Cree XR-E'd Ultrafire 602A

Don't have a camera, as many of you know. Hopefully I can get one cheap on ebay sometime, don't care about megapixels, just as long as it works and is cheap!

But here is the details anyways. I tried to make it short and simple.

Ultrafire 602a (Fenix L1P clone). Cree XR-E P4 WH. IMS 17mm.

The top PCB where the luxeon/clone led leads are soldered to is epoxied down and didn't pop off. There is epoxy below this ring, and I didn't dremel down to see where it ends.

I dremed the heatsink ledges and into the pcb to accomdate the cree. I left a little of the HS lip to help align the cree on the Y axis so all I had to do was center by X. Cliped the postive corners of the cree to isolate the bottom, tinned the top pads first, then AA'ed it down. Then I soldered some more wires to lengthen the stock ones to the cree.

Next was to drill the reflector so the metal ring of the cree goes inside. Then grind the back side down and keep checking for focus. Once you are happy with the beam, don't go farther. I used a spare cree mounted on a pentium heatsink to check the focus, which will be used in another light (more on that in a few days) :naughty:. Next you gotta sand/grind a bit around the top of outside of the reflector to reduce it's top most outer dimension. Not much just helps it go into the light better. Then you gotta grind
down on the outside bottom to clear the wires going to the cree solder pads so the led will go far enough into the reflector. The first "notch" for the wire I did fine, but then when I did the other wire, I knew how much I had/could take off and ground it at once and ended up getting the reflector too hot and some of the coating got a little spot where it overheated. Cleaned and re-assembled everything.

Now since the convertor sits up higher in the head, it wont make contact with the body tube. Grinding the head backside won't help, as the threads will bind on the battery tube after it gets to the area for the o-ring. Only solution other than removing some threads in the head is to lengthen the contact area of the body tube/converter-heatsink. I found 2 copper washers laying around, I have no idea what they go to, probably something car-related as that's another hobby of mine. They were just the right size with a large hole in the center. Put two in, and they rattle. Need more. So I took a peice of ~18gauge stranded copper wire and stripped it. That worked, so I soldered the wire in a ring between the two washers and filled the whole thing in with solder nice and solid. Re-cleaned it again with sandpaper and acetone, and dropped it in. Now we need the postive contact to come up. Solder isn't enough, so I found a spring and cut it in half, bent a nice little point for the battery, and soldered it to the center of the circuit board contact. Problem solved.

How bright is it? Well it's probably more than when I had the SX0H luxeon1 in there, which was really, really bright itself. Defiantly a lot more light, probably lumens in the high 40's out the window. And the window is glass on these lights not plastic. I already knew that by looking at them (flat and not scratched). When compared to a 123a ultrafire on li-ion and both are warmed up, the XRE mod beats it. When cold, the li-ion light is a little brighter.

Took me 3-4 hours to do this mod start to finish. With eating a meal included. Sure did suprise me with the extra work I had to do.

--

This will become a new EDC for me, along side with my ArcAAA. ~2hours of bright light from a single AA NiMh cell.

The WH tint is warm, and not really noticed unless you fire up another light next to it, or you are concerned with your white walls/papers looking really white. But remember this Cree is underdriven and not even at 350ma spec, so with that in mind the tint is not that bad!! It reminds me of a hotwire pushed at it's max whitness. If you are put off by white leds and their cold/blueness the WH tint will do you well. It is a nice warm-white tint and not pukey at all. Natural looking I'd say. However if you drive it at 350ma or even 700ma or beyond it should whiten up nicely. Reds look great with this tint.

I spent 5hrs non stop shoveling snow and ice today, and maybe got a little over 1/3 done. I'm not going anywhere for a while So I'll probably just keep modding away....

nice work. thanks for the writeup

the cree is really changing everything!

good work sir!!!

send me the light and I'll take pics :devil:

:lolsign:

Atleast we know there's no Kumar in ya Green man!!!

greenLED said:

send me the light and I'll take pics :devil:

Click to expand...

:laughing:

Well, I have a couple of L1P clones that I've been wanting to do something like this, but just haven't had the time.

good work!

From your write up, the entire modding sounds soo complicated, but glad it turn out rather well.
This thread is useless without pic. So get some pic or send the light to me (AND NOT to green ). I will gladly take some picture for you

You did not mention what the beam looks like. Can you give a quick description and comparison with the original beam from SXOH?

