How to care for a flashlight

How to care for a flashlight

Your flashlight is potentially one of the most important pieces of kit you can have.
This is the instrument to help find the tripped switches, a purse, or that lead in the engine that has come loose. Or maybe you don’t mind your truck being broken down by the highway, leaving you stranded in the pouring rain as that tornado howls unnervingly ever closer up the valley?

But, even wrapped in seemingly bulletproof rubber or aircraft-grade aluminum, they are susceptible to corrosion and wear and tear. So it stands to reason that, even if you’re only using your flashlight irregularly, when it’s called for, it’s absolutely vital that it works.

There are several things that can be done to ensure your light is perfect for every emergency bar the zombie apocalypse (you don’t want to attract the undead by showing light).

A few minutes every few months can save you the expense of a new flashlight and give you peace of mind that it’ll shine brightly when you need it most.



Even if it’s just left in the toolkit under the stairs, as opposed to being taken out most nights on a run, every now and again the light is going to need cleaned. It’s the most basic thing that can be done. A simple cloth, a microfiber fabric or an alcohol pad or wipes should be all that’s needed to have it close-to-shop condition.

Dried-in stains from having been dropped in mud can be tackled on the body of the light with an old toothbrush, but don’t put too much force into it, or you could potentially scratch the surface. Use a light brushing motion to get the loose dirt off, and then go in with the wipes.


The lens, as you may imagine, is the most delicate part of the exterior. It’s important not to push around any rough dirt or grit. Depending on how waterproof your flashlight is, you can thoroughly wet it to loosen the dirt, then carefully wipe it with a terry cloth. If you wear eyeglasses, a little squirt of eyeglass lens cleaner can also work wonders.

Battery compartment

Care for a flashlight: Corroded battery
Don’t let your batteries get into this state

Open up the flashlight and take the batteries out. If there’s any kind of seepage or leakage from the batteries, throw them away. Don’t just wipe them off and put them back in the battery.

If there has been a battery leak, you need to clean away any goo, being careful not to let it get on your skin as it can be an irritant.

Clean the inside of the compartment thoroughly. If you’ve got any corrosion, using a product like DeoxIT will get rid of it and have your contacts in tip-top condition again.

Replace the batteries, or put in new ones. Wipe any grit from the screw threads (if applicable) and put the battery compartment back together again.


Check the O-rings, if your flashlight has them. They are a vital barrier preventing water and dirt getting in past moving pieces of your flashlight. If they’re broken or missing, replace them immediately.

Many manufacturers supply spare O-rings. If not, you can usually pick up suitable replacements at a hardware store.


It’s best to do this annually at least, but check regularly. Various parts need to be lubricated, but with not a massive amount of lubricant. A small squirt of something like WD40 is usually enough.

Underwater use may require a slight thicker layer of lubricant. A silicone-based lube would be better in this case, as it is less prone to the water washing it away.

Once you’re done, put the parts back together and screw into place. A few minutes’ work should have the flashlight as good as new.