[HELP] DIY LED lights for LEGO technic

[VintageCharlie]

Hi folks,

i know there has been much talk about this, but i could not find an idiot*-proof guide on making DIY LED lights that work well with PF elements. The official LEGO LEDs are too expensive for my budget.

I suppose it is not as simple as just buying a bunch of hi-brite 3mm and/or 5mm leds, hooking them up with wires/shrink tubing and connecting them to the battery packs corresponding positive and negative connections.

I'd need 10 lights for a Crawler 9398 set. I would want them just to go on at once as soon as the battery pack is turned on, i might add a switch, but that would be optional. What would i need for this to work properly and not to burn out the LEDs or drain batteries too fast?

* this is certainly the category i belong to in regard to electronics.

[Bzroom]

You should be able to wire all the lights in series and be ok. Maybe wire them in two parallel series blocks. Too much power and the LED will burn out, too little power and they will be dim. There is definitely a formula to use to know how much current each LED will consume and therefor how many you should stack up in a row. If you have few LEDs you will often find resisters to keep the current low enough. Worse case you can put a large resister on the line, if the lights are too dim, try a smaller resister, work your way up to no resister if you need all the juice.

[garethjellis]

This is my fav site for calculating LED s and resistors

http://ledcalculator.net/

[VintageCharlie]

Thanks for the advice guys! The ledcalculator is exactly what i needed.