Help Me Fix a Flashlight, Please...

[Guncrazy]

I've got a little LED flashlight on my keychain. It runs on a single AAA battery, and has an aluminum body.

Recently, it stopped working, so I assumed that the Energizer battery had died. When I replaced the battery, it still wouldn't turn on, so I looked inside the body and saw what looked like some corrosion. I scraped off the contacts, put everything back together, and that seemed to fix the problem.

The next day, though, it refused to light up again. So I scraped out the insides more thoroughly, washed it, dried it, and gave it a light coating of oil. It lit up again, but a few hours later, died again.

Anyone know how I can fix this permanently?

[Aglifter]

Streamlight makes a pretty nice flashlight in that size, which is available from amazon for $12...

[Aglifter]

It's up to $16 now, but it's a great little flashlight.

[Guncrazy]

The flashlight I have is a Fenix E01. Not terribly expensive ($14 at Amazon, but I got it for $6 a couple years ago), and easily replaced, but I do like to fix things myself, if I can. I'm not sure I could give a meaningful description of it's conductivity and switching designs, though. And that Streamlight looks pretty good...think I'll try it out.

[Netpackrat]

I know that I can be a cheap SOB at times, but a thread about fixing a $6 flashlight? Really?

[randy]

I'd look at it not so much as being cheap but as learning how things work and developing skills for the time you might have a failed piece of equipment and don't have the option of buying a new one.

[Greg]

I've got a little LED flashlight on my keychain. It runs on a single AAA battery, and has an aluminum body.

Recently, it stopped working, so I assumed that the Energizer battery had died. When I replaced the battery, it still wouldn't turn on, so I looked inside the body and saw what looked like some corrosion. I scraped off the contacts, put everything back together, and that seemed to fix the problem.

The next day, though, it refused to light up again. So I scraped out the insides more thoroughly, washed it, dried it, and gave it a light coating of oil. It lit up again, but a few hours later, died again.

Anyone know how I can fix this permanently?

Vinegar and q-tips. The neutralization reaction bubbles and makes a little sizzling sound. (So you know when the alkali is gone, you apply vinegar q-tip and it doesn't sizzle.)

Edit: To clarify- I will wager what happened is that your battery leaked. What leaks out is nasty corrosive alkali- to stop the ongoing corrosion you'll need to neutralize that stuff which is what the vinegar is for.

[Termite]

Terralux LS 100 $15, and it will most likely smoke your old light. Sale ends tomorrow.

[Rich Jordan]

Sounds like you've got bad anodizing, allowing galvanic corrosion.

Probably not going to be able to fix it properly, but you can try. The problem is, there are a number of designs for the conductivity and the switching; unless you can tell me pretty accurately what the design is, I can't give you an idea of how to fix.

Honestly, you're probably just better off replacing it with something better.

Fenix E-01 has a solid based tube with removable head. The light is turned on by tightening the head into the body tube, turned off by loosening. The battery negative contacts a spring in the base of the tube, the interior of which appears not to be coated; the internal threads also appear not to be coated. The tube body inner diameter below the threads (where the battery is held) is smaller than the threaded area. There is a flat step between that reduced area and the threads that appears to be the contact area for current flow.

The head has male threads that do appear to be coated, and an o-ring to seal.

The circular circuit board in the head has a center contact for battery positive, and two small gold contact areas at the outer edge of the board that appear to make contact with the 'step' in the body tube. There is no springiness to the contacts or the circuit board.

If I had to guess I'd look at that step in the body for any corrosion, or anyting that would prevent tightening the head all the way in, or if the o-ring is damaged and perhaps prevents the head from tightening all the way.

[Guncrazy]

I know that I can be a cheap SOB at times, but a thread about fixing a $6 flashlight? Really?

Actually, the same thing happened to one of my SureFire lights, and Surefire replaced it. Problem is, there will be times and situations where the warranty or "buy a new one" options are not available or convenient. Like Randy said, if I could learn to fix a problem with corrosion on on aluminum flashlight, that knowledge might be applicable to another.

Vinegar and q-tips. The neutralization reaction bubbles and makes a little sizzling sound. (So you know when the alkali is gone, you apply vinegar q-tip and it doesn't sizzle.)

Thanks, I'll try this.