CE Tech/Commercal Electric 3AAA Mod Possibilities

[JamisonM]

I was in Home Depot today thinking of possibly buying one of their half price led maglites and saw these. I didn't think much of them at first, but when I looked down the reflector I was surprised to see what looked like an XP-E. The back of the package says they even use Cree LEDs. I originally came here with the intention of getting an LED maglite, but I thought I give them a shot. They were just under $10. When I got home I was pleasantly surprised. They have a nice tint and they're real pocket rockets for what I paid for them. They can breakdown completely except for the switch, lens/reflector and pill which are pressed fitted. I think the main thing is to find out how to power them off of something better than 3AAA and how to heatsink the LED better than the empty space under it does.

[pavithra_uk]

3AAA pack can be replaced with AA Li-ion.

this stock heat sink is not enough. it even not seated with star. heat is transfer only through edges of star MCPCB.

Im wondering why they design it as that way since there is no barrier to make its side closed to seat with star MCPCB

if you planing to direct drive, you can lathe solid aluminum heat sink and mount Star. and glue back PCB.

if you need Driver, then make enough space on back of Aluminum heat sink.

[Illum]

no resistor, no heatsink... overdrive protected from AAA voltage sag under load and heatsinking omitted due to internal resistance of the batteries and their inability to power the XPE satisfactorily for long periods of time. I'd say that's the two parts that needs to be improved before considering li-ion potential...

[JamisonM]

I don't think I'll go Li-ion with this. Right now, a single primary CR123 looks to be what I'll use. I thought of several ideas for improving the heatsinking potential of the pill and settled with this. I've seen others use coins before and wondered if it was feasible in my case. I took my dremel out and went to work. I took just enough off the outer edge to make a tight fit. I still have to sand the top smooth, but I'm hoping this will work. Once I'm done sanding, I'll pop it out and apply some Arctic Silver to fill up any small gaps. I'll also sand down the top of the battery tube flat or at least flatter than it is and apply some more Arctic Silver to aid. Using a nickel for part of a heatsink made me ask myself just what's in them. Unless I've read incorrect information, this 1984 nickel is 75% copper and the rest nickel. I'm hoping this will be sufficient for what I'm asking of it.


[EDIT]
I'm still unsure as just to how I'm going to drive this light. I'm trying to keep this as inexpensive as possible. I'm leaning toward a low ohm resistor right now and hoping that the fact a lithium cell is powering it and isn't being drained hard will give me a flatter output.

[mag_guy]

Just picked up a 2 pack. I'll be watching this one

[JamisonM]

Alright, a bit of an update. I've been throwing ideas around on the heatsink and here's what I've come up with. It's still not set in stone. I took apart the switch for kicks. I also sanded the very end of the battery tube a bit. I'm hoping that flattening it out will aid in heat transfer with the pill since the threads aren't the greatest.

[JamisonM]

It's slowly coming together. My order from Digikey came yesterday. After much thinking, I decided to go with a 350mA micropuck. The heatsink is a nickel that's been sanded flat on one side and the edge on the other. I took the spring that's inside the cam shaft of a maglite that was modified and soldered it on the bottom of the PCB. The little metal cup/cap was soldering to the spring just like it would look and fit on the top of a maglite's switch. I plan on making an adapter that will allow me to use AA and CR123A cells as well as sputtering the reflector to help smooth things out since this won't be a thrower.

[Fallingwater]

My opinion is that you're putting way too much effort into such an awful light. I mean, a micropuck? The driver itself costs as much as the whole rest of the light. The $10 for the flashlight plus the $10 for the puck would have bought you a much better flashlight on the usual chinese sites.

There are two things that piece of crap flashlight is good for: 1) harvest the XP-E for a project actually worth of it, and 2) melt-glue in 1 to 5 LEDs and a resistor and drive them from the original 3 AAA carrier. It'd be a great light to drain all leftover energy out of used AAAs finished by regulated lights. In fact, you might want to add a switch to bypass the resistor altogether when the AAAs sag.

[JamisonM]

Fallingwater, from the start, I never looked at these as crap flashlights. Still, it's true, they aren't great lights. I think of them more as lights that have potential. All I've done is allow them to reach some of it. I could do much more, but I've already said I wanted to spend as little on these as possible. For what little I have spent on them; I don't think these little lights are all that bad now. In fact, I think they are decent little lights.

[darkknightlight]

I too bought these lights after seeing them mentioned on another thread with the intent of modding them. I am a complete newbie, and while I have done much perusing of these forums, I do have some questions (and hopefully I am using the correct vocabulary to ask!). Hopefully I am in the right section to ask as well.

I understand that the set-up of this particular flashlight and the internal resistance of Alkaline batteries prevents them from adequately powering the led; would the lower resistance of NIMH AAAs produce a higher output? Would this also necessitate the use of some kind of resistor or a different driver board to prevent the led from being damaged?

I am also wondering about the possibility of powering this light using energizer AAA lithium primaries. I understand that when using lithium power without a proper driver or resistor, thermal runaway and thus venting with flame is a distinct possibility. I see that you installed a micropuck to deal with that when using a CR123a. My question is: between the tailcap switch and battery carrier, is there enough resistance created to safely use AAA lithium primaries?

I had a couple of other questions, but I've forgotten them at the moment. Thanks for any help you can give!

[kkcc]

I only did a very basic mod. Sorry no pictures.

I picked up a pack of these at HomeDepot & went in a different direction for a mod.

I had a 3 D Mag light with the original bulb, still functional but nothing special in ether output or battery life. I pulled the switch assembly & cut down the black bulb holder to just above the switch housing. I soldered leads to the exposed contacts.
On the CE light I removed the star & soldered the leads to the star. Reassembled the switch into the Mag light housing, put in 3 batteries & turned in on. The Cree light up nice & bright for about 1 minute then died. It was too hot to touch.

One star down, but still had one to go. Soldered on the 2^nd cree, & used epoxy to hold an piece cut from an old CPU heat sink. Turned the light on. The heat sink got quite hot, but the Cree stayed lit. I then used the epoxy to fasten the star to the original reflector of the Mag light. ( I first cut the reflector to the base of the cone.

The light is now more of a flood then a thrower.

Two nights later I had to change a tire for my sister, figured this would be a good real world test of my handy work. All told the light was on for at least 45 minutes straight while I emptied all the crap from her trunk just to get to the spare & change the tire. For this it worked great.

PS: I had also brought a back up just because I didn’t have 100% confidence in my modded light. I don’t know what the run time will be, but it should be an improvement.