I guess, I'm not the only one who believe that lights in costumes and props are awesome. And I guess that a lot of you are afraid of the seeming difficutly or the missing of know how. After trying it by myself I want to show, how easy it is!
The basics: There are a parallel and a serial connection. If you need up to 3 LEDs it would be better to use a serial cconnection, so you can use your power in the best way. If you need more then 3 LEDs you should use the parallel connection. With this you can use more LEDs but you also need more energy.
Take a look the the circuits:
Serial connection: (Sorry for the german words, the pictures are out of my german blog. "Schaltkreiselement" means circuit element)
Parallel connection:
What is important?
The problem is, that LEDs are built just for a special amount of voltage. Too much damange them. If you take a LED which tolerate only 3.5 V and you use a 9 V battery, then you have to kill the 5.5 V which are too much for the LED. So you have to use a fitting resistor, which absorbs the rest of the voltage. And sure you need a different resistor, if you use for example 2 LEDs, because they need more voltage. It's always depends of the amount of the LEDs, their forward voltage and the battery you use. But I don't want to paint you with theorie. I hated thist already in school. We make it very easy:
Resistor calculator
Download this programm and be happy! I always use this to calculate my resistors and it works great! And if you don't like it, google for another. There are a lot of them!
Now, what should you do, if you need more then 3 LEDs? 5 of them would need 17.5 V but a battery have only 9 V. The solution is a parallel connection. Look at my example:
You see, there are two parallel connections and every of them get 9 V, so you can use more LEDs. But like I said, if you use more LEDs, then you need more energy and your battery will be empty faster.
Now we're starting with the practice!
What do you need?
- LEDs
- Resistors
- Switches
- Batteries
- Battery boxes
- Wire
- Solder
- Soldering iron
- Shrinking hose
- Hot air blower
- And tools like cutter, pincers or knife
- Maybe a pinboard too, because to can test your circuits before soldering it
Here is a little picture:
By the way: All of this stuff is very cheap and it's really worth to spent this money for the finish result. Only the tools like a soldering gun can be a bit expensive. But maybe your parents or your friends can help you out!
Now, thing about how many lights and how much money you will need. Enter the date about your LEDs in the resistor calculator and prepare your workspace. Then we can start!
At the beginning you have to isolate the copper wire inside of your wire. I used a carpet cutter and cut a bit in the first 2 centimeter of the wire. Be very careful and don't damage the copper wire. Then draw the rubber off the wire and drill the copper a bit.
Now put a bit of the shrinking hose about both of your isolated wire ends. It's very important, that the isolated wires don't touch each other later so use enough hose to protect them. You'll see, that the LED have a long and a short "leg". The short one needs a negative pole (black wire) and the long one a positive (red wire). (The color of the wire doens't matter, but then it's easy for you to find the right pole.)
Now take your isolated wire, drill it at the leg (take care for the right pole!) and solder it with some brazing solder together.
Then you have to put the shrinking hose about the soldered part and heat it with your hot air blower.
When all of your LEDs are connected you have to test the lenght of your wires. Put your connection on your prop or costume, maybe reduce them and then keep on working.
If you have to connect some wires you can try it like in this picture. Drill their ends togeher, use some brazing solder, shrinking hose and your soldering gun. If you use a parallel connection you have to connects same poles with each other and if you use a serial connection you have to connect different poles together. Just look at my examples.
At the end you have to insert your resistor. It doesn't matter if you put it at the end or at the beginning of your connection. The poles are also not important. You only have to isolate it well (I covered the whole resistor and it's contacts with shrinking hose.)
Then only the switch and the battery box is missing.
I used a cheap 3 pole toggle switch. Here you need one of the left or the right legs one middle one. Connect them well and use enough shrinking hose. When you connect your battery box you also have to take care for the poles, but here you can just look at the right colors. By the way, this long, black thing is my resistor. And then... when everythink is correctly and well soldered...
...It glows!
You see, it's really not so difficult and with a bit of patience there will be no problems. Also you don't need to be a ingeneer. And if you have questions, feel free to ask!
I hope, you like my tutorial and I could help or inspire you a bit!