making led flashlight

Can someone tell me how and what I need to make a led flashlight

You can look on my topic My First LED, a Maglite conversion, or something like that. It tells most of the basic stuff you need to make a replacement bulb. To make just a flashlight, you wont have to worry about fitting the electronics in that annoying little bulb. You are going to need how many volts you need, and how many volts you have. V=IR (I know, but its easier to remember that way). Volts equals current times resistance. If you have an LED that needs 1.8 or some such volts, and 20 mA, you have to do this: 6-1.8=.02 X ohms resistance you have 4.2=.02X X=(4.2/.02) X=210 Ok, this is not going to be exactly right, but it will give you a good estimate. On mine, I used the MAX values to plug in. so, I had 6-2.4=.05X. So, 3.6=.05X X= 3.6/.05 X=72 On mine, I used a 47 ohm resistor. Because I am using extra energy, it is going to be brighter, but also more inefficient. Some of that energy is going to be converted into heat from the resistor and the LED. It is pulling 70 mA, but I dont know how much of that the LED is getting. For your flashlight, you can just tape some batteries together, or buy a cheapie $2 flashlight at walmart or some place and modify that. 2 or 3 cells would be nominal, because you may not have to use a resistor to pull the voltage down, depending on what LED you use. You can use 4 like I did, but then you MUST use a resistor to get less current. I know I left a few things out, but I think I did manage to make less typing needed for the more knowledgable folks here. Remember, take what I say with a grain of salt, I JUST started electronics about 4 days ago when I made my LED. That was the FIRST time I had ever really tried electronics, but, it did manage to work.

Spud
AKA, Chris Coleman

There's so many ways to go!

What do you want? Big or little, white or color LEDs, killer run time or really bright?

Throw in some desired attributes, we'll point ya in the right direction.

As Gadget said, there are many ways to go about doing this.

Please let us know how much you know about electronics so that we can tailor our advice accordingly. Many terms can sometimes be beyond the scope of a beginner.

Also, if you search around the forum with the term "convert" or "conversion", you will find many examples of previous work done to convert a standard flashlight in to a LED light.

here is a nice little project http://www.intelligentchild.com/flashlight/

I built this one because I was to cheap to buy one. I ended up taking most the stuff back since you can buy a good infinity for so cheap or a brinkman led flashlight.