems like it can support a little bit of load, so we'll go ahead and trim off these guys. And now that it's in there, may try and just give it a little bit more.
So now we do the other side-- this guy here. Woo! OK, so we have our motors in place.
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