Finished first Saber, everything was great until..

[SirDigbyChknCzr]

...suddenly the blade went super dim. It's been working fine for several days (hella bright), no issues at all. Today I go to play around a bit, bright as normal.. then its like a dead flashlight. Accent LED and Sound are still fine, crystal chamber rotating nicely.. just super dim blade. Plugged it in to recharge, and the charger gave me a green light indicating fully charged.

My DVOM is at work, so I'll grab that tomorrow and bring it home.. but in the mean time, any ideas?

Thanks in advance.

[RavenXp]

Are you sure the LED had the proper resistor?

[jbkuma]

Could be a short or broken joint as well.

[Tom Tilmon]

dead battery?

[SirDigbyChknCzr]

Ok, I'm getting 4ish volts out of the battery to the JST with the LED unplugged. As soon as I plug in the LED, I get 2.3v or so and its super dim. It was fine and bright for several days and now it's barely on at all... what could be robbing the voltage? is the LED bad? I have the .47ohm, .5W resistor coming out of a NB4 into a green single cree.

[jbkuma]

Sounds like you have a short.

[SirDigbyChknCzr]

I just cut back the shrink wrap and it looks like my resistor melted. so.. yay.. probably also fried my LED.

EDIT 1: burnt resistor https://i.imgur.com/VjJOqtT.jpg
EDIT 2: LED is fine, I can give it momentary full battery voltage and its bright AF. Now I just need to figure out why the resistor burnt up.

[SirDigbyChknCzr]

Are you sure the LED had the proper resistor?

I was sure.. but now seeing that its burnt out, I'm much less sure.

[Warlock]

Probably too low a wattage on the resistor. What was it's rating?

[SirDigbyChknCzr]

.47ohm, .5W resistor

[Silver Serpent]

The good news is that your resistor's sacrifice likely saved the life of your LED. Bump up the wattage on your resistor. And maybe don't shrink wrap the resistor itself, just the connections to it. It needs to dissipate some of the heat that builds up.

[SFXER001]

What color LED? Red would destroy that resistor.. but blue or green should have been okay.

[Warlock]

I wouldn't use anything lower than a 2w.

[SirDigbyChknCzr]

What color LED? Red would destroy that resistor.. but blue or green should have been okay.
Green.

[Forgetful Jedi Knight]

That would normally be fine for a single Green Cree. Sounds like you had a bad resistor. The resistor wasn’t heat shrunk, was it?

[SirDigbyChknCzr]

yes it was.

[Forgetful Jedi Knight]

Ok, that is a huge problem. Resistors work by converting energy into heat and the. dissipating it. If it can’t dissipate heat, it WILL FAIL.