How can I keep contacts clean?

[LEDrock]

Some of my cheap lights ( 3AAA lights which uses a battery holder) flicker a lot. I tried to remedy it by wrapping paper around the battery holder to hold it more tightly in place, but that didn't work. Then I cleaned up the contacts and batteries by simply rubbing both ends of each battery, and both ends of the battery holder against the carpeting on my floor. After putting everything back together, I was pleased to see my light work very much more reliably (and brighter). But after just a couple weeks, the flickering starts happening again. But another cleaning fixes the problem, but only for a couple more weeks.

I have no idea what it is that accumulates on the batteries and contacts. There's no leaking going on. The flashlight's batteries and contacts are enclosed inside the tube, so they're not exposed to anything that can dirty them. So what is accumulating on the contacts that keeps needing to be scrubbed off? And is there any way to not allow the accumulation to happen? This problem doesn't happen with my better lights, so I'm thinking there's a protective coating on the contacts of better ones that resist the buildup of whatever it is that prevents a reliable connection between batteries and flashlight.

 

[aznsx]

Yo

Some of my cheap lights ( 3AAA lights which uses a battery holder) flicker a lot. I tried to remedy it by wrapping paper around the battery holder to hold it more tightly in place, but that didn't work. Then I cleaned up the contacts and batteries by simply rubbing both ends of each battery, and both ends of the battery holder against the carpeting on my floor. After putting everything back together, I was pleased to see my light work very much more reliably (and brighter). But after just a couple weeks, the flickering starts happening again. But another cleaning fixes the problem, but only for a couple more weeks.

I have no idea what it is that accumulates on the batteries and contacts. There's no leaking going on. The flashlight's batteries and contacts are enclosed inside the tube, so they're not exposed to anything that can dirty them. So what is accumulating on the contacts that keeps needing to be scrubbed off? And is there any way to not allow the accumulation to happen? This problem doesn't happen with my better lights, so I'm thinking there's a protective coating on the contacts of better ones that resist the buildup of whatever it is that prevents a reliable connection between batteries and flashlight.

Your thinking sounds correct, and you're almost certainly dealing with contact 'oxidation', which occurs to greater or lesser degree depending on quality of the contacts / plating, and the environment (especially humidity / moisture content).

I use Deoxit D100, and have found it to be very good for the cleaning and ongoing inhibition of oxidation on electrical contacts / connections (particularly, but not limited to DC connections). It's not particularly inexpensive, but very little of it is usually required, so it's a good deal.

 

[LEDrock]

Yo


Your thinking sounds correct, and you're almost certainly dealing with contact 'oxidation', which occurs to greater or lesser degree depending on quality of the contacts / plating, and the environment (especially humidity / moisture content).

I use Deoxit D100, and have found it to be very good for the cleaning and ongoing inhibition of oxidation on electrical contacts / connections (particularly, but not limited to DC connections). It's not particularly inexpensive, but very little of it is usually required, so it's a good deal.

At $31 for a 2oz. bottle, you're right about it not being inexpensive.
Is there anything more "common" that can be found around the house that would work? Vinegar, alcohol, peroxide, paint thinner, etc.?

 

[PhotonWrangler]

I've used this contact cleaner with excellent results on electrical contacts. It's a little hard to find but less expensive per ounce than Deoxit. Use in a very well ventilated area.

 

[aznsx]

At $31 for a 2oz. bottle, you're right about it not being inexpensive.
Is there anything more "common" that can be found around the house that would work? Vinegar, alcohol, peroxide, paint thinner, etc.?

Nothing I can really recommend that isn't just a very temporary solution. If I knew of anything far less expensive than Deoxit that would do the job to my satisfaction, I'd probably be using it. There may be other products that can do the job properly that cost less, but I'm not up to date of what those products are right off hand. A 2 oz bottle of D100 (which is what I bought), used as I use it, would probably last me several lifetimes. That was overkill. You can go with a smaller amount in different forms and get out for under $10. Something like these offerings makes more sense. Not to recommend this source, but just for a couple of examples:

https://www.amazon.com/dp/B0015A5AAY/?tag=cpf0b6-20

Amazon.com: Caig Labs D100L-16BX DeoxIT D-Series D100L Mini-Brush Applicator : Automotive

Buy Caig Labs D100L-16BX DeoxIT D-Series D100L Mini-Brush Applicator: Electrical Cleaners - Amazon.com ✓ FREE DELIVERY possible on eligible purchases

www.amazon.com

 

[8th]

I've found rubbing an ordinary pencil eraser on contacts will give you some temporary relief, I guess depending on your use of the light. Doesn't work as well as Deoxit but it works.

 

[LEDphile]

Dielectric grease (available at automotive stores) on the terminals can help protect from oxidation, but will need to be reapplied when you change batteries.