I have moved into a mobile home in the country. There are not street lights or much light at all in the dark. I want a reliable flashlight to light up the night. I have a few Chinese lights such as SolarForce bodies and XML drop ins and while they are bright….they can not be counted on. They flicker as in a poor connection for example. What can I do with my lights to make sure they are reliable and can be counted on as a solid and bullet proof flashlight? SHould I mess with these lights or buy a light with better quality control such as a Four-Sevens light? I ask because I have a Four-Sevens Preon 2 pen light and that like works every time with no issues……but it is an $80 pen light. Thank you for the help.
Depend on what you need, please check at Mountain Electronic here and Illumn right now have some very good special deal
What batteries are you using? What charger? (specific name and numbers off of them)
Look inside the tailcap, if you see
— gray-black dirt on the threads, wipe that clean with a tissue
Same for threads at the other end of the battery tube.
— 2 little holes in a brass or aluminum ring around the spring, take a pair of tweezers or needlenose pliers, put them in the holes and twist to tighten — often the switch is loose.
Get some “bulb grease” at an auto parts store — “conductive grease” and put a tiny dab on the spring and the threads.
Thank you for the help. That seems to have fixed the flashlight. I wiped out the dirt and old “goo”. I had some dielectric grease in my toolbox and I used a very small amount on all the threads. Put it back together and it seems to be working fine now.
The Yezl Y3 is a very nice light, and would be great for you.
I’m kind of a newbie to this stuff myself but over and over in these forums I kept reading that “everyone should have a Convoy C8” but I could never find out exactly why. So I got one- and now I understand.
For a reliable, all-purpose, high-quality bone-stock light at a great price, you simply can’t beat it. Others do certain things better but none does all of them as good as the C8. It’s now my “grab-it” light in the house; the one I use and rely on most of all. Watch for fakes, get the real thing and you will understand too.
Phil
Right on! Ain’t nothing like the real thing! :bigsmile: Convoy is quality! 
Convoy and ThorFire are kissing cousins when it comes to the C8 or BD series. They are good lights. You could buy a C8 host and build your own, or pay $5.50 labor for build and test on top of the cost for the parts. You can’t go wrong with a custom Mountain built light.
A nice little thrower.
XinTD C8 V5 XP-G2 S4 2B 18650 Flashlight
When you need to make a lot of light.
Supfire M6 3 x XM-L2 4 x 18650 Flashlight
I’ve had great luck with ArmyTek. SolarForce with these dropins http://www.mtnelectronics.com/index.php?route=product/product&path=86&product_id=292
I didn’t know that dirty threads can cause such flickering issue. 
Well that’s the electrical path so yes.
Aluminum conducts electricity, but aluminum oxide is an electrical insulator.
You never see bare aluminum, it makes an oxide film on its surface as soon as it’s exposed to air (and once that layer forms it protects the underlying aluminum from exposure to air — it hangs on tight to the surface rather than flaking off like rust flakes off iron, so in air aluminum doesn’t get eaten away)
Aluminum-on-aluminum threads grind off a bit of the surface and make an electrical connection. But as you exercise the threads that ground-off oxide builds up as grit and keeps the threads from making good contact. But aluminum oxide is abrasive, so if you tighten down it grinds through the oxide layer and gets an electrical connection.
Better to wipe the threads with some conductive lubricant — that also keeps the air off the contact surface, protecting the aluminum that makes electrical contact, so you don’t keep grinding away at it.
Maybe you’ve noticed that if you leave water in an aluminum canteen, you start seeing fuzzy white stuff — that’s the water, keeping the oxygen in the air from renewing the protective oxide layer so the aluminum starts to corrode and continues to do so.
Maybe you’ve noticed that airlines forbid carrying mercury thermometers — same problem but even worse:
https://www.google.com/search?q=aluminum+airframe+mercury
Actually, the Solarforce bodies are very well reviewed, and are quality components. As you’ve found, on a quality light, a good cleaning/tightening makes a big difference. I regularly disassemble the tailcap and completely clean the assembly, and make sure everything is tightened securely when done. This can help a lot as well.
A pair of these is a great tool to have in the flashlight toolbox:
http://www.harborfreight.com/5-3-4-quarter-inch-needle-nose-pliers-40696.html