The original Ultrafire reflector gave a wider beam than the stock Fenix. It had the spot with a slight corona around that.

With the XRE and the IMS 17mm, the hotspot is a little bigger than the Fenix beam. I'm sure this varies if you raise/lower the cree as I don't know how much I took off. The beam is no where near as smooth as the luxeon beam (more on that later) but not as bad as a maglite incandescent beam.. The dark "ring" everyone talks about isnt' that bad. It's actually more of an optical illusion that it's dark there. There is a slight less intensity, but its really small. The reason you see that is there is a sharp tight bright ring around that area that fools you.

Going from center outwards: Hotspot, with some swirly marks like you'd get from a colored (blue/green/cyan) luxeon3 in a C/D mag reflector. Spill, then a bright thin ring, then the rest of the spill. The spill between the bright ring and the hotspot is like 90% the brightness of the main spill. Not really a dark ring IMO.

Reason why the hotspot is ringy like a green/blue luxeon is because how the phosphor is applied to the cree. It's sprayed on very thinly (like spray paint), you can see the raised portions of the grill on the die. The luxeons have a much thicker coating of phosphor over the die, which results in the top of the phosphor being flat, so you get a smooth beam. The luxeon looks like a thick pre-shaped square wafer of phosphor is stamped on the die... So that is one reason why the hotspot isn't as pretty, but the thin phosphor may be why it produces more light?? Or at least it's a different application that doesn't infringe on others patents....

I may or may not have the reflector in optimal focus. I didn't want to go too far. It might tighten up more and be prettier with it deeper in the reflector.

no, you dont want to get tighter beam. The tighter the central hotspot is, the smaller it is, and thus, the more pronounced the "dark ring" will be. But it is a trade off really. the choice comes down to whether you want tight beam in the center and sacrifice the prettiness on the white wall, or you rather have less tight beam in the center with less pronounced "dark ring" effect.

I speak from my experience putting a cree inside a PR-T head. Maybe since this is a different reflector, the result would be different.

I see. I figured it might get worse if the reflector was tweaked more. I don't feel like messing with it or I might try to get a better spot.

The bring ring I believe is from the dome lens that has a little bump/ridge around the side of it. I'm sure some have seen this. I bet the reflector picks this up and the ridge acts as a mini-magnifier to intense the light and make a ring around the side light.

here is a pic of my pt eos modded with a cree in a sanded down ims17 vs a HDS b42 on high. Likely very similar to your mod.





the eos had a rxoh in it before, which wasnt nearly as bright as the b42. it hangs pretty well now. now i'm curious about how the runtime is affected.

My bright ring around the hotspot isn't as close to the hotspot as the one in your pic. Perhaps I can make it tighter still? hmm

I'm collecting some FU lights for mods... see my signature

I look forward to receiving some CREE XR-E's on a new buy.

Using this light it seems brighter. Don't know what's up with that, maybe because I'm using it more at night now! lol

The tint is really white when it's got a fresh battery in there. When it's about done, is when you can kind of notice the warmness. The other mods with this bin will be driven at spec/over so I can't wait. I need to do a runtime test (eyeballed again) and see how it compares to with the SX0H mod I had in before this... I know the brightness is great for a single AA! I've almost forgot that it can be driven harder and more lumens can be had from this little LED!

EngrPaul: look forward to your mods!

I finally got around to mod my UltraFire WF602-A with a Cree XR-E as well. I did take some pix.

My procedure is similar to IsaacHayes' only I didn't dremel into the converterboard, just put the XR-E on top (Isaac's method probably is better for heat transfer) and I modded the stock reflector.

First I clipped the corners of the positive contacts from the cree with pliers to prevent shorting:



Soldered it to the converter with some cooling paste inbetween:



At this stage I screwed the light back together (knowing the beam would be no good) and found out I couldn't screw it back all the way... there was a 1 mm gap left. beamshot was better then I expected (see pic below). Next I drilled out the hole in the reflector to 8mm. And I sanded almost 1 mm of the reflector end but the the led contacts shorted against the reflector so I had to use my dremel to remove about 0.5mm of the inside as well. The beam is not 100% perfect yet, I need to remove just a little more I think (but tired of sanding right now)


Here a beamshot BEFORE modding the reflector (on the left) and AFTER modding the reflector on the right.



