Observation on Ultrafire WF-500

My WF-500 came in the mail yesterday (actually a Trustfire TR-500 but it is probably the exact same light).

This light is made of powdered aluminum like most of the Chinese lights of its ilk, and powdercoated. For those who don't have one, the main parts are the head, primary battery tube, extension battery tube and cap. The negative electrical path is via flats cut into the tube faces. The flats butt against each other when the barrel parts are threaded together. With the extension tube in place the light fits two 18650s; without the extension tube I believe two 18500s.

It looks like the raw aluminum parts are powdercoated, and then the electrical contact flats are hand-sanded to expose the aluminum. When I noticed that the flats were hand-sanded I figured that they aren't making the best electrical contact, because hand-sanded flats generally means they are not exactly parallel to one another, which in turn means that the contact area will be very small.

So, I disassembled the light, chucked each piece in my lathe and trued the contact faces.

Now check this out, before machine work, my light drew 2.60 amps of power. After machine work, it drew 2.62 amps of power on the same cells! A small but measurable gain, probably due to reduction of resistance in the electrical path. BTW, before both tests, all electrical contact areas were cleaned with a generic contact cleaner (nothing fancy like ProGold).

I'm really liking my new $27 light, for the money it offers unbeatable bang for the buck. It's cheap enough and bright enough that I can keep one in each car or wherever I want a bright, cheap, semi-disposable light.

Now let's see how the lamp holds up...

Yours is powdercoated?
My Ultrafire is anodised afaik....

KnOeFz said:

Yours is powdercoated?
My Ultrafire is anodised afaik....

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The various sites that sell them say they're anodized, but this is probably incorrect. For the price, I don't think these lights could reliably be anodized. Powdercoating is way cheaper and easier since it doesn't involve liquids, solvents or any type of chemistry work by the user. Just pour the powder into a hopper, spray-on with compressed air, and bake.

And you think it's also sprayed on the inside of the battery tubes? (mine are black also on the inside). I'm not a specialist on coatings, but I think powdercoating would result in thicker layers of coating (thin layers of powdercoating give an orange peel effect afaik) , not showing as much detail on the knurling and threading.

To be honest 0.02 is less than 1% difference and although it could be due to better contact there are other possible explanations - but totally agree with you - for the price it's a good output!

Has anyone tried this bulb ? It is mentioned with the Lighthound L600 flashlight but it looks as though it will fit the WF-500.
http://www.lighthound.com/index.asp?PageAction=VIEWPROD&ProdID=2950

brunt_sp said:

Has anyone tried this bulb ? It is mentioned with the Lighthound L600 flashlight but it looks as though it will fit the WF-500.

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Interesting. According to this page, the lamp is rated at 420 bulb lumens (~273 torch lumens), but if overdriven to 7.20 volts this rises to approximately 795 bulb lumens/517 torch lumens, which is pretty awesome output, and the efficiency approaches LEDs.

Of course, that's assuming the cells provide 7.2 volts, which at that overdrive level would be about 3.7 amps. Good quality unprotected 18650s could easily handle that.

If your cells are holding 8 volts of output at a fresh charge, that lamp won't last long...

im pretty sure my wf-500 is anodised

brunt_sp said:

Has anyone tried this bulb ? It is mentioned with the Lighthound L600 flashlight but it looks as though it will fit the WF-500.

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No the L600 bulb will no fit the WF-500.

Guys,

Is there a remote switch available for the WF-500 ?

Any chance of DIY options ? Anybody did it ?

Thanks !