Where to buy 12 volt LED's

I have Nylint 1:6 scale RC Rock Crawler that runs off a 12 volt battery. I want to add some headlights/tailights to this thing so i can run it at night. I need some 12 volt LEDs.

I know you can get a 12 volt LED kit at Autozone that comes with 6 leds but i've seen them before and the light output is pathetic.

Help.

Might be easier to just resistor (or even regulate) the LED rather than find an actual 12V LED.

iNDiGLo said:

I have Nylint 1:6 scale RC Rock Crawler that runs off a 12 volt battery. I want to add some headlights/tailights to this thing so i can run it at night. I need some 12 volt LEDs.

I know you can get a 12 volt LED kit at Autozone that comes with 6 leds but i've seen them before and the light output is pathetic.

Help.

Click to expand...

As another poster points out, it'll be easy to use common LEDs with an appropriate resistor. Not to worry.

But first things first, what diameter of LEDs are you looking for for the headlight and taillights?

Doug Owen

Doug,

I guess the diameter would the the same as what you would see in any keychain light. Like in the Photon keychain or the Inova keychain led.

What i'm wanting to do is mount 8 LEDs in the chassis. Two for the headlights, two for the taillights and the remaining four under the chassis to illuminate the wheel wells.

If i were using the Autozone cheapo 12v LEDs you'd simply mount all the LEDs then run their anode/cathode wires back to the battery. So basically all the LEDs would be in parallel with each other? Its no different than adding extra "offroad" lights to a real vehicle.

But as you suggest, if i could find some really nice/bright lower voltage LED's and resister them i'd certainly be up for it.
Clear as mud, huh?

Next question is, do you want them to all be 'white' or different colors?

All white baby!!!

If you wanted to buy some "12v" leds, you're really buying a 3.5-3.6 volt regular led with a resistor already attached. That's okay if you want to make things simple. You have your two wires to just connect to the power supply in parallel.

But, if you want to make things brighter and more efficient, I'd have three seperate circuits in parallel:

Two of them would run three leds in series each like this---
[12 volts - (3.6 vf each led*3 leds in series)] /.02 (twenty mA each) = 60 ohms

So, do that twice for the first two sets of three leds.

Then for the last one:
[(12 volts - (3.6 vf each led * 2 leds in series)] / .02 (20 mA each) = 240 ohms for that resistor.

If you have a multimeter, you may want to check and make sure that 12 volt battery is really 12 volts. If it's higher, we'll just increase resistor values. This is going to look nice. If you do want to have other color leds (like red taillights), we can make it work out that way too.

ROVER said:

Then for the last one:
[(12 volts - (3.6 vf each led * 2 leds in series)] / .02 (20 mA each) = 240 ohms for that resistor.

If you have a multimeter, you may want to check and make sure that 12 volt battery is really 12 volts. If it's higher, we'll just increase resistor values. This is going to look nice. If you do want to have other color leds (like red taillights), we can make it work out that way too.

Click to expand...

I'd suggest you do them in four pairs. The battery voltage varies a lot in these rascals, you'll need more voltage across the resistor to get reasonable stability.

I'd suggest some of the hottest 5 mm parts you can get for the headlights, red or amber for the tail lights (maybe 3 mm parts to stay in scale) and for sure 3 mm parts for the hidden ones, they're half the size......

Doug Owen