The tiny dark spot on the right beamshot is only visible when shining on a wall from close distance (less then 1 meter), from further away it appears as if there's small artifacts in the hotspot (they don't show up on my pics)

Hope you guys find it inspiring and show more mods

edit: added the 'after modding' beamshot

Knoefz, yeah I ground out the sides of the ring of the heatsink so the cree would sit flush on the solid metal. So yours just makes contact on the outer rim of the centering ring?

From the looks of your beamshot I don't see many artifacts. If the modded one I do next is good, I might go back and mod the other one too.

I'm going to mod the stock reflector on the next one I do (li-ion this time). It's a bit newer design but same model. It has a textured switch cap. Is that like your version? I noticed the newer one has a larger reflector.

Did you have to modify anything due to the shorter reflector moving the LE up further? Or did it still make contact with the body with the stock reflector?

IsaacHayes said:

Knoefz, yeah I ground out the sides of the ring of the heatsink so the cree would sit flush on the solid metal. So yours just makes contact on the outer rim of the centering ring?

Click to expand...

Yep, and the rest is connected through some cooling paste. I'm hoping it's thin enough to still have heat conducting effects. Although the light doesn't seem to get very warm with the cree.

I'm going to mod the stock reflector on the next one I do (li-ion this time). It's a bit newer design but same model. It has a textured switch cap. Is that like your version? I noticed the newer one has a larger reflector.

Click to expand...

I have an old model, with the smooth tailcap. I hope you're able to check the difference in the electronics because it would be nice to be able to run this light Li-Ions.

Did you have to modify anything due to the shorter reflector moving the LE up further? Or did it still make contact with the body with the stock reflector?

Click to expand...

No contact problems occurred. Before I sanded the reflector the head wouldn't screw on fully... There was about 0.8-1.0 mm of space between the head and the body.

Btw, I still can't use Nmh batteries after changing to the XR-E.

It doesn't get warm? Then you need to re-do it and make it sit flush on the solid metal. That ring obviously can't pull the heat away. You need the bottom of the pad to touch the center of the flat heatsink. Mine gets hot very very fast using 1 NiMH. I have another model where I used an amber luxeon3 and it didn't fit well in the heatsink centering thing, and it didn't get hot, so I had to re-do it as it had too much space between the heatsink, and thermal paste is terrible at conducting heat (you want metal to metal, and only use the paste/epoxy to fill the microscopic holes in the metal). I used AA epoxy for the cree mod, since it didn't have anything to center and hold it.

The one I have with a smooth Im only going to use NiMH/Alk in as I don't want to break it with trying li-ion. The one I have with a textured cap the circuit is already fried (it just died from alkalines somehow, I bought it dead from another user.). This one I will DD the cree using li-ion and a resistor. This one will get max current to the XRE vs runing it through a light with a circuit which will burn up power in the circuit and create more heat. I have 1 XRE set aside that has a high vF out of my other 8 that will be perfect for this.

You cant use NiMH at all?? Even ones hot and fresh off the charger (~1.35 volts)? Mine is the old model with smooth cap and it works fine, before with the stock clone led, it wouldn't fire up at 1.2-1.1v, but thats when the battery is dead anyways (nimh). Now is the same, it pretty much won't turn back on if the NiMH is 1.1v, but the battery is totally empty at that point anyways. But alkaline at 1.1v will turn on but being very dim....

Hi,

I was wondering, what is the output voltage and current of the converter?

I re-did my mod, flattened the pil to have better heatsinking. I also noticed it works on NiMh cells fine now. I guess I got a used one last time by accident (my desk can get a bit messy sometimes).

Also removed just a bit more from inside the reflector the get rid of the artifacts in my beam. Unfortunately I messed up the inside of the reflector doing so. I didn't realise it has a very delicate reflective coating on the aluminum. I messed that up by stuffing my polishing dremel bit in there for cleaning purposes... it was a bit yellowish after I did that. So I had to polish the hell out of it to get it shiny again. It's probably not like new but atleast its reflective again. Luckily I don't notice it in the beam though. I hope the aluminum stays shiny but I'm afraid it'll corrode ugly...