very messy xpg2-mod, or: We don't make mistakes....

...we just have happy accidents.

(I dedicate this mod to the late Bob Ross, who after all these years still thrives on Amsterdam local tv . "this is your bravery test" )

I had one xpg2 3D tint on 16mm board left and decided that my only 18650 XML-thrower had to be sacrified (I am not much of a thrower person, but there is one camping trip in spring I can't appear without a new impressive light, ) It is the famous 'Designer's A10-1' (the names are getting better over time at dx), that I recently had enriched with a NANJG 2.8A driver. Head diameter is 5.7cm, I had measured throw (after 1 minute on high at 1m, with uncalibrated meter) at 40Klux, but what would that light do with the xpg2? So it had to go . This is how an easy mod became one full of surprises:

1) Here it is, still in working order, soon to be victimised

2) large smooth reflector, it is a good thrower!

3) internals spread out. (top right: hey, does that light come with this driver?? )

4) the original led is on a 20mm star, the new one is 16mm, but I think I can get away with that. 2.8A is rather much for the xpg2, so this nice new 2A current controlled driver is going in as well!

5) this driver needs a spring

6) ah, there it is.

7) new driver and led soldered in. I screw the pil in for a quick test: yes! the led lights up nicely, and the three modes work too

Dear reader, I am afraid this is the end of the smooth and tidy part of this mod. People who only like pictures of a clean job properly done better stop reading right now!

Ok then, still there I see. I added some arctic silver, screwed the pill in, placed the led containment ring and tried to position the reflector in place. Nothing fitted, the ring was xml size, so the hole was too wide, the reflector wobbled about and could not be gotten close enough to the led because it touched the solder blobs of the wires, so I hammered the solder flat, then some short occurred, I cut some solder away with a knife, Led worked again but the reflector still wasn't close enough, so I screwed it too tight against the led-board, it shorted again, resoldered the wires, still short, new cuts with the knife to clear solder away, etc.etc.etc. The end of this long story: I totally #*%# the led board (8,9), led stopped working and still the reflector still was not close enough to the led.

At this point I decided that it was never going to work with the 16mm board, I needed the led on a 20mm star, I almost gave up. But suddenly I remembered reading about the Old Lumens reflowing technique (thanks for that O.L.). No experience at all, but I could try to remove the led and put it on the 20mm-star. So I heated up the xpg2-board with my 15W solder iron and tried to remove the led with a forceps, not surprisingly the iron was not nearly powerfull enough to meld the solder. Got frustated and tried again with a gas lighter under the board, the led still wouldn't get off. And then the forceps slipped away and chipped the dome off the led, *ouch*, end of project!

10, 11, 12) But is it? Hey!, that doesn't look too bad, some phosfor chips are spreaded out, but the dome looks phosfor-free, who knows, can that led still work? I have a go, scrape and clean the led-board as good as it goes and re-solder the wires. And the led lights up!, I have a working dedomed xpg2!! Makes me wonder if the new line of Cree leds can be dedomed more easy than the old ones .

13) here's the dedomed disaster in close-up, bits of silicone everywhere, but the die is clean:

Can't use this led anymore for the (former ) xml-thrower, so what next? Hmm, my Romisen RC-G2 has gotten a driver update this spring (SKU: 25505 from dx, I was lucky: it draws 2A from a 14500 and the XRE still rocks!). I like the light as it is but with the 2A it delivers, it is tempting to put this new dedomed led in that .

I'l do it:

13) here's the good ol' Romisen

14) got the trusty XRE out (I will keep it for some future use, this is one with the small die and it has proven to handle large amps). Cleaned the pill from thermal glue.

15) some arctic silver added

16) there it is in place

The pill is a bit wobbly when in place, difficult to center under the reflector now the XRE-ring is missing, so I put a tiny rubber band around the upper side of the pill so that it centers itself when fully screwed in the body.

17) Ready. Well not definite, I haven't attached the led-board to the pill with anything else than arctic silver, so at some point I have to drill some holes and screw the led onto the pill. But for now it will do.

I hope it works and that the Romisen performs at least a bit better than with the XRE. And it does! Some observations and measurements:

-tailcapdraw with freshly charged TF flames 14500: 2.2A (!, because of the lower Vf?), not so freshly charged anymore: 1.7A

-lux after 1 minute at 1 meter: 15 Klux. (I am sorry, forgot to measure the lux before the mod, with the XRE at 2amps, it was already a hell of a small thrower, and it is now at least as good -maybe better-, but with more total output)

-white wall hunt: see pictures (phone camera, so no settings; on the left on automatic exposure and white balance on tl-light, on the right same beam but amplification on '-2 eV' to see the contrast in the spot better)

-the tint has changed by dedoming, tint 3D is supposed to be just under 5000K, dedomed it has shifted to around 4000K, actually quite near the tint of the xml T4 4000K I have in another mod, still far from ww, but a friendly color . I love this tint, especially for outside!!!

Finally some outdoor-shots. Sorry guys, I have no thrower left for comparison, just some rainy pics in the park (top left=control shot, error:tint is not 3C but 3D). My phone camera makes it a bit brighter and greener than in reality, but I must say this light is a really nice little thrower (usefull light to I would say 60 meters) with (for me) great tint. I hope it will prove to be robust as well.

So this is the end of a simple swap going wild. I had fun doing it and writing it down for you (though it costed me a few late night sessions). Hope you enjoyed reading!


Keep em’ coming! 8)

Thanks for sharing! Sounds like some of my efforts! The key is not giving up.


Now make an insulator and hold the big reflector up to it. :bigsmile:

Very nice recovery! It has me thinking of all the abused romisens sitting unloved in a box. May have to give it a go. Nice mod, and thanks for sharing your efforts :)

Way to go. I could not write that script if you paid me. Whats on the agenda next?

Great job!

After this, I definitely would throw it to trash and think that the project is fully failed…
But you will not give up! And the result is really good!

this torch. He’s like a lumen sniffin’ hound dog. Once he’s on the scent forget about it. He’s getting the sucker to fire up come hell or swamp water. :bigsmile:

I never imagined that way things went either. Usually when I screw things up, that's it, end of story, money down the drain (happens quite a lot actually )

On the agenda now is work and family, but,... I did order a new xpg2(2b this time) on a 20mm star to have another go at the big reflector thrower, should go straightforward this time. I have a copper maratac that screams for the new xpe2 (waiting..., not available in neutral and on 10mm board yet), and I want to make a 18650 powered adjustable desk-lamp with three Nichia219's (that may be a nice project to report here sometime).

Please keep the stories coming. Even if it all works as planned, lie and make a story up for us. We all need a good laugh. Thanks.

Good stuff, thanks for sharing!

Shame you couldn't get it working in the thrower. I was really looking forward to see the results you got from it. Would have been the first real thrower modded with an XP-G2 AFAIK.


was highly enjoyable reading, thanks for it!!

hmm.. why dont you link the posted images to the full-size images, i.e.

[ url=hxxp:// ][ img ]hxxp://[/img][/url]

I linked the images to the maximum size on, which is the size in which I uploaded them. I did edit and resize the pictures on my computer before uploading, because many images were -in my opinion- unneccesary large for what can be seen in them.

I can read the post with the image size I was intending them to be both at home and work, but perhaps something goes different on other computers or browsers (I use firefox)? Any thoughts?

Actually it has worked for a moment, with the led just a bit too deep under the reflector. Did a quick (not to annoy the neighborhood too much ) test outside from the balcony and I can say that the throw was promising!

Beamshots or it didn’t happen! :bigsmile:

Well, nice that you have the new star on order, anyway.

it’s a shame it didn’t work out quite like you’d hoped, but it came good in the end! I have a couple of those RC-G2s and they’re lovely little lights. I’ve been meaning to try a couple of different emitters (XP-G R5 and Nichia 219) in them to see what happens, this has given me extra inspiration!

if you want to reflow in future, just use the electric hob on your cooker or a skillet. Takes seconds and it’s a lot easier than it sounds.

The thing I do not like about the stock RC-G2 is that it has enough heatsink for a 1amp+ led, but can not take 14500's, and a driver swab is not straightforward because it is 15mm and there are no nice 15mm drivers for sale, so you have to file down a 17mm one. But once you have gone through the pain of fitting one in it is a great host.

Thanks for the advice, have quite a few spare leds on boards lying about (mainly cool white xml's and XRE's ), so I might do some reflowpractice in the near future

true about the 14500, but I’m pretty happy just using AAs as they’re back up/ glovebox lights for me. I’ve looked into multimode drivers for AA but there’s nothing particularly appealing out there.

There are a bunch of videos around on reflowing and all sorts of different techniques, but they all follow the same principle.

Great story. I first saw this thread at work and could not see photos at work. By the time I got home, I didn't remember it any more.

Definitely, I see a 40 watt soldering iron in your future, with a small tip. Looks like that's most of the problem.

It all takes time and practice.

Keep up with the mods, it's a lot of fun reading your story.

I just ordered a 40W iron, I can't believe there is one with good reviews for 6 dollars (at dx)! Hope it will direct enough heat to the tip for this purpose

I wil keep on modding, and keep enjoying your and the other's stories